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Abstract The protection of endangered species requires knowledge about the habitat requirements and the genetic issues related to the population viability. In this doctoral thesis, I defined the breeding habitat features of the Finnish populations of the Golden Eagle (Aquila chrysaetos) and the Peregrine Falcon (Falco peregrinus) by applying habitat suitability modelling. Secondly, I studied the conservation genetic issues of the Finnish population of the White-tailed Eagle (Haliaeetus albicilla) and the two Reed Bunting subspecies Emberiza schoeniclus witherbyi and E.s. lusitanica met in the Iberian Peninsula. All study populations are classified as threatened according to IUCN classification and they have experienced declines in population sizes in recent history. My results from habitat suitability models showed that human-induced changes in habitat threaten the Golden Eagle in Finland. The relative suitability for the species presence dropped to zero when the proportion of human altered landscape (agricultural or urbanized areas) in the core of the breeding habitat (4 km2) was more than 5%. Models further showed that habitat structure influences breeding habitat selection of the Peregrine Falcon, as it favours well-connected areas of open peatlands. Therefore, fragmentation (i.e., decreasing the connectivity) of open peatlands decreases the habitat quality for the species. The White-tailed Eagle has recovered mainly through local growth, but my results suggest that gene flow from neighbouring populations has had an impact as well, and has enhanced the genetic viability of the Finnish population. The current structure of the two subpopulations (one along the Baltic Sea coast line and another inland in Northern Finland) results mainly from the species’ ecology (i.e., philopatric behaviour), not from the recent population bottlenecks. The effective population size estimate of the coastal subpopulation of White-tailed Eagle was below the critical size needed to maintain evolutionary potential. The estimates of the effective population sizes for E.s. lusitanica and E.s. witherbyi and inland subpopulation of White-tailed Eagle were close or below the critical level of 50, which makes them prone to losing fitness due to inbreeding depression in the short term. Therefore, these study populations need to increase in size in order to secure population viability in the future. / Tiivistelmä Ihmisen aiheuttamat elinympäristöjen muutokset uhkaavat biodiversiteettiä kasvattamalla yhä useampien eliölajien sukupuuttoriskiä. Tehokkaat suojelutoimenpiteet edellyttävät tietoa uhanalaisten lajien elinympäristövaatimuksista sekä populaation elinkyvylle keskeisistä geneettisistä tekijöistä. Tarkastelen väitöskirjatyössäni maakotkan (Aquila chrysaetos) sekä muuttohaukan (Falco peregrinus) Suomen populaatioiden pesimäympäristön piirteitä maisemaekologisen mallinnuksen avulla. Toiseksi tarkastelen Suomen merikotkapopulaation (Haliaeetus albicilla) sekä Iberian niemimaalla esiintyvien pajusirkun alalajien Emberiza schoeniclus witherbyin ja E.s. lusitanican suojelun kannalta tärkeitä geneettisiä tekijöitä. Kaikki tutkimuspopulaatiot ovat uhanalaisia ja ne ovat kärsineet voimakkaista kannan pienenemisistä. Maisemaekologiset mallit osoittivat maakotkan välttävän ihmisen muokkaamaa ympäristöä (maatalousalueet ja rakennetut alueet). Lajin esiintymistodennäköisyys laski nopeasti nollaan, kun ihmisen muokkaaman ympäristön osuus nousi yli 5 prosenttiin pesimäympäristön ydinalueella (4 km2). Mallit osoittivat maiseman rakenteen vaikuttavan muuttohaukan habitaatinvalintaan, sillä se suosi pesimäympäristönään kytkeytyneitä avosoita. Avosoiden pirstoutuminen (l. kytkeytyneisyyden väheneminen) vähentää näin ollen muuttohaukan pesimäympäristön laatua. Merikotkapopulaatio on toipunut pääosin paikallisen kasvun myötä, mutta tulokseni viittaavat myös siihen, että geenivirta naapurimaiden populaatioista on lisännyt Suomen populaation geneettistä muuntelua. Nykyinen rakenne (rannikon ja Lapin alapopulaatiot) on seurausta lajin synnyinpaikkauskollisuudesta, ei niinkään populaatiokoon romahduksista. Rannikon merikotkapopulaation efektiivinen koko jäi alle kriittisen rajan, joka tarvitaan evolutiivisen potentiaalin säilymiselle. Pajusirkun alalajien sekä Lapin merikotkapopulaation efektiiviset populaatiokoot olivat lähellä kriittisenä pidettyä 50:tä tai jäivät alle, joten ne ovat vaarassa menettää kelpoisuutta sukusiitosdepression seurauksena lyhyellä aikavälillä. Sekä pajusirkun alalajien että merikotkapopulaatioiden tulee sen vuoksi kasvaa säilyäkseen elinvoimaisina tulevaisuudessa.

