ABSTRACTS OF THE KEYNOTE SPEAKERS

Ian Burfield

Biodiversity targets 2010: where are we now?

European Science & Data Manager, BirdLife International.

In 2002, world leaders pledged to significantly reduce the rate of biodiversity loss by 2010. To assess whether that target was met, a group of scientists (including BirdLife) used 31 indicators, including those measuring the state of biodiversity, the pressures on biodiversity, and the responses to biodiversity loss. The results were published in Science (Butchart et al. 2010). At European and EU levels, an even tougher target was adopted - to halt biodiversity loss by 2010. This was accompanied by an EU biodiversity action plan. To assess how well that plan was implemented, and whether the target was met, BirdLife's European Partnership made a questionnaire-based assessment at national level. This considered the status and trends of birds and other species, the existence and implementation of biodiversity legislation, the extent and management of protected areas, and the levels of biodiversity research, monitoring, financing, public awareness and governance. I will summarise the results of these assessments, and their conclusions about whether the 2010 targets were met. I will also reflect on how the EU might meet its new target - "halting the loss of biodiversity and the degradation of ecosystem services in the EU by 2020, and restoring them in so far as feasible, while stepping up the EU contribution to averting global biodiversity loss.




Richard D. Gregory

How to estimate the changes in environment: birds as indicators

Head of Species Monitoring & Research, Department of Conservation Science, The Royal Society for the Protection of Birds.

World leaders have set targets to reduce biodiversity loss and their relative success in meeting this aim will be measured against a set of indicators. For indicators to be effective they must meet a range of practical and scientific criteria, driven by the information available. One metric that has proven effective is the wild bird indicator. It is based on the composite population trends of widespread birds in Europe derived from national breeding bird surveys. There are several reasons to believe that birds might be useful bio-indicators. They can be sensitive to anthropogenic factors, are well known, have good time-series, and have a connection with people and their lives. Yet, there are counter arguments and risks in using birds in this way. Interestingly, recent work has emphasized the importance of common species in ecosystem function and suggested that their depletion might significantly affect ecosystem services. The EU and national governments are increasingly using these measures to assess sustainable development strategies and environmental health, as well as in the fulfilment of biodiversity targets. Wild bird indicators only measure a component of biodiversity change and need to be used carefully to assist policy makers and land managers in managing natural resources and conserving nature. In this talk, I will review the strengths and weaknesses of using birds as biodiversity indicators, and look forward to how this work might be developed and extended.




Anthony D. Fox

Eco-energy and urbanisation: messages from birds about wind turbine proliferation

Department of Wildlife Ecology and Biodiversity, National Environmental Research Institute, Aarhus University, Denmark.

By 2010 over 50% of humans live in cities, rising to 70% by 2050. Energy consumption increases exponentially with the proportion of the populace living in conurbations. Currently 85% of global energy consumption comes from fossil fuels, yet many acknowledge the need to switch to renewable forms of energy. By 2035, Finland will consume an extra 14% of electricity compared to now, and would need another 14% again if the country were to switch to electric cars. Such a 28% increase in demand could be met by 2730 x 2.3 MW wind turbines (covering c.1050 km2 of sea). Wind turbines inevitably affect the environment, especially birds, causing displacement from favoured feeding areas, barriers to movement, modifications to habitats and collision mortality. Effective implementation of planning procedures, incorporating Strategic Environmental Assessments at national/regional levels and Environmental Impact Assessment at project level should guide sensitive positioning of wind farm development that can avoid serious conflicts with avian populations. It is essential that we continue to gather experiences from existing wind farm developments and combine these with modelling approaches to ensure that our attempts to save the planet by exploiting renewable wind energy do not come at unacceptable costs to local nature.




Franz Bairlein

Global problems need global solutions

Institut für Vogelforschung (Institute of Avian Research) "Vogelwarte Helgoland", Germany.

Migratory species are of particular challenge for effective conservation because of their reliance on not just intact breeding grounds but at least of similar importance on stopover sites and often far distant winter grounds. Long-distance and trans-Saharan migrants are of particular concern because their population declines during the last few decades are much more severe that those of within-Europe migrants and resident species, respectively. For successful migration most of these long-distance migrants rely on internal energy reserves they have to accumulate before facing inhospitable areas such as sea and deserts with no feeding opportunities. In many species fuelling happens immediately before crossing ecological barriers or shortly after the obstacle to replenish used body reserves and to prepare for the continuation of migration and subsequent breeding. Thus, intact stopover sites are crucial for successful migration and overall fitness, respectively. Climate induced changes on habitats will have impacts on staging, stopover ecology and fuelling in migratory birds, though the effects of these changes are still very speculative due to the lack of detailed studies and the uncertainty in climate models. The talk will emphasize a few of the important issues we have to address for understanding and effective conservation of migratory species in a changing world. These are especially understanding migratory connectivity between breeding, stopover and wintering sites, and un-ravelling carry-over effects between the different annual life-history stages.




Lennart Balk, Per-Âke Hägerroth, Gun Âkerman, Marsha Hanson, Ulla Tjärnlund, Tomas Hansson, Gunnar Thor Hallgrimsson, Yngve Zebür, Dag Broman, Torsten Mörner, Henrik Sundberg

Overview of the paper "Wild birds of declining European species are dying from a thiamine deficiency syndrome".

Department of Applied Environmental Science, Stockholm University, Sweden.

Wild birds of several species are dying in large numbers from a paralytic disease with hitherto unknown cause in the Baltic Sea area. A research team at Stockholm University, Sweden, has demonstrated strong relationships between this disease, breeding failure, and advanced thiamine (vitamin B1) deficiency in eggs, young, and adults. The results are presented in the article "Wild birds of declining European species are dying from a thiamine deficiency syndrome", published in the Proc Natl Acad Sci USA, 2009, 106, 12001-12006.

Thiamine is an essential nutrient for birds and other vertebrates. In the living cell, its phosphorylated form acts as a cofactor for several life sustaining enzymes, which are non-functional if the cofactor is missing. Thiamine is also necessary for the proper functioning of the nerves. Thiamine deficiency was demonstrated in the egg, liver, and brain as reduced thiamine concentrations, and in the liver and brain as reduced activities of the thiamine-dependent enzymes. In the liver and brain, there were also elevated proportions of these enzymes without the thiamine cofactor. Moreover, paralysed individuals were successfully remedied by thiamine treatment. The excess mortality and breeding failure are part of a thiamine deficiency syndrome, which most probably has contributed significantly to declines in many bird populations during the last decades.

The authors stress the urgent need of further investigations focusing on causation. The thiamine deficiency may be induced either by a causative agent(s) acting directly on the affected individual, and/or by insufficient transfer of thiamine between the trophic levels in the food web. Classical persistent organic pollutants are not primarily suspected, since the affected species occupy a wide range of ecological niches and positions in the food web. Last but not least, the authors stress that they are open to the possibility that other wildlife may suffer from thiamine deficiency as well.




Anders P. Møller

Complex interactions between components of global change

Laboratoire d'Ecologie, Systématique et Evolution, Université Paris-Sud, France.

Human impact on the world can be likened to a multi-factorial experimental design with non-random allocation of treatments. For example, climate change, industrialized agriculture and forestry, urbanization and pollution all contribute on their own and in combination to influence our natural world. I provide three examples of the effects of such combinations of global change that highlight the complexity of the environment that animals face: (1) Migration of barn swallows Hirundo rustica to Africa from the European breeding range in relation to environmental conditions in the winter quarters and at the breeding grounds; (2) breeding and abundance of the Arctic tern Sterna paradisaea in relation to climate change and agriculture; and (3) breeding by the goshawk Accipiter gentilis in relation to climate and populations of prey. These examples will emphasize the necessity to study multiple factors when analyzing the consequences of current change in environmental conditions, but also warn against making simplistic analyses and predictions of responses to climate change because many components of the environment change simultaneously.





ABSTRACTS OF OTHER SPEAKERS

Raimo Virkkala, Ari Rajasärkkä

Northern species in jeopardy due to climate change: Population changes of birds in boreal protected areas

Finnish Environment Institute.

The predicted increase in temperature will probably be particularly dramatic in the northern latitudes. Therefore, northern species are especially susceptible to the effects of climate warming and will be in double jeopardy because their projected future range will contract substantially, as the Arctic Ocean will effectively limit their range expansion northwards. Protected areas enhance adaptation of biodiversity to climate change but also provide important opportunities to monitor climate change effects. This is because human land use effects on species populations are minimized in protected areas and population changes can thus be more directly linked with changes in climate. In this study, bird population changes in 96 protected areas in Finland were compared based on quantitative bird census data, between two time slices, 1981-1999 and 2000-2009, with the mean time span being 14 years. Northern bird species had declined and southern species increased during the study period, with a clear rise in mean temperatures. Thus, population changes of northern and southern species are in line with the predictions of range shifts of these species groups under warming climate. The results show that population dynamics of birds are already changing in natural boreal habitats in association with changing climate.




Heini Kujala, Mar Cabeza, Miguel B. Araújo, Wilfried Thuiller

Misleading results from conventional gap analysis - messages from the warming North

Metapopulation Research Group, Department of Biosciences, University of Helsinki.

Gap analyses are frequently used in conservation planning as a "quick-and-easy" method for assessing reserve networks. Using Finnish reserve network and breeding birds, we compared the results of a conventional gap analysis to population trends and to projected, climate change induced distribution shifts. We found contradicting patterns, where the winner species of gap analysis are actually declining, and the losers are becoming more abundant. As the trends correlate with latitude and expected distribution shifts, we suspect climate change to play a role in this discrepancy. We therefore call for caution when using conventional gap analyses in the rapidly warming world.




Juha Tiainen, Jukka Rintala, Tuomas Seimola

Finnish farmland birds thrive better - do agri-environmental schemes play a role?

Finnish Game and Fisheries Research Institute.

