White-tailed Eagle Haliaeetus Albicilla Research Articles

Numbers of wintering waterbirds in the Czech Republic: long-term and spatial-scale approaches to assess population size

Capsule Two nationwide monitoring schemes, the International Waterbird Census (IWC) and Atlas of Wintering Birds (AWB), provide comparable estimates of national population sizes of wintering waterbirds. Differences between these estimates for several species can be explained by differences in their migratory strategy.Aims We tested whether species-specific variables, i.e. the total numbers, distribution and migration strategy affected the accuracy of wintering population estimates provided by two different monitoring schemes, the IWC and AWB.Methods Estimates of the numbers of 81 waterbird species are compared, using data from IWC (mid-January) and AWB (December, January and February) in the Czech Republic between 1982 and 1985. Log-linear Poisson regression analysis was used to estimate missing IWC data from long-term IWC data series (1966–2013) using Trends and Indices for Monitoring data software. A series of generalized linear models was estimated to analyse the effect of species-specific variables on the presence of overlap between IWC and AWB national population estimates.Results The range of numbers recorded by IWC data overlap the range of AWB numbers in 22 of the 53 investigated species recorded by both monitoring schemes. Numbers of most other species based on the IWC counts were lower when compared with those generated from AWB data and included several widespread species, e.g. White-tailed Eagle Haliaeetus albicilla and White-throated Dipper Cinclus cinclus. In contrast, population size estimates based on IWC counts were higher than those generated from AWB estimates for one species, the Ferruginous Duck Aythya nyroca. The differences between IWC and AWB estimates were significantly higher in late-departing and early-arriving migrants. There was no effect of species distribution and population size.Conclusions Based on a single-country data sample, we support the relevance of the IWC Census methodology to produce estimates of wintering waterbird numbers and to calculate 1% thresholds for waterbird species, which we use to indicate nationally important wetland sites for future conservation and protection in the Czech Republic.

Brominated and phosphorus flame retardants in White-tailed Eagle Haliaeetus albicilla nestlings: Bioaccumulation and associations with dietary proxies (δ13C, δ15N and δ34S)

Very little is known on the exposure of high trophic level species to current-use brominated (BFRs) and phosphorus flame retardants (PFRs), although observations on their persistence, bioaccumulation potential, and toxicity have been made. We investigated the accumulation of BFRs and PFRs, and their associations with dietary proxies (δ13C, δ15N and δ34S), in plasma and feathers of White-tailed Eagle Haliaeetus albicilla nestlings from Trøndelag, Norway. In addition to accumulation of a wide range of polybrominated diphenyl ether (PBDE) congeners in both plasma and feathers, all non-PBDE BFRs and PFRs could be measured in feathers, while in plasma only two of six PFRs, i.e. tris-(2-chloroisopropyl) phosphate (TCIPP) and tris-(2,3-dichloropropyl) phosphate (TDCPP) were detected. PFR concentrations in feathers (0.95–3000ngg−1) were much higher than selected organochlorines (OCs), such as polychlorinated biphenyl 153 (CB 153; 2.3–15ngg−1) and dichlorodiphenyldichloroethylene (p,p′-DDE; 2.3–21ngg−1), PBDEs (0.03–2.3ngg−1) and non-PBDE BFRs (0.03–1.5ngg−1). Non-significant associations of PFR concentrations in feathers with those in plasma (P≥0.74), and their similarity to reported atmospheric PFR concentrations, may suggest atmospheric PFR deposition on feathers. Most OCs and PBDEs, as well as tris(chloroethyl) phosphate (TCEP), tris(phenyl) phosphate (TPHP) and tri-(2-butoxyethyl) phosphate (TBOEP) were associated to δ15N and/or δ13C (all P≤0.02). Besides δ15N enrichment, δ34S was depleted in nestlings from fjords, inherently close to an urbanised centre. As such, both may have been a spatial proxy for anthropogenic disturbance, possible confounding their use as dietary proxy.

Antiparasite treatments reduce humoral immunity and impact oxidative status in raptor nestlings

Parasites are natural stressors that may have multiple negative effects on their host as they usurp energy and nutrients and may lead to costly immune responses that may cause oxidative stress. At early stages, animals may be more sensitive to infectious organisms because of their rapid growth and partly immature immune system. The objective of this study was to explore effects of parasites by treating chicks of two raptor species (northern goshawk Accipiter gentilis and white-tailed sea eagle Haliaeetus albicilla) against both endoparasites (internal parasites) and ectoparasites (external parasites). Nests were either treated against ectoparasites by spraying with pyrethrin or left unsprayed as control nests. Within each nest, chicks were randomly orally treated with either an antihelminthic medication (fenbendazole) or sterile water as control treatment. We investigated treatment effects on plasma (1) total antioxidant capacity TAC (an index of nonenzymatic circulating antioxidant defenses), (2) total oxidant status TOS (a measure of plasmatic oxidants), and (3) immunoglobulin levels (a measure of humoral immune function). Treatment against ectoparasites led to a reduction in circulating immunoglobulin plasma levels in male chicks. TOS was higher when not receiving any parasite reduction treatment and when receiving both endo- and ectoparasitic reduction treatment compared with receiving only one treatment. TAC was higher in all treatment groups, when compared to controls. Despite the relatively low sample size, this experimental study suggests complex but similar relationships between treatment groups and oxidative status and immunoglobulin levels in two raptor species.