Sexual selection theory tries to explain evolution of apparently useless traits which mainly developed in males of numerous species. One such trait is also rich and vibrant coloration, typical for many of the bird species. These traits are difficult to be falsified, and therefore they honestly signal quality of the individual. Carotenoid coloration reflects the health condition and melanin coloration the social status, even though this traditional division might not be as strict according to the latest studies. Apart from these ways of maintaining honesty, recent studies are focusing more also on the effect of hormones, mainly two steroids: male sexual hormone - testosterone -, and the "stress" hormone - corticosterone. Both hormones could positively influence male's sexual traits such as ornamental coloration. On the other hand, elevated levels of these hormones possess risk to the organism (higher energetic expenditure, chronic stress), therefore also might potentially become costly. Using photographs of birds in standardized conditions as well as spectrophotometry I analyzed the plumage coloration of males of the Yellowhammer (Emberiza citrinella). Concentrations of testosterone and corticosterone deposited in feathers were analyzed using the LC-MS/MS. Also, for males in breeding season 2015,...

Information on habitat preferences is critical for the successful conservation of endangered species. For many species, especially those living in remote areas, we currently lack this information. Time and financial resources to analyze habitat use are limited. We aimed to develop a method to describe habitat preferences based on a combination of bird surveys with remotely sensed fine-scale land cover maps. We created a blended multiband remote sensing product from SPOT 6 and Landsat 8 data with a high spatial resolution. We surveyed populations of three bird species (Yellow-breasted Bunting Emberiza aureola, Ochre-rumped Bunting Emberiza yessoensis, and Black-faced Bunting Emberiza spodocephala) at a study site in the Russian Far East using hierarchical distance sampling, a survey method that allows to correct for varying detection probability. Combining the bird survey data and land cover variables from the remote sensing product allowed us to model population density as a function of environmental variables. We found that even small-scale land cover characteristics were predictable using remote sensing data with sufficient accuracy. The overall classification accuracy with pansharpened SPOT 6 data alone amounted to 71.3%. Higher accuracies were reached via the additional integration of SWIR bands (overall accuracy = 73.21%), especially for complex small-scale land cover types such as shrubby areas. This helped to reach a high accuracy in the habitat models. Abundances of the three studied bird species were closely linked to the proportion of wetland, willow shrubs, and habitat heterogeneity. Habitat requirements and population sizes of species of interest are valuable information for stakeholders and decision-makers to maximize the potential success of habitat management measures.

The inter-population geographic song variability can be found in many bird species. One of the most interesting types are dialects, characterized by sharp boundaries between populations of individuals sharing the same particular song type. Despite many years of investigation there is no satisfactory answer to the question how these borders persist over the years at nearly same sites. Distinctions between dialects allow recognition of males from different populations and could influence the territorial behaviour. Various habitats, however, degrade the sound differently; it is therefore possible that specific habitats are preferred by individuals with specific dialects. Both social interactions and acoustic properties of the locality could also be only secondary factors and the dialect distribution could be the result of the habitat distribution either in present or in recent past. In this diploma thesis, several hypotheses were tested on the example of Yellowhammer (Emberiza citrinella) - a songbird abundant in open land with simple song and easily recognizable dialects. The thorough data concerning the habitats and dialect distribution were obtained at the dialect borders at two localities in Czech Republic. The reactions of territorial males to both foreign and their own dialects were also...

The Ortolan Bunting (Emberiza hortulana) is a farmland bird species, whose population size has declined very sharply in recent decades, especia ll y in Western and Central European countries. The aim of our study in 2015 was to record where the last populations of this critically endangered species in the Czech Republic are located and also what habitat the species associated with. We examined nine areas (925 km2 in total). Two main areas of occurrence (surface mines in northern Bohemia and farmland landscape of Silesia) and two small isolated populations in central Bohemia were registered for this species. In contrast, observations in some traditional areas of its occurence (České středohoří in northern Bohemia, Hovorany-Čejkovice region in southe r n Moravia and Javoricko region in Silesia) were negative. Altogether, we counted 75-79 singing males. Our estimation of the size of the Czech population in 2015 is 75-100 singing males, which indicates further population decline compared to the last mapping in 2001-2003. Furthermore, habitat associat io ns were investigated at two spatial scales and we made habitat compar is o n between farmland and post-mining landscape. Our research highlights a high degree of flexibility in habitat selection of Ortolan Bunting and also positive association with high...

A playback experiment in which a recording of vocalization is played to the tested subject and its response is observed, is a widely used tool for examining bird song and its functions. Most often only acoustic stimulus is used, but sometimes a visual stimulus is also provided in the form of a dummy. Taxidermic mounts or models made from different materials are used as the dummy. It is discussed among researchers, whether it is or is not necessary to use a dummy in experiments and how does its presence affect behavior of the tested individuals. However, only few studies directly focus on this issue and test the effect of dummies. The best way to test the effects of a dummy on passerines in playback experiments is to test the same individuals in both situations (with a dummy and without a dummy) and compare the reactions. The aim of this theses was to perform such experiments on Chiffchaff (Phylloscopus collybita) and Yellowhammer (Emberiza citrinella) males and to find out whether they would behave similarly in both variants of the experiment, or if their reaction would be enhanced in the presence of a dummy. Chiffchaffs reacted significantly more aggressively in the dummy experiment. The biggest difference was time spent by attacking the dummy and staying close to it. In Yellowhammers, the dummy...