As a consequence of changes in agricultural policy, global market demands and climate, Finnish farmland has experienced big structural and intensity changes during the past few decades. These changes resulted in considerable biodiversity losses, including remarkable changes in farmland breeding bird communities. Since Finland joined the EU, noteworthy efforts to balance negative impacts of agricultural changes on nature have been undertaken. The success of national agri-environmental schemes has been studied with a monitoring program, a part of which has been intensive research on birds. Using annual data from about 3 000 - 10 000 ha of farmland in different parts of southern Finland, an indicator based on 40 breeding species was developed. This revealed that except for a couple of species significant declines do not continue. Species with nests outside the reach of farm work showed an increasing composite trend, whereas species breeding on fields or in field margins did not show a significant trend. Species wintering in Europe showed an increasing trend during the past decade whereas species wintering in the tropics did not show a trend. It seems that recent mild winters play a role which may be more significant than the impact of environmental actions taken so far.




Irina Herzon, Johan Ekroos, Jukka Rintala, Juha Tiainen, Tuomas Seimola, Ville Vepsäläinen

The role of set-aside in reversing decline of farmland birds in Finland

University of Helsinki.

The set-aside obligation under the Common Agricultural Policy brought widespread benefits for wild farmland species. Shortly after it was abolished in 2008, the national political process in Finland replaced it with a targeted agri-environment scheme for environmental fallow. Though potentially highly valuable, the value of the current scheme for securing biodiversity is yet to be confirmed. This study evaluates the importance of former set-asides to farmland birds based on the national monitoring data from 2001 to 2006. The set-aside fields supported 20 to 30% more species and held 20 to 50% more pairs of birds typical of open farmland in comparison with cereal fields within a similar landscape setting. Plausible changes in populations expected from a varied conversion rate of set-aside to arable fields are discussed. Based on the current implementation of the environmental fallow scheme derived from the national statistical register, a farmer questionnaire and field survey in 2010, the ability of the new agri-environment scheme to mitigate a plausible decline in birds resulting in the set-aside abolition is evaluated. Finally, improvements are suggested into the scheme so that the Biodiversity target for 2010 and beyond can be achieved.




Ari-Pekka Auvinen, Aleksi Lehikoinen

Finnish breeding bird indicators in a European context

Finnish Environment Institute, Oulu.

As in many other countries, breeding bird indicators form the backbone of national biodiversity monitoring and are used widely in national and international assessments. First habitat specific indicators based on the results of Finnish breeding bird censuses and faunistic data were developed and published at www.biodiversity.fi in 2008. The indicators cover six out of total of nine primary habitat types found in the country: forests, mires, Baltic Sea, farmlands, urban areas and shores. Time series begin mainly in 1979. Further indicators area needed for inland waters and alpine habitats. The indicators mostly follow the methodology and grouping of species used in pan-European indicators. The Finnish common farmland bird indicator reflects the steep Europe-wide decline of species associated with agricultural habitats. The common forest birds - divided into generalist and coniferous forest species - have been slightly increasing, which in contrast with pan-European indicators and begs further investigation. The steep decline of mire birds cannot be represented as clearly and comprehensively based on data from any other European country, and highlights urgent need for conservation action of this habitat. In a European context, the Finnish breeding bird indicators are particularly important in terms of species with a northern or eastern distribution area.




Ilkka Sammalkorpi, Markku Mikkola-Roos, Esa Lammi

Density, biomass and relations of feeding guilds of aquatic birds as indicators of the ecological state of lakes

Finnish Environment Institute.

The numbers of aquatic birds can often be counted while numbers of other taxons, e.g. fish or benthic and pelagic animals or plants can only be achieved by laborious sampling. In science, management, conservation or administration, "ornithology" and "limnology" are in different sectors. Encouraged by studies deliberately overlapping these sectors we reviewed and collected data on water quality, fish and densities of breeding aquatic birds in Finnish lakes and protection sites. We found that trophic status (phosphorus concentration), fish and density of breeding aquatic birds were interconnected. Lakes with a high biomass of waterfowl (dabbling and diving ducks) were also good for species with high conservation value. Many lakes which had lost their conservation value had also experienced a decline in waterfowl biomass, had a fish community dominated by cyprinids and higher density of piscivorous birds. The difference of bird biomass between fishless and cyprinid dominated eutrophic lakes was an order of magnitude. Oligotrophic lakes with a balanced fish community had a higher waterfowl biomass than eutrophic, cyprinid dominated lakes. These findings are discussed from management, conservation and climate change point of view.




Daniel Burgas, Patrik Byholm

Raptors as indicators of biodiversity

University of Helsinki.

The reduction in biodiversity due to habitat loss is intended to slow down by establishing effective networks of nature reserves. Protected areas are often selected through indirect indicators of the protection value. It has been traditionally stated that top predators are very sensitive to different forms of environmental change and thus good indicators. However it is not well understood how well they relate to biodiversity. We use two widely distributed model species - the Northern Goshawk (Accipiter gentilis) and the Ural Owl (Strix uralensis) - to evaluate raptors as indicators of biodiversity and as potential tool to prospect and assess conservation value in boreal forests. The nest location for both species is associated to higher levels of biodiversity at territory level. The spatial coincidence appears for species likely interacting with the raptors (i.e. birds and flying squirrel) and for less interconnected taxa (i.e. polypores and lichens). Our results encourage the use of avian predators as surrogates of biodiversity. Widely monitored raptor species like the ones in this study could be implemented as a cost-efficient tool to refine the nature reserve selection procedures. Simultaneously the study supports the importance of the raptors as sentinels of changes in general biodiversity.




Ville Vepsäläinen, Heini Kujala, Jon Brommer

Range-margin shifts of boreal birds re-visited - the role of temporal variation in mapping effort

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

In recent decades range margins shifts (RMSs) towards poles and higher altitudes have been reported for several species and increasingly these shifts have been suggested to be driven by climate change. By analyzing British and Finnish bird atlas data, Thomas & Lennon (1999) and Brommer (2004) found that the northern range margin of southern birds in both countries had moved, on average, 19 km northwards since the beginning of 1970s. The method used in these studies, however, does not account for mapping effort of atlas cells which is not standardized and thus varies spatially (within atlas) and temporally (between atlases). We developed further the earlier analyses done with Finnish data by exploring the role of mapping effort changes in the observed RMSs. The atlas cells were more efficiently mapped in the second (1986-89) atlas than in the first (1974-79). This change in mapping effort explained significantly the observed average RMS of southern birds (ca. 110 species), which decreased to ca. 13 km northwards and was statistically insignificant (P-value ca. 0.09). Our results indicate that the temporal changes in mapping effort need to be accounted for when analyzing distribution changes based on heterogeneously collected data.




Petri Lampila, Mikko Mönkkönen, Ari Rajasärkkä

Bird communities in old forest fragments are more dense but less diverse than in continuous forest

Department of Biology, University of Oulu.

The Finnish-Russian border offers an excellent opportunity to study the forest fragmentation effects. In Finland, the forestry practices have affected the landscape structure for most of the 20th century. Nowadays, over one third of the old-growth forests are restricted to the nature reserves, which form c. 3.6% of forest land in Kainuu and northernmost Karelia. On the Russian side of the border there is tens of kilometres wide "green belt" of nearly untouched forests (at least at the time of data collection). In this study, we raise the question whether fragmentation effects are involved in structuring bird assemblages in remnant old forest areas in Finland. The data were collected using line transect method from more than 100 forest reserves in Finland and in adjacent areas in Russian Karelia. It turned out that Finnish bird assemblages were not random samples of the continuous forest. Compared with the expected, Finnish reserves had less forest bird species but populations were more dense. We conclude that Finnish reserves lacked some species due to fragmentation effects and that higher population densities are probably explained by higher productive energy than in natural forests.




Patrik Byholm

Effects of natural and human caused habitat heterogeneity in a habitat sensitive forest predator, the Northern Goshawk

Department of Biosciences, University of Helsinki.

Human caused habitat loss continues to constitute the single most acute reason for the ongoing biodiversity loss. While many species respond to habitat loss by a reduction in numbers directly and others are affected indirectly (e.g. though increased predation), some species seem to be able to cope with the habitat alterations by modifying their biology, for example by learning to utilize new food resources and/or inhabiting novel habitat. However, this kind of "forced plasticity" can be expected to be associated with various ecological and evolutionary costs. Examples of such costs include an increase in the utilization of suboptimal habitat and increased turnover-rates of reproducing individuals even though hitherto not being paid much attention in studies of wild animals. Using the Goshawk Accipiter gentilis - a habitat sensitive top-predator of the Holarctic forest ecosystem - as a model species, I will present a set of results from my ongoing research illuminating how natural and human caused habitat heterogeneity influence various aspects of goshawk biology. As these results are likely to hold for other species as well, the current insights can and should be applied also in other contexts, e.g. when planning conservation or wildlife management actions.




Tapio Eeva

Nutrition-related pollution impacts on birds

University of Turku.

Point sources of air pollution are widespread across the world and they sometimes have major impacts on surrounding wildlife. While concentrations of pollutants in biota have been measured at many industrial sites, thorough population level studies on impact mechanisms have been scarce. One such study on wild birds has been performed around the copper smelter complex in Harjavalta, SW Finland. Elevated metal concentrations (e.g. Cu, Ni, Pb and As) occur in soil, vegetation, insects and birds in the surroundings of the factory due to current and historical deposition. Long-term population survey at this site has revealed some direct toxic effects on reproduction (e.g. egg shell quality and embryo mortality), but major negative impacts on birds are secondary effects arising via changed food webs and diet quality of birds. Environmental pollution has changed the numbers of some key nutritional food items of insectivorous birds, such as calcium-rich snails and carotenoid-rich caterpillar larvae. More attention should be paid in future to explore such secondary pollution effects, since they cannot be revealed just by assessing pollutant levels in wildlife.




Martin Lodenius, Tapio Solonen

The use of feathers of birds of prey as indicators of metal pollution

Department of Environmental Sciences, University of Helsinki.

As metals to great extent are excreted to feathers and these may be acquired without harming living birds, feathers are ideal for monitoring purposes. Birds of prey are on the top of food chains and may thus be used as indicators of environmental pollution. Food is probably the most important factor influencing the levels of metals in feathers. Others are age, sex, time of year, nutritional status and migration. There is a considerable variation in different parts of the plumage. As the variation is lowest in feathers of nestlings these could preferably be used for monitoring purposes. Mercury is especially bioaccumulated in aquatic food chains. Relations to anthropogenic emissions and time trends are of special interest in monitoring surveys. The use of museum samples may give good evidence of time trends but the possibility of external contamination must be taken into account. Different species should be used for different food webs. The mercury level in feathers of the Tawny Owl in southern Finland was clearly lower (mean 0.5 mg/kg) than that for raptors of terrestrial food chains. In the Goshawk, Sparrowhawk and Common Buzzard the concentrations were intermediate (means 1.4, 2.0 and 1.2 mg/kg, respectively) while the level was highest (mean 4.0 mg/kg) in the Osprey which feed almost entirely on fish. Elevated levels of mercury were recorded in the Sparrowhawk from the second half of the 20th century while the concentrations from late 1970's and early 1980's were somewhat lower. For the Kestrel no time trend could be detected.




Saila Sillanpää, Juha-Pekka Salminen, Tapio Eeva

Pollution-related changes in carotenoid-based plumage coloration and fluctuating asymmetry of Great Tit nestlings - roles of food quality and quantity

University of Turku.

The yellow carotenoid-based plumage coloration of Great Tit (Parus major) nestlings is found to be paler in polluted and urban environments. The roles of direct toxic effects and indirect effects via changed food chain are, however, not well understood. We tested three hypotheses that could explain the variation in plumage color and fluctuating asymmetry (FA) in an area polluted with heavy metals: (I) deficiency of carotenoids in diet, (II) condition dependent expression of carotenoid-based plumage color (III) role of carotenoids in FA. Heavy metal levels did not explain the variation in tissue carotenoid concentrations and was not related to plumage coloration. The numbers and carotenoid concentrations of caterpillars were positively associated with circulating plasma carotenoid level of nestlings. Nestlings were in worse condition in the polluted area, but there was no evidence for carotenoid-based coloration to be a condition-dependent trait in P. major nestlings. Our results support the hypothesis that the primary reason for pollution-related variation in plumage color is carotenoid deficiency, not condition-dependent color expression. High carotenoid content in the diet enhanced FA in tail feather length, but not FA in tail feather mass. Our study emphasizes the importance of indirect effects of environmental pollution on birds.




Miia Koivula, Mirella Kanerva, Tapio Eeva, Mikko Nikinmaa

Comparison of EROD activity and redox status in different passerine species

University of Turku, Department of Biology.

Interspecific differences in animals' defence mechanisms against toxic substances are currently poorly understood. EROD is an important biomarker of environmental contamination and it has an important role in defence against toxic chemicals. It can be related to different interspecific feeding habits and the differences may be expressed as different adaptability to survive in contaminated environments. Enzyme activities were compared among passerines species to see if there is interspecific variation in EROD activity and redox status in relation to their diet and year cycle. Migratory insectivores had higher EROD activity compared to granivores. We hypothesize that the normal diet of migratory insectivores contains a wider range of natural toxins, which may have affected the evolution of enzyme activities. On the other hand, narrower and less natural toxins containing diet might explain why the efficiency of detoxification system remains lower in granivores. Redox status (a balance between pro-oxidants and antioxidants) was measured by using glutathione and antioxidant enzymes. Insectivores showed lower enzyme activities compared to granivores and diet seemed to affect glutathione metabolism more than migration status. We suggest that species-specific variation in EROD activity and redox status could be used to identify the most vulnerable species to environmental contamination.




William Velmala, Tapio Eeva, Esa Lehikoinen, Martti Virolainen, Toni Laaksonen

Effects of non-breeding season conditions on adult survival in Pied Flycatchers

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

Migratory birds are exposed to effects of climate change on a large spatial scale from breeding grounds to stop-over and wintering grounds. The weather conditions, predominantly the amount of rainfall, in the wintering grounds have been shown to affect population size in a variety of long-distance Palearctic and Nearctic migrants. Furthermore, some recent studies demonstrate the relationship between non-breeding season conditions and different measures of fitness in migratory birds. However, relatively few studies have been conducted to assess the effect of environmental conditions to adult survival, which is one of the key factors contributing to population dynamics. We analyse capture-recapture data from Pied Flycatcher populations in southern Finland from the last 30 years in order to establish adult survival rate. Non-breeding season conditions were estimated through NDVI (normalized difference vegetation index) values from tropical West Africa, where Pied Flycatchers spend their winter. The NDVI procedure identifies areas of green vegetation and their intensities, which on one hand reflect the amount of rainfall and on the other hand predict abundance of insects consumed by Pied Flycatchers. By comparing the annual adult survival and the non-breeding season conditions, we can understand seasonal interactions to population dynamics.




Céline Arzel, Mia Rönkä, Aurélie Davranche, Johan Elmberg, Matthieu Guillemain, Lennart Saari, Kalle Rainio, Esa Lehikoinen

Are ducks able to adapt their migratory habits to environmental change?

University of Turku, Section of Ecology.

In order to predict waterfowl population changes due to variation in climate conditions, and habitat availability it is necessary to precisely understand the mechanisms driving their annual cycle. This is particularly challenging in migratory birds as they encounter a huge variety of habitats along their migratory routes, and different factors might affect their demographic parameters at different stages of their life-cycle. In this perspective spring migration stands out as a crucial period. During spring migration birds need both to complete their migration and to prepare for subsequent reproduction. An understanding of long-term factors influencing the timing of breeding in migratory birds is particularly important in order to predict how they might respond to future environmental changes. Anatidae are particularly interesting to study as they offer a wide variety of migratory strategies. We discuss some of the factors that are likely to affect individual choices and thus play a role in the evolution of migration. Based on long-term data sets, collected over 30 years, in the Archipelago Sea, SW Finland, we also offer a first insight into the changes in their spring arrival and breeding success of ducks in relation to environmental conditions.




Johan Ekroos, Markus Öst

Impacts of climate and parental condition on survival in a declining Eider population

Aronia Coastal Zone Research Team, Ekenäs, Finland.

Seabirds generally exhibit a low reproductive rate, which is compensated by a long expected life-span. In such species, an increase in adult mortality may have pronounced consequences for the population dynamics. Recent results on the Eider (Somateria mollissima) indicate that female mortality has increased over time in the Baltic Sea area. In an attempt to understand the recent dramatic population decline of the Finnish eider population, we explore the survival of breeding females over a long-term study period (1990-2010) at Tvärminne, SW Finland. Apart from climatic conditions, we expect body condition to affect both the survival probability and fecundity of breeding females. Our results show that both body condition and clutch size exhibit marked inter-annual variation with no trends over time. However, females found breeding only during one breeding season had poorer body condition and produced smaller clutches than those females that bred during at least one subsequent season. Average female condition and clutch size were particularly low after severe winters. Finally, we present some preliminary results from a mark-recapture survival analysis, which clarifies how female body condition and climate factors jointly affect the survival of breeding eiders.




Pekka Helle, Harto Lindén, Marcus Wikman

Recent changes in finnish grouse populations

Finnish Game and Fisheries Research Institute, Finland.

Nationwide quantitative grouse censuses have been performed in Finland for nearly 50 years, providing valuable information on capercaillie, black grouse, hazel grouse and willow grouse population dynamics. Line transect counts with three persons are undertaken in forested areas in August which is prime time for counting: census efficiency is relatively high and young birds are still together with their parent(s) and parameters of reproductive output are available (juvenile/adult ratio, mean brood size, proportion of females with brood). In addition, an estimate of adult sex ratio for capercaillie and black grouse is obtained. Average densities of all grouse species decreased considerably from 1960s to 1980s, about 20-60% depending on species and area. During that period all species had an almost clockwork precision in cyclic fluctuations with 5-7 year cycle length, and the synchronicity of within-species and between-species fluctuations was high. During the past two decades the density trends have been only slightly decreasing, fluctuations being rather erratic than cycling. The level of synchronity among areas has decreased, too. There is no long-term trend in the reproduction of grouse in terms of juvenile/adult ratio during the past decades but it seems that the proportion of females with brood has slightly increased whereas the mean brood size shows the opposite.




Matti Koivula, Fiona Schmiegelow

Post-fire logging alters boreal passerine assemblages

Finnish Forest Research Institute.

Post-fire salvage logging has become routine in recently burned boreal forests of North America. While salvage logging may recoup some economic losses due to wildfire, it also alters the forest biota. Most documented ecological effects of salvage logging are negative, but some open-area associated taxa benefit from tree removals. To study avian responses to salvage logging across a variety of forest types, we conducted transect counts at 24, 625-ha experimental landscape units within a large wildfire in Alberta, Canada in 2003-04. Most of the variation in passerine assemblage structure could be explained by distinguishing coniferous and mixed-wood forests, and salvage logging altered the structural composition. Species richness in salvaged areas was significantly lower than in old mixed-wood forests that were burned but not harvested. GLMMs for the species richness of different functional groups of passerines suggest that these changes were due to decreases in tree-nesting species and increases in ground-nesting omnivores in salvaged areas. Surprisingly, cavity-nesters were little affected, possibly due to the fire-generated pulse of dead wood in adjacent, unlogged forests. These results suggest that in order to maintain locally rich passerine assemblages within salvaged wildfires, intact mature forests should be retained to support species associated with closed forests.




Esa Lehikoinen

Migratory birds as climate change sensors

Department of Biology, University of Turku.

Success of migratory birds is based on careful evolutionary "mapping" of optimal migratory routes, strategies and timing. Natural variability of climate is the cause of variation in these traits within populations offering material for evolutionary adaptation. Individual plastic responses also improve the chances of birds to perform migration so that breeding and survival are not seriously affected. The rate of climate change is predicted to increase from that in the last 40 years, which has created concerns about the capability of birds to withstand the change either by plastic response or natural selection. In contrast to sedentary species, migratory birds have to phase varying climate and habitat changes in vast areas during their annual journeys. We report here results based on a global database of 3827 time series on first arrival (FAD) and median arrival dates (MAD) from 19 countries on 455 species, which was collected by August 2009. FAD suggests advancement by 2.8 days/decade, and MAD 1.8 days/decade. We discuss the methodical and biological reasons to this difference. It is important to improve the precision of response estimates for use in predicting the future changes and migratory birds' chances to cope with accelerating climate warming, if realized.




Andreas Lindén

What do first arrival dates tell us?

University of Oslo, Department of Biology, Centre for Ecological and Evolutionary Synthesis, Oslo, Norway.

Birds adjust their timing of migration to climate change. Unravelling the mechanisms of such phenological responses, requires explicit quantitative estimation of the distribution of phenological events. First arrival dates (FAD) are very commonly used data in phenological studies, probably due to numerous long time series available. However, population size and observation effort are known to bias the observed FAD:s in a non-trivial manner, hampering any attempt for quantitative estimation of phenology. Further, the biological interpretation of analyses with FAD:s as response variables is vague and qualitative. Using simulation, I here demonstrate how FAD:s are likely to be related to population size and observation effort. The results suggest that analyses of FAD:s always should account for population size and/or observation effort, whenever available. Fitting phenological distributions functions provides an explicit approach for combining FAD:s and other types of complementary data, in a coherent quantitative model that can be fitted with regular maximum likelihood techniques. While detailed daily data (e.g., from bird observatories) provides information about the distribution shape, day-to-day variation and number of birds, FAD:s provide extra information about early phases of migration and can also allow estimation of phenology beyond the time span of the more detailed data.




Antero Järvinen

Changes in northern nature: Pied Flycatcher facts from a LTER site in Finnish Lapland

Kilpisjärvi Biological Station, University of Helsinki.

The backbone of ecology is built on knowledge gained during long-term monitoring programs. At present, however, an inconvenient truth is that we have many hot theories of the effects of global warming on ecosystems, but too few cold facts. Science needs theories, but they cannot be tested without high quality data. Kilpisjärvi Biological Station (University of Helsinki) is famous for its exceptionally long data sets of many aspects of northern nature. These data can be used to test hot theories. The Pied Flycatcher population of the Kilpisjärvi area, northern Finnish Lapland (69°N), has been studied since 1966. Thus, this 45-year (1966-2010) study is apparently long enough to span the periodicity of the normal dynamics of the ecosystem. In addition to long-term dynamics and possible trends in the annual mean values of essential reproductive traits of the Pied Flycatcher breeding near the northern and altitudinal distribution limit of the species, my presentation examines changes in northern nature and whether they are due to global warming or not. Huge annual variation seems to overshadow trends, and cyclic changes may be more important than linear ones.




Patrik Karell, Kari Ahola, Teuvo Karstinen, Jari Valkama, Jon Brommer

Climate change drives microevolution in a wild bird

University of Helsinki, Deptartment of Biosciences.

Climate warming changes the environment of most organisms and is expected to lead to a change in selection pressures with microevolutionary consequences that allow the adaptation of organisms to this new environment and thereby long-term population persistence. However, evolutionary response to a quantified selection pressure driven by recent climate change has not been empirically demonstrated in a wild animal population. We use detailed individual-based long-term data from 28 years in a study population of Finnish Tawny Owls to show that pheomelanin-based plumage colouration is a highly heritable trait. Capture-mark-recapture survival analysis shows that strong viability selection against the brown morph occurs only under snow-rich winters. Winter conditions have become milder in the last decades, leading to a marked reduction in selection against the brown morph. Concurrent with this diminishing selection, the proportion of the brown morph increased rapidly in our study population during the last 28 years and in the nationwide ringing data during the last 48 years. Our study demonstrates that microevolutionary response to recent climate change occurs and it provides an important benchmark estimate of the evolvability of wild populations to climate change.




Päivi Sirkiä, Martti Virolainen, Esa Lehikoinen, Toni Laaksonen

Melanin coloration has temperature-dependent effects on breeding performance in the Pied Flycatcher

University of Turku.

Variation in melanin-based coloration is often associated with differences in temperature-related physiology and behaviour. Understanding of these interactions is essential in predicting the consequences of climate change. Male plumage coloration of the Pied Flycatcher (Ficedula hypoleuca) varies from completely brown to black. We used 25-year data set to examine whether different male phenotypes are adapted to breed in different environmental conditions. The effects of temperature on the relative success of different male phenotypes varied between different phases of breeding. The reproductive output of black males was highest when it was cold during egg-laying but warm during the nestling period, whereas the fledgling production of brown males was highest when it was continuously warm. Further the predicted relative breeding success of black and brown males was associated with the yearly varying proportions of black and brown males observed in southern Finland during 1954-2008. Our results thus indicate that variable weather conditions are maintaining variation in phenotypic characters of male Pied Flycatchers. Climate change may alter male phenotype frequencies in this species. The directions of possible changes are however complicated because the overall fledgling production is dependent on the interactions between weather conditions during different phases of breeding.




Anssi Vähätalo

Milder winters have expanded the wintering range of Tufted Ducks in the Baltic Sea

Aronia Coastal Zone Research Team, Ekenäs, Finland.

A winter bird survey covering 1957-2010 shows a several hundred-fold increase in the number of wintering Tufted Ducks (Aythya fuligula) in Âland Islands of Baltic Sea from a typical 14 ducks prior 1990 compared to thousands counted in the first decade of second millennium. Because Âland Islands represent the northern limit for wintering Tufted Ducks, the increase in the number of ducks indicates a northward expansion of wintering range. The expansion of wintering range occurred simultaneously with the decreasing maximum ice extent of Baltic Sea and the increasing (2.8°C 60 yr-1) winter temperatures of Âland Islands. The wintering Tufted Ducks concentrated on a few coastal locations. During the recent mild winters at the most favored new wintering site, the density of ducks integrated over winter period exceeded by an order of magnitude the bird-day densities of Eider (Somateria mollissima), the most abundant breeding benthivorous duck in the study region. On the basis of published food-consumption, one can estimate that during mild winters the newcomer of winter-bird fauna consumes a remarkable portion of standing crop of benthic fauna they feed upon at the most favored wintering site. Altogether, this study indicates that a milder climate can shift the range of animals to new ice-free regions, where the high densities of immigrated animals can consume a remarkable part of their food and change the structure of benthic communities, which would be sheltered by ice in a colder climate.




Aleksi Lehikoinen

Climate change has altered the predation pressure of migratory passerines

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

Climate change has been shown to cause phenological changes. These changes are not necessary similar between species and may cause mismatches between prey and predator. Eurasian Sparrowhawk Accipiter nisus, the main predator of passerines in Northern Europe, has advanced its autumn migration dates by about ten days over the past 30 years. However, it's not known whether Sparrowhawks are tracking the migration times of their prey or if the advanced departure of Sparrowhawks has lead to changes in predation pressure of migrating passerines. Based on median departure dates of 41 passerines, I found that early migrating passerines tend to advance and late migrating species delay their departure, but none of the species have advanced their departure as much as the sparrowhawks. This has lead to a situation of increased predation pressure of early migrating long-distance migrants (LDM) and decreased the predation of later departing, short-distance migrants (SDM). These findings highlight the growing list of problems of declining LDM populations caused by climate change. Autumn migration of SDMs, the populations of which are doing better, is, on the other hand, becoming increasingly safer. These results also demonstrate that the autumn phenology of passerines shows a very conservative response to climate change.




Markus Ahola, Toni Laaksonen, Tapio Eeva, Esa Lehikoinen

Roles of climatic factors and breeding density in natural selection on laying date and on clutch size in Pied Flycatcher

University of Turku.

Timing of reproduction and clutch size are important determinants of breeding success especially in seasonal environments. Several bird population studies have shown changes in reproductive traits as well as in natural selection on breeding time along with the climate warming. However, it has been rarely studied how climatic, or other, variables are actually connected to the natural selection. We studied variation in natural selection on laying date and on clutch size in relation to measures of spring phenology and population density in a long-term data-set on Pied Flycatchers in SW-Finland. We found 1) that there was stronger selection for early laying when the breeding density of the population was high, suggesting that early breeding is not necessarily beneficial as such, but its importance is emphasized when high population density increases competition. 2) Early breeding was favoured when the pre-breeding period was cool, which may indicate advantage for the fittest individuals in harder conditions. 3) In the middle of 20th century, selection was for large clutch size, which however ceased later. Further explanations are discussed, but our results call for paying attention to demographic factors such as breeding density when studying natural selection in relation to environmental variables.




Emma Vatka, Markku Orell, Seppo Rytkönen

Warming climate has advanced breeding and improved synchrony with the food peak in a boreal passerine

University of Oulu.

Due to the climate change, the timing of breeding in the Willow Tit (Poecile montana) and timing of the caterpillar food peak have advanced in a boreal forest environment. In northern latitudes climate warming has not induced asynchrony between the timing of breeding in willow tits and the caterpillar food availability, in fact, the opposite has happened. The timing of egg-laying, as well as timing of the food peak, is well explained by the temperatures of spring. In addition, the timing of egg-laying is influenced also by the temperatures of preceding autumn and winter. We report results of the influence of the changed synchrony pattern on breeding success and discuss the role of the ambient temperature as a proximate and an ultimate factor in the timing of breeding.




Elina Mäntylä, Tero Klemola, Toni Laaksonen

Birds help plants - a meta-analysis of top-down trophic cascades caused by avian predators

University of Turku, Section of Ecology, Department of Biology.

The tritrophic interactions between plants, herbivores and avian predators are complex and prone to trophic cascades. We conducted a meta-analysis of original articles that have studied birds as predators of invertebrate herbivores, to compare top-down trophic cascades with different plant responses from different environments and climatic areas. Our search found 29 suitable articles, with a total of 81 separate experimental study set-ups. The meta-analysis revealed that plants benefited from the presence of birds. A significant reduction was observed in the level of leaf damage. The presence of birds also positively affected the amount of plant biomass, whereas effects on plant growth and plant mortality were negligible. There were no differences in the effects between agricultural and natural environments. Similarly, plants performed better in all climatic areas (tropical, temperate and boreal) when birds were present. Moreover, both mature plants and saplings gained benefits from the presence of birds. Our results show that birds cause top-down trophic cascades and thus they play an integral role in ecosystems.




Juhani Rinne

Wood Warbler (Phylloscopus sibilatrix) as a cost effective indicator for common forests

In nature conservation, different indicators systems for valuable forests have been applied. However, there seems to be no such indicators for systematic evaluation of common forests as experienced by humans. For example, in the Central Park of Helsinki different groups of people are involved in construction, winter sports, golf, forestry, traffic (cycling), nature conservation, health care, parkland building and enjoying the nature. Except for the people enjoying the nature, these groups have their own measurement systems to develop the area. It is generally thought that human beings prefer areas of savannah type. The landscape should be open with weaker undergrowth, trees and rich natural conditions with some variations. In extratropical conditions, these requirements fit rather well with those of the Wood Warbler. In this article, it is proposed that the number of the primary singing places of the Wood Warblers should be used as one indicator of forests. This indicator is cost effective. It is applicable more widely. For instance, the population of the Wood Warbler has rapidly decreased in Europe presumably reflecting the deteriorating condition of the forests. The background and the features of the indicator will be described in more detail.




Suvi Ruuskanen, Blandin Doligez, Natalia Pitala, Lars Gustafsson, Toni Laaksonen

Long-term fitness consequences of high yolk androgen levels: sons pay the costs

University of Turku, Section of Ecology, Department of Biology.

Early growth conditions, for example hormonal environment, may have long-lasting effects on behaviour and phenotype, with subsequent fitness consequences. In oviparous species, yolk androgens have been shown to affect various offspring traits in the short term, but fitness consequences for either offspring or parents, a prerequisite for studying the adaptiveness of this maternal effect, have been little studied in the wild. We experimentally elevated yolk androgen levels in a wild population of Collared Flycatchers (Ficedula albicollis) to investigate the long-term effects of yolk androgens on offspring recruitment and parents' return probability and timing and success of breeding during breeding season(s) following the manipulation. We found that yolk androgen elevation lowered the recruitment rate of male, but not female offspring. Androgen manipulation had no effect on the breeding success of offspring of either sex. Furthermore, elevation of yolk androgen level had no effect on the return rate or breeding success of the parents. Our results thus indicate that high yolk androgen levels may impose a potential direct fitness cost for male offspring, but no long-lasting additional fitness costs for the parents. Such costs can constrain androgen allocation and select for sex-specific allocation mechanisms.




Sari Raja-aho, Petri Suorsa, Minna Vainio, Mikko Nikinmaa, Esa Lehikoinen, Tapio Eeva

Body condition is associated with adrenocortical response in the Barn Swallow (Hirundo rustica L.) during early stages of autumn migration

Section of Ecology, Department of Biology, University of Turku.

Migration is an energy-demanding life-history period and also a significant population-limiting factor of long-distance migratory birds. It is important to understand how corticosterone, the main energy regulating hormone in birds, is associated with behavioral and physiological changes during migration. According to the migration modulation hypothesis (MMH), individual birds may express elevated levels of baseline corticosterone to facilitate fuelling, but down-regulate the adrenocortical response in order to protect skeletal muscles from the catabolic effects of the hormone. We measured the baseline and stress-induced levels of corticosterone in Barn Swallows (Hirundo rustica L.) during early stages of autumn migration. We found that, while barn swallows clearly responded to the capture and handling stress by increasing the corticosterone level, the strength of this acute response was related to their energetic condition: birds with high body mass responded more rapidly and had lower peak values of corticosterone than lighter birds. Further, the baseline levels of corticosterone correlated negatively with the magnitude of the adrenocortical response. Barn Swallows did not show elevated baseline levels of corticosterone in the course of autumn, which suggests that, instead of fuelling, the birds were actively migrating. Our results indicate that MMH also applies to aerial feeders, whose foraging habits differ from model birds of previous studies.




Karen Wiebe

Influence of spring temperatures and individual traits on reproductive timing and success in a migratory woodpecker

University of Saskatchewan, Department of Biology, Canada.

I investigated the effect of spring temperatures, female age and body condition on the timing of laying in migratory woodpecker, the Northern Flicker (Colaptes auratus), and looked at the relationship between laying date and reproductive success. Average annual laying dates in the population recorded over 12 years were not related to the NAO or PNA climate indices but were earlier when average daily temperatures along the migration route of flickers along the Pacific coast of North America were warmer. The strongest negative correlation between laying dates and ambient temperatures occurred after the arrival of most birds on the breeding site, suggesting that the ability of females to accumulate resources for egg laying was an important determinant of laying times. Egg-laying advanced by 1.15 d for every degree warmer on the breeding grounds. Laying dates of individuals advanced as females aged from 1 to 3 years and females in better body condition also laid earlier. However, there was no interaction between female age and ambient temperature suggesting the age classes had equal capacity to respond to environmental change. Reproductive output declined seasonally as a result of clutch size declines and not reduced fledging success. This suggests there is no ecological mismatch linked to prey availability for flickers and that individuals could benefit by laying earlier if spring temperatures allow.




Jukka Rintala, Juha Tiainen

The effects of weather and density-dependence on breeding of migratory passerine based on long-term and large-scale monitoring data

Finnish Game and Fisheries Research Institute.

Delayed density-dependence, climate effects and observation errors of population counts were studied in a migratory passerine bird (the Finnish starling Sturnus vulgaris) on the basis site-by-year structured national nestling ringing data (1951-2009). Annual national-level series of population change indices and means of brood size and breeding time were derived. High values of NAO and spring temperature were related to advances in ringing date, indicating earlier breeding during the years of relatively mild winter and spring weather. This pattern suggests that the long-term climate warming may have improved longevity of starlings (slightly compensating the population decline caused by a decline of farmland habitats rich in starling food). Earlier breeding reflected to increases in mean brood size. Based on a 1-year lagged autoregressive state-space model, apparent density-dependent regulation was found in addition to regulatory impacts due to (environmental and/or demographic) stochasticity. Population dynamical patterns were not hidden by observation errors in population size indices. State-process growth rate variation converged well with observed brood size variation, suggesting that brood size is density dependent. The residual variation included climate effects and probably also density dependent (beyond ringing-age) fledging success and fledgling survival.




Satu Lampila, Katja Kangas, Ari Nikula, Vesa Nivala, Markku Orell

Determinants of nest site selection of the Willow Tit

Department of Biology, University of Oulu.

We studied the nest site selection of the willow tit in a fragmented commercial forest in northern Finland. The main goals in this study were to assess the suitability of remote sensing data for the analysis and to determine the most important habitat types for the willow tits during the breeding season. Three different sampling scales were used: territory core (1 ha), foraging area (4 ha) and winter territory scale (34 ha). Several habitat variables, e.g. the percentage of different habitat types, distance to the nearest ditch and number of decayed birch trees available for excavating the nest hole, were measured from nest sites and randomly selected non-breeding sites. Mean patch size and amount of open edge within the studied plots were estimated to consider the possible habitat fragmentation effects. Preliminary results show that the presence of decayed birch trees is the most important factor explaining the nest site selection and the other variables have only minor role. The common forest management practise of removing deadwood may thus have detrimental effect on willow tit breeding. The next step of this study will be relating individual fitness (e.g. breeding success) to habitat quality.




Hannu Pöysä, Robert Clark, Pekka Runko, Antti Paasivaara

Timing of breeding in short-distance migrant birds and the mismatch hypothesis: offspring recruitment patterns in European Goldeneyes Bucephala clangula

Finnish Game and Fisheries Research Institute.

Mismatched timing of breeding occurs when organisms are unable to adjust breeding dates to exploit resources that affect fitness. In some bird species, lower reproductive success is associated with warmer springs when food resource peaks occur prior to the peak demands of growing young. A mismatch may also arise in long-distance migrant bird species when environmental cues experienced during spring migration are decoupled from conditions on breeding grounds. However, short-distance migrant bird species that store reproductive nutrients prior to breeding or that produce precocial, self-feeding offspring may avoid or buffer adverse effects of resource mismatches. Furthermore, reduced short-term reproductive success could be offset by higher future recruitment of surviving offspring. We evaluated whether recruitment of locally-hatched female offspring was related to the strength of mismatched timing of breeding for individually-marked adult female Common Goldeneyes (Bucephala clangula, a short-distance migrant) from a site in central Finland. We found that older, early-nesting females with good body condition recruited the most female offspring. Offspring recruitment was unrelated to the extent of mismatch. Our results seem most consistent with a hypothesis that short-distance migrant species with precocial offspring may have the capacity to respond appropriately to changing environmental conditions prior to onset of breeding.




Sari Suhonen, Petri Nummi, Hannu Pöysä

Long term change of habitats and duck distribution in boreal lakes

Department of Biosciences, University of Helsinki.

We studied changes in vegetation and habitat use of Mallard, Common Teal and Goldeneye pairs and broods in 51 lakes in Evo. Vegetation was mapped in 1989 and 2009, duck data are from years 1989-1991 and 2007-2009. Vegetation in the lakes has not changed systematically between 1989 and 2009. However, some notable changes were found. Lakes that had become more luxuriant are near human settlements or are influenced by humans in other ways. Lakes that had become poorer were commonly small forest ponds. The beaver influence was strong. From 12 beaver lakes, 11 were more luxuriant during the beaver flood. Changes in the vegetation of flooded lakes were significantly larger than the changes in normal lakes. The number of lakes which ducks used reflected population size, but the luxuriance of the used lakes did not clearly correlate with the size of the population. Goldeneye pairs and broods used significantly poorer lakes in 2007-2009. Teal pairs used slightly more luxuriant, and broods much poorer lakes in 2007-2009. Mallard habitat use and population size remained unchanged between the two study periods.




Kim Jaatinen, Markus Öst, Aleksi Lehikoinen

Adult predation risk drives shifts in parental care strategies: a long-term study

Aronia Coastal Zone Research Team, Ekenäs, Finland.

Grouping provides antipredatory benefits and therefore aggregation tendencies increase under heightened predation risk. In socially breeding groups, however, conflicts over reproductive shares or safety tend to disintegrate groups. Group formation thereby involves a balance between the antipredatory benefits and destabilizing effects of reproductive conflict. We model group formation within brood-rearing coalitions of female Common Eiders (Somateria mollissima), generating predictions about the relative frequencies of solitary versus cooperative parental care modes. We also model the magnitude of the dilution effect as a function of female group size and predation risk. The model predicted that i) cooperative brood care becomes more prevalent and, conversely, solitary brood care less prevalent under heightened predation risk and, ii) group sizes increase concomitantly. After controlling for female body condition, our 13-year data set supported both predictions, where heightened predation risk directed at nesting females increased the relative frequency of cooperative brood care and decreased that of solitary brood care. Increased female nesting mortality resulted in larger groups of cooperative females. These results show that the predation risk of incubating females has important long-term implications for later grouping and parental care decisions.




Toni Laaksonen, Päivi Sirkiä, Paula Lehtonen, Graig Primmer

Signals of selection in geographic colour variation of the Pied Flycatcher

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

We study mechanisms maintaining both geographic and within-population variation in the plumage coloration of a passerine bird, the Pied Flycatcher (Ficedula hypoleuca). The dorsal coloration of males in this species varies from dull brown to black. It has been suggested that the brown phenotype is selected for in areas of sympatry with the closely related collared flycatcher (which is black) because it reduces hybridisation and interspecific competition. The black phenotype predominates in allopatric areas, where it may be selected for. Surprisingly, geographic variation in other conspicuous male traits, such as the sizes of white patches or UV reflectance, has not been quantified. With a Europe-wide network of collaborators, we have collected standardised data on plumage coloration patterns and fecundity selection for them in different parts of the species' range. We have also collected molecular genetic data for analysing the population genetic structure of the species, which appears to exhibit a clear gradient of differentiated populations in the south and a panmictic population in the north. The results of these studies should provide a better understanding of the evolution of plumage coloration patterns in a spatial ecology context and of the factors maintaining the huge variation in coloration.




Heli Siitari, Rauno Alatalo, Miina Kovanen, Christophe Lebigre, Gilbert Ludwig, Pekka Rintamäki

Sexual selection and conservation in the lekking Black Grouse

University of Jyväskylä.

Our group previously led by Professor Rauno Alatalo has investigated lek as a mating system and individual fitness in Black Grouse (Tetrao tetrix) since 1980's. Lek really seem to test the viability of the males, and females choose their mates based on several behavioural, physiological and morphological cues. Mating is highly skewed among the males, and old males usually keep the central territories on the lek. Surprisingly, all the broods are mainly sired by one male only, which is quite uncommon among the birds. According to our recent results female dispersal is the main mechanism to avoid inbreeding. Lek size is important for attracting new females to the area for breeding, since females prefer larger leks to mate. However, males do not form kin groups when lekking. Major of the male territory changes occur during the autumn, when hunting is allowed. These are important things to realize when planning hunting in Finland. My presentation summarizes the main results of this long-term individual-level study.




Matti Kervinen, Christophe Lebigre, Anssi Lipponen, Heli Siitari

Telomere dynamics and individual lifetime fitness in Black Grouse (Tetrao tetrix)

University of Jyväskylä.

Understanding the variation in individual fitness associated with sexual selection requires identification of the factors underpinning individual performance. Telomere studies have usually reported a shortening in telomere length with age, but the relationship between telomere shortening and individual reproductive success remains unclear. The recent development of real-time quantitative PCR (qPCR), enables relatively fast and cheap measurement of telomere length, thereby facilitating the analysis of large long-term datasets. Using this method, we quantified changes in telomere lengths of 100 male Black Grouse males over their lifespan (3 to 6 years). In this lekking species, male mating success is highly skewed, females preferring dominant and most viable males. Our results reveal that individual variation in the initial telomere length and the rate of changes in telomere length are substantial. This crucial step will enable us to relate these measures to male lekking performance and lifetime mating success and to test whether changes in physiological condition (stress) are related to the individual rate of changes in telomere length. Such analysis is crucial because differences between high- and low-quality males in telomere characteristics could be one mechanism through which females gain indirect benefits from their mate choice.




Suvi Ponnikas, Laura Kvist, Markku Orell, Torsten Stjernberg

Population genetics of the White-tailed Eagle in Finland

University of Oulu.

The White-tailed Eagle have gone through two severe bottlenecks in Finland during the recent history, first due to the persecution and second time due to the accumulation of the harmful chemicals in the environment. At the lowest, at the beginning of the 1970's the population of the White-tailed Eagle was only 45-50 pairs, several of them incapable to reproduce. Strong protection activities, such as serving chemically pure winter food at feeding sites, habitat management and provisioning of artificial nests, has had resulted as recovery of the species. Estimation of the population genetics of the species is crucial since the genetic structure of the population may have changed when it went through the bottlenecks in addition to the likely changes in genetic diversity. We used 8 polymorphic microsatellite loci and DNA-samples collected from chicks during the ringing procedure between years 2003-2007 to study the genetics of the Finnish White-tailed Eagle population. We studied the genetic diversity by calculating e.g. the allele richness and heterozygosity. Population structure and gene flow were estimated by various methods including the FST- and RST-based and Bayesian-model based clustering methods. Also isolation by distance was tested.




Ville Vasko, Toni Laaksonen, Jari Valkama, Erkki Korpimäki

Breeding dispersal of Eurasian Kestrels under temporally fluctuating food abundance

University of Turku, Section of Ecology, Department of Biology.

Condition-dependent dispersal strategies are expected to evolve in environments, where benefits of dispersal vary in space and time. We examined factors affecting breeding dispersal distances in Eurasian Kestrels (Falco tinnunculus) subsisting on multi-annually and cyclically fluctuating voles as their main food. We attempted to avoid traditional bias in dispersal studies by having large study areas and by taking detection probabilities into account. We observed 320 dispersal events of male and 215 events of female Kestrels from our study areas in western Finland during 24 years. After correcting for detection probability, the estimates of mean dispersal distances for both sexes increased roughly two-fold, being clearly higher for females than males. At the population level (cross-sectional model), both sexes showed a condition-dependent dispersal pattern by dispersing longer distances when food was scarce. Vole abundance in the spring of settlement was more important in determining average dispersal distances than vole abundance in the previous autumn. At the individual level (longitudinal model), only females responded to vole abundance. Individual males did not respond, which might be explained by sampling effects. Our results show that the dispersal distances of kestrels at northern latitudes depend both on individual properties (gender, age, and individual tendency to disperse) and environmental conditions (temporal variation in main food abundance).




Heidi Björklund, Toni Laaksonen, Jari Valkama

Birds of prey in changing environment

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

Modern forestry has changed the breeding habitat of forest dwelling diurnal birds of prey. Forest structure has become younger, area of old forests fragmented and stout trees suitable to support big twig nests have been removed. This may result in increased interaction, for instance in competition for nests, and thereby reduced breeding success especially among smaller species. Finnish Museum of Natural History has coordinated the nationwide survey of common birds of prey for four decades. Volunteer ringers inspect every year thousands of potential nest sites and collect detailed information on breeding parameters and nests. Based on this data, we examine the possible change in breeding output of Honey Buzzard (Pernis apivorus), Goshawk (Accipiter gentilis) and Common Buzzard (Buteo buteo) during the survey period. We inspect also the lifespan of nests, as the forestry practices presumably have an effect on the occupancy of territories.




Kristiina Mannermaa

The history of Cormorants (Phalacrocorax carbo) in the Baltic Sea area based on archaeological data: present knowledge and future research

Department of Philosophy, History, Culture and Art Studies, University of Helsinki.

Cormorants (Phalacrocorax carbo) have a long breeding history in the Baltic Sea region. The most earliest archaeological finds in Denmark and Sweden date to ca. 9000 BP. The amount of cormorant finds increases during younger periods of the Stone Age, ca. 8000 BP onwards in Denmark, and ca. 5000-2500 BP in Sweden. The earliest known finds in Poland date to at least 10 000 BP, in Estonia to about 5000-4000 BP and in to Finland about 5000 BP. Cormorants have lived in Northern Germany at least from ca. 9000 BP. The colonization history of the two subspecies (P. carbo sinensis, P. carbo carbo) in the Northern Europe and the Baltic Sea region is still poorly known. Historical evidence on breeding P.c. sinensis in Denmark were recorded in late 18th century AD and in Sweden around AD 1850-1900. This may be the earliest known historical data on P.c. sinensis in Scandinavia. According to size measurements of Swedish archaeological cormorant bones, it has been suggested that all Stone Age cormorant finds most likely belong to the subspecies P.c. carbo. However, measurements taken from Danish archaeological bone assemblages suggest that both subspecies have lived in prehistoric times. Therefore, based on present knowledge, we cannot conclude that P.c. sinensis did not exist in the Baltic Sea region in prehistory. An international multidisciplinary project aiming in identification of cormorant subspecies in Northern European archaeological materials by using both measurements and molecular studies (ancient-DNA) has been launched.





ABSTRACTS OF THE POSTER PRESENTATIONS

Kirsi Reponen

Long-term changes in bird size and condition

Department of Biology, University of Turku.

Long-term changes have been detected in the life histories of birds. Global environmental change may induce changes in the timing of different life stages such as migration and breeding. Long-term data is crucial to untangle the complex responses of birds to their changing environment. Global environmental change has the potential to affect the size and condition of birds for example by changing living conditions and food supply. The aim is to study the long-term changes in size and condition of birds as a response to global environmental change. The research is based on extensive and long term ringing and measuring data. A large data set has been collected since the end of 1960s comprising of over 200.000 ringing and measuring occasions. Systematic errors caused by the differences in measuring techniques between individual ringers will be corrected before the analysis. In addition the seasonal effect on the wing length in the form of wearing will be corrected. Differences between sexes will be analysed as well since they might respond in a different way. The results of this study can be used to observe and predict how birds respond to global environmental change.




Sari Suhonen, Petri Nummi

The landscape effect of beaver to breeding ducks in boreal wetlands

Department of Biosciences, University of Helsinki.

We studied the effect of beaver-flooded lakes to the number of the pairs and ducklings of Mallard, Goldeneye and Common Teal in Evo. The data is from 52 lakes and covers the years 1989 to 2009. The lakes have a total of 49,9 km of shoreline of which 1,2-9,3 km (mean 3,6) is flooded yearly. We studied if the amount of flooded shoreline is reflected to the population of ducks in the whole area. We tested if there is an association between the amount of flooded shores and the number of pairs and the amount of ducklings of two age classes. Class 1 were downy ducklings aged 1-3 weeks, and class 2 were ducklings aged 4-7 weeks. Even though there is not much of flooded shoreline, it has a significant positive effect to the amount of age class 1 ducklings of Mallard and Goldeneye. Significant effect for age class 1 ducklings is even stronger when all species are pooled together. It seems that even a small amount of good shore makes a difference to the production. Teal occupies beaver patches so intensively that it seems that the change in the flooded shoreline in the landscape doesn't affect teal production.




Veli-Matti Väänänen, Petri Nummi, Jarmo Laine, Esa Lammi, Teemu Lehtiniemi, Veli-Matti Luostarinen, Markku Mikkola-Roos

Barnacle Geese in Finland - rapid population growth and use of urban areas

Department of Forest Sciences, University of Helsinki.

The population of Barnacle Goose Branta leucopsis has rapidly increased in Finland during 1985-2009. In 2009, the number of barnacle geese was estimated at 3000-3500 breeding pairs. The most important breeding areas are archipelagos around the cities of Helsinki (1280 pairs) and Turku (269). During the first 10-15 years, the goose populations showed only a slow increase. After the mid 1990s populations increased rapidly. Helsinki and Turku were also the most important autumn staging areas with 8 600 and 2 900 geese in 2009, respectively. The breeding habitats of urban geese consist of two parts: the relatively natural archipelago and the urban lawns. We suggest that successful establishment of Barnacle Goose in Finland is due to a combination of low predation rate and good foraging areas. The geese can avoid mammalian predators by nesting in small islands and islets. And, urban lawns and shore meadows offer good grazing habitats for broods. However, in the most densely populated areas the population growth seems to have slightly decreased, which indicates that there may be density-dependent processes going on.




Milla Niemi, Tiina Mäkelä, Niina Jääskeläinen, Ere Grenfors, Petri Nummi

Traffic mortality of birds in southern Finland

Department of Forest Sciences, University of Helsinki.

Traffic can be a significant cause of disturbance and mortality for birds. Previous studies have shown that the annual number of road-killed birds in Finland is several million individuals. We studied the species composition of road-killed birds in southern Finland. Our first study was carried out during the summer of 2004. Once per week, we identified carcasses found on twenty 300-m long study sections. During a ten-week period, we found a total of 40 bird carcasses. There were 22 single species belonging to 13 families. A third of all carcasses were thrushes (Turdidae), and also finches (Fringillidae) were common. Our second study was carried out during the summer of 2008. We identified carcasses on 20 riversides (400-m road sections) and 20 control sections. Weekly counting was performed ten times. We found a total of 50 carcasses representing 24 species and 13 families. Again, the most common family found was thrushes. We found more carcasses on riversides than controls. It seemed that the amount of carcasses associated with traffic volume, although only indicatively. We concluded that road mortality concerns many bird families and needs to be studied in detail in the future.




Andrea Santangeli, Toni Laaksonen, Hannu Lehtoranta

Woodland resource use and raptors: A cost-effective strategy for nest site conservation

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

The conflict between woodland resource use and wildlife has complex socio-economic and ecological implications. As resources committed to nature conservation are often limited, inexpensive participatory programmes may represent a powerful tool for conservation. Such tools have however seldom been considered and applied. We present results from a participatory conservation project run in North Karelia (Finland) from the year 2000. The aim was to preserve nest sites of raptors (Common Buzzard, Goshawk or Honey Buzzard) on private lands subject to intensive forest management. After preliminary surveys to locate raptor nests in the area, landowners were approached and proposed to voluntarily set aside the forest stand with occupied nest. Participation was exclusively based on self-motivation and self-induced values, with no incentives involved. The project was extremely successful, as almost all the approached landowners showed a positive response. The consequences of this conservation intervention on the local raptor population are currently being analysed. Although limited to a local area, these results clearly demonstrate that an inexpensive participatory model can work, at least in some socioeconomic and environmental conditions. Given its potential as a tool for cost-effective conservation, we urge to test and evaluate this approach on a wider scale.




Antti Halkka, Aleksi Lehikoinen, William Velmala

Do long-distance migrants use timing zones to adjust their timing of arrival in spring?

Department of Biosciences, University of Helsinki.

Spring migration and arrival of birds have been shown to be strongly linked to temperature for both short and long-distance migrants in Europe It is, however, less clear where along the route this temperature based adjustment does take place. A widely used method to study this has been to select various temperature station data points along the route. A more precise alternative is to use gridded temperature data. We used a 32 year dataset of bird arrivals of the Hanko Bird Observatory (Finland) and additional published European data to study temperature correlation patterns (monthly data) for a set of long-distance migrants. Some examples are shown. A correlation pattern along in a large part of Europe along the presumed route often emerges. Results vary, but the strongest correlations are often found roughly 500-2000 kms from the bird observatory. We hypothesize, that this correlation zone also roughly defines the location of a timing zone influencing the timing of arrival. As temperature is spatially correlated, the exact location of this zone is difficult to assess. Our results indicate, however, that a timing zone along the spring migration route of long-distance migrants is a common phenomenon, quite extensive, and not typically centred very near the observatory where timing is checked. If a correlation pattern is not very distant, it is probably adaptive in adjusting bird arrival to yearly phenology.




Céline Arzel, Lisa Dessborn, Petri Nummi, Hannu Pöysä, Johan Elmberg, Kjell Sjöberg

Does changing spring phenology affect short and long distance migratory waterfowl similarly?

Department of Biology, University of Turku.

Among waterfowl, most ducks may be considered income breeders due to their small body size and their limited capacity to store energy. Therefore limited access to resources on their breeding grounds is likely to affect their breeding schedule and potentially output. At northern latitudes, ice break up dictates the access to the breeding lakes. An early ice break up allows for early access to the breeding site and its feeding resources, and potentially leading to higher breeding output than after a late ice break up. Short distance migrants are thus more likely to adapt to ice break up conditions than long distance migrants which have to cope with weather conditions en route and local resource accessibility along the migratory path. Using 20 years of data on breeding phenology and success of 3 species of ducks differing in their migratory strategy - Teal Anas crecca, Mallard Anas platyrhynchos and Common Goldeneye Bucephala clangula - in a watershed in Finland, we test the idea that variation in spring phenology affects the reproductive performance of duck species differently depending on their migration pattern.




Esa Hohtola, Markku Orell, Kari Koivula, Jan-Âke Nilsson, Juli Broggi

Metabolic adaptation of the Great Tit (Parus major)

Department of Biology, University of Oulu.

A series of studies comparing the metabolic traits (especially basal metabolic rate, BMR) of the Great Tit (Parus major) between a northern (Oulu, Finland) and southern (Lund, Sweden) population was undertaken in 2003-2009. The main results were: 1) Birds from the more northern location had a higher (nocturnal) BMR and also had higher thermogulatory costs. 2) A common-garden experiment revealed a genetic difference between Oulun and Lund populations in the response of BMR to local conditions. 3) BMR was found to be a repeatable trait and repeated measurements of BMR showed that BMR declined with age. 4) The main proximate factors influencing BMR were (in addition to body mass) season, locality, date, and previous-week temperature. Additional experiments provided evidence that nocturnal hypothermia (shallow torpor) is an important energy-sparing adaptation in the great tit. The results show that BMR is a flexible trait and probably indicates overall work capacity. The cross-fostering experiment shows that local genetic adaptation of metabolic traits has occurred despite intensive gene flow from the more southern populations. The high repeatability of BMR suggests that it may be a heritable trait and thus a target of natural selection.




Sanna Aitto-oja, Petri Nummi

Timebudget of Common Cranes (Grus grus) vary in different habitats -implications for management

Department of Forest Sciences, University of Helsinki.

The increasing population of Common Cranes (Grus grus) are flocking to cultivated fields to forage after breeding time in autumn. This is important for successful migration. Human-crane conflicts can arise when cranes cause crop damages, and for management purposes it's important to prevent them. To minimize crop loss, the creation of artificial feeding fields has been suggested. Our study area is the most important staging area in Finland. We compared the time allocation in the most attractive habitats in this area, investigated if the pattern of daily group size corroborates the findings of earlier studies and discussed management implications. Cranes used the two top-rated habitats for clearly different purposes: barley for feeding and grass for resting. Group size increased daily from early morning towards the roost flight in evening. This can be a result of risk-sensitive behaviour and predator avoidance, although at present the predation risk in the area is low. Water availability was an important factor in crane habitat use. For successful creation of feeding fields, one needs to create habitats which fulfil the varying needs of cranes.




Aurélie Davranche, Céline Arzel, Hannu Pöysä, Petri Nummi, Johan Elmberg, Preben Clausen, Petri Pellikka, Gäetan Lefebvre & Brigitte Poulin

Space based tools to monitor the habitats of migratory waterbirds

Erlangen-Nürnberg University Institute of Geography, Germany.

Natural fluctuations in the availability of suitable habitat coupled with anthropogenic activities (hunting, agriculture, tourism, urbanism) and anticipated modifications due to climate change confront migratory waterbirds with a formidable challenge. Among them, dabbling ducks, greatly rely on local exogenous resources to fulfil their energy requirements. Habitat suitability along their flyway is of primary importance as any change might induce dramatic effects on individual survival and breeding success. Although, the monitoring of such sensitive flooded areas that are wetlands stopover sites is usually complex, space based techniques, with an exhaustive and systematic covering of the territory and a periodical data acquisition, can explore cost-efficiently the ecological conditions for migratory species in these environments. Hence, multiseason reflectance data from radiometrically and geometrically corrected multispectral SPOT-5 scenes, combined with thorough field campaigns and land cover digitizing using data mining, can provide robust tools for habitat monitoring and help the conservation of wetlands for migrants.




Pekka Rusanen, Timo Asanti, Markku Mikkola-Roos, Aleksi Lehikoinen

Population dynamics of the Great Cormorant in Finland

Finnish Environment Institute.

The Great Cormorant started to breed in Finland in 1996 after heavy increase and expansion of population in Western Europe. Since then the Finnish Environmental Institute has monitored the population development of cormorants with the help of volunteer ornithologists. The population has grown rapidly and the line of 10 000 breeding pairs was reached in 2008. This rapid population increase has been noted by the local inhabitants, the press and the policy makers, especially because of the possible conflict between cormorants and fishery. The species is widely despised and over half of the colonies have been disturbed illegally by humans despite the fact that nearly 70 % of the colonies are situated in protected areas. Nevertheless, persecution has hardly affected the population growth rate, which has been the highest in all European countries. This has been caused by heavy immigration from southern breeding areas. Our results show that winter climate affects the population growth rate: colder is the winter lower is the growth. The growth rate has been also decreasing during last ten years suggesting that population is on its way to saturate, which has occurred in many Western European countries before.




Jari Valkama, Pertti Saurola

Finnish Eagle Owls Bubo bubo are in danger - or are they?

Monitoring Team, Finnish Museum of Natural History, University of Helsinki.

In the 1960s, the size of the Finnish Eagle Owl population was 500-1,000 pairs. Since then, the number of Eagle Owls increased, and in the 1980s the population size was 2,500 pairs. The increase coincided with the following factors: (i) protection status of the species improved; (ii) the species learned to utilise dense Norway Rat Rattus norvegicus populations at improperly managed refuse dumps, and (iii) modern forestry has drastically increased the number of suitable nest sites (clearcuts). The owls showed an excellent ability to adapt to dumps, villages and cities. However, since early 1990s the population size has declined to only 1,200 pairs in 2008. The annual population change of the Eagle Owl for the period 1994-2008 has been 4.7 %, which suggests that the population size will halve during only less than 20 years. This reduction is most probably due to the fact that as much as 90 % of old refuse dumps have been closed during the last 20 years, which in turn means that Eagle Owls have lost access to easy food. These changes may have been critical for reproductive success and survival of young and breeding adults.




Mia Rönkä, Stefan Heinänen, Mikael von Numers

Modelling the occurrence and abundance of a colonial species, the Arctic Tern (Sterna paradisaea) on the Finnish coast

Department of Biology, University of Turku.

Knowledge of the habitat requirements and suitable breeding areas of sea birds is crucial for their management and conservation. However, there are still few studies that have modelled the breeding distribution and abundance of colonial sea birds. We created predictive distribution models for the Arctic Tern Sterna paradisaea, using 14 environmental variables calculated for 525 islands in the Archipelago Sea in SW Finland. We modelled the occurrence (presence/absence) using generalised additive models (GAMs) and abundance (colony size) using hurdle models fitted with GAM. The species seemed to prefer large and low islands with sparse vegetation, and large colonies were found on large and exposed islands with sparse vegetation. Large islands generally provide a more diverse environment than small islets. Sparse vegetation favours the Arctic Tern, as tree-covered islands are likely to host corvids that are important nest predators in the archipelago. Although the hurdle models did not produce accurate pair number estimates, they indicated which islands are suitable for larger colonies. Abundance is crucial for the breeding site selection and breeding success of colonial birds. This modelling technique can therefore be of great value for the conservation and management of the Arctic Tern and similar colonial species.




Veli-Matti Väänänen, Petri Nummi, Esa Pienmunne

Divers in national parks - management improve breeding success

Department Forest Sciences, University of Helsinki.

We studied breeding success of Red-throated Diver Gavia stellata and Black-throated Diver G. arctica during 1994-2010 in Nuuksio National Park, Southern Finland. Human actions, such as increasing recreational activity in lakes, have impaired the breeding areas of divers. We assumed that human actions have led to increased nest predation, and predicted that mitigation of human disturbance with management would lead to better brood production. We conducted an experiment using peat hummock to build floating nesting sites for G. stellata. We used G. arctica as control (no management). We found that the population of G. stellata increased steadily whereas G. arctica stayed relatively stable. G. stellata had three times higher breeding success than G. arctica (pairs with brood 71% vs. 24%, juveniles/pair 1.04 vs. 0.34, respectively). In addition, unlike in G. arctica, juveniles/pair -index of G. stellata did not decrease when the number of pairs increased. All nesting attempts of G. stellata failed in mainland shoreline mire margins, and also G. arctica nested successfully only in lakes with islands. Our results indicate that artificial nesting sites are a good solution to increase the breeding success of G. stellata.




Gaidis Grandāns, Keišs Oskars, Andris Avotinš

Sex and age structure of the Long-eared Owl (Asio otus) migration at Pape, Latvia

University of Daugavpils.

Data from Latvian Ringing centre about captured Long-eared Owls at Pape ornithological research centre (56°09' N, 21°03' E) in 1967-2009 are analyzed in this study. Totally 5964 Long-eared Owls were captured. Owl capture at Pape during autumn migration was conducted by Rybatschy type trap during the period of 1966-1992. Capture was continued 1992-2009 with smaller Helgoland-type trap. Most of Owls in 1992-2009 were captured by mist-nets. Number of migrating owls have peaks every 3rd - 5th year. Autumn migration of owls at Pape starts at the beginning of September and lasts until the end of November. Young birds dominated during migration (77.5%), but their proportion on average was lower (61.8%) in years when migration intensity was at its minimum. Differences in timing of migration between young and adult birds were observed. Young birds and females migrated earlier. Adult birds, especially adult males, migrated later.




Kārlis Millers

(European) Great Cormorant (Phalacrocorax carbo sinensis) diet in Latvia

Laboratory of ornithology, Institute of biology, University of Latvia.

The first research of Great Cormorant diet in Latvia was made on 2009 in four different lakes. The pellets were collected in costal lake Kanieris and three inland lakes - Razna, Ezezers and Rusons. Colonies were attended twice per breeding season. Research of cormorant diet continued also in 2010. According to the research made during 2009, totally 797 objects of 19 fish species were analyzed. Most common species was Bleak (Alburnus alburnus) (n = 227), Perch (Perca fluviatilis) (n = 133) and Eelpout (Zoarces viviparus) (n = 156). Medium length of fish was 17,4 cm. Longest - Eel (Anguilla anguilla) 62 cm. Shortest - Three-spined stickleback (Gasterosteus aculeatus) 4 cm. Heaviest - Tench (Tinca tinca) 629 g. Lightest - Three-spined stickleback 3 g. In general main part of cormorant diet consists of Tench - 34,43%. In Kanieris lake main part was Eelpout (37%), Razna - Perch (48,38%), and Tench in Ezezers (58,73%) and Rusons (34,50%). Estimated mass eaten by cormorants during the breeding season in researched colonies was ~ 50,7 t.




Olli Loukola

Intraspecific Learning In Nest-site Selection

Department of Biology, University of Oulu.

Recent studies indicate that many migratory birds use resident tits (Parus spp.) as tutors in important decisions. For example, some migrants are able to copy or reject selectively behavioural traits of tits associated with good and bad fitness correlates, respectively. We do not know, however, what is the role of social learning in the behaviour of tits. Here, we experimentally test whether tits, given a choice between two novel alternative behavioural traits of nest-site feature (two geometric symbols) choice, copy or reject the experimentally induced choice exhibited by simulated tit nests, when those nests portray high or low fitness (clutch size: 4 or 13 artificial eggs). The results suggest that neither the fitness correlate of the trait (clutch size), nor the female phenotype (age) affect the choices of the tits. Surprisingly, the age of the male strongly affected the choices. Adult males strongly copied the choices of conspecifics while juveniles rejected them. These results imply that male great tits may have stronger direct or indirect influence on the nest-site choice than is earlier thought. The effect of male age on copying and rejection behaviour is still speculative but dominance relationships or intraspecific competition are plausible explanations.




Mārcis Tīrums

The ornithophenological time series dependence of climate variables in Snepele (Latvia) from 1947-2007

University of Latvia.

This study is based on the first arrival dates of 77 bird species collected in the period of 1947-2007 for the area of Snēpele, Western Latvia. The aim of this study was to determine the change of the spring arrival of birds in relation to climatic factors. The data of first arrival of birds has been analyzed compare with mean air temperature, snow cover, precipitation and North Atlantic Oscillation index NAOi six month - December, January, February, March, April and May. To detect possible long- term trends in the timing of bird species and climatic variables Mann-Kendall Pirson correlation and the linear regression were used. Results show that 16 species have statistically significant trend toward earlier arrival. Since 1947 the short distance migrants have arrived approximately 2.2 days per decade ¯¹ earlier. The highest significant changes occurred in the arrival of the Common Crane Grus grus, Grey Heron Ardea cinerea, Whooper Swan Cygnus cygnus and Common Buzzard Buteo buteo. The arrival date of Common Crane Grus grus is becoming earlier on average at the rate of 6.2 days a decade ¯¹. Since 1989 the arrival trends of short distance migrants have revealed a slight trend toward later arrival.

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Abstracts of the presentations

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List of participants