Returning white-tailed eagles breed as successfully in landscapes under intensive forestry regimes as in protected areas

Given the unprecedented biodiversity crisis and scarcity of conservation resources, each single conservation effort must be allocated cost-effectively. Therefore, there is a growing need to evaluate the effectiveness of such efforts, particularly in the case of large and charismatic predators that have attracted a large share of species conservation funding. In Finland, conservation interventions aimed at protecting nest sites of the white-tailed eagle Haliaeetus albicilla were initiated based on general concerns of increasing disturbance posed by human encroachment and forestry practices. We evaluated the current effectiveness of this conservation program. We found that neither nest occupancy nor breeding success of white-tailed eagles were affected by the protection status of the land in which the nest was located (protected areas or unprotected land), or by the size of the area under protection. In addition, the type of forest management at the nest site or the presence and vicinity of anthropogenic infrastructures (roads and buildings) did not have any apparent effect on nesting eagles. Our results are encouraging, as they show that the white-tailed eagle breeds successfully in landscapes under intensive forestry, and thus the future of the species appears not to be threatened by forest management. Our results furthermore allow updating the allocation of resources for nature conservation in Finland, potentially by prioritizing more cost-effective conservation programs on other species and ecosystems.

An overview of monitoring for raptors in Finland

Abstract In Finland, population monitoring for both diurnal and nocturnal raptors has been almost entirely based on fieldwork carried out by voluntary raptor ringers. Responsible organisations include the Finnish Museum of Natural History, with economic support for administration from the Ministry of Environment, “Metsahallitus” (former National Board of Forestry) and WWF Finland. Since the early 1970s, numbers and productivity of four endangered species, the White-tailed Eagle Haliaeetus albicilla, Golden Eagle Aquila chrysaetos, Osprey Pandion haliaetus and Peregrine Falcon Falco peregrinus have been monitored by country-wide Comprehensive Surveys, with the aim of checking all known nest sites of these species every year. The Gyrfalcon F. rusticolus was included in this group in the late 1990s. Data for monitoring the populations of the other raptor species have been gathered by the Raptor Grid and Raptor Questionnaire projects. The Raptor Grid project produces annual population indices, which are calculated from the data collected from 10 × 10 km study plots (n = ca. 130/year) and quite well reflect the annual population fluctuations and longterm trends of seven common species of diurnal and six species of nocturnal raptors breeding in the southern part of Finland. For the rest of the species, which are either rare all over Finland or breed mostly in the north, outside the good coverage of the distribution of Raptor Grid study plots, conclusions on population changes are based on the total numbers of occupied territories and active nests reported annually by the Raptor Questionnaires

An overview of monitoring for raptors in Bulgaria

Abstract Since 1990, nature conservation NGOs are the main players in the running of nation-wide research and monitoring schemes for raptors in Bulgaria. Among them, the Bulgarian Society for the Protection of Birds (BSPB) and Green Balkans are most active, covering the most threatened diurnal raptors in the country. The key species covered by comprehensive monitoring schemes are the Imperial Eagle Aquila heliaca, White-tailed Eagle Haliaeetus albicilla, Egyptian Vulture Neophron percnopterus, Griffon Vulture Gyps fulvus, Black Vulture Aegypius monachus, Saker Falcon Falco cherrug and Red-footed Falcon F. vespertinus. Information on their distribution, numbers, breeding success, productivity, diet, movements etc. is gathered on annual basis. The Buzzard Buteo buteo and Kestrel F. tinnunculus are also regularly monitored at the national level by the Common Bird Monitoring scheme. Distribution of all raptor species has been studied for the purpose of the Atlas of Breeding Birds in Bulgaria. The contemporary satellite telemetry methods revealed important aspects of movements and threats to eagles and vultures from Bulgaria within the country and abroad. Main threats for the raptors in Bulgaria are related to habitat loss, unnatural mortality and disturbance. The main gaps in raptor monitoring in Bulgaria are related to the lack of coverage of most of the diurnal species and owls. There is a strong national and international cooperation in conjunction with the work concerning Imperial Eagle, Egyptian and Griffon Vultures. However, further enhancement of cooperation on other raptor species and issues such as lobbying for implementation of raptor-friendly agricultural practices and enhancement of various economic sectors are needed

First documented nesting by White-tailed Sea Eagles (Haliaeetus albicilla) in Eastern Slovakia

Abstract The 1980’s and 90’s saw growth in the population and expansion of the areas occupied by White-tailed Sea Eagles over the whole territory of their occurrence in Europe. Under this influence the number of these eagles observed during the nesting period also increased in Eastern Slovakia. The most frequent occurrences have been recorded in the wetland woods along the River Latorica on the East Slovakian Plain, but so far without any documented nesting. In 2002 one pair built a nest in the Vihorlat Hills near Zemplínska šírava reservoir, but they did not actually nest in it either that or the following year. Breeding by these eagles in these hills was noted over 70 years ago by Hrabar (1932) and Molnár (1933), but no nesting was documented. Nesting was documented for the first time in 2004, when one pair successfully raised two offspring. This pair successfully bred in the same nest in 2005 and 2006 too.

Molecular identification of traces from the White-tailed Sea Eagle

Over the preceeding decades, after periods of dramatic decline and extinction in many parts of Europe, the White-tailed Sea Eagle (Haliaeetus albicilla) has re-colonized traditional breeding areas. However, this large apex predator remains threatened, not only by the bioaccumulation of environmental pollutants, but also by targeted poisoning and poaching. In connection with a forensic case, a novel PCR assay was developed for the sensitive and specific detection of sea eagle DNA traces in questioned samples of unknown origin. The assay amplifies a fragment of the popular phylogenetic marker gene cytochrome b. Primers were designed to bind sites with relatively high variability between homologous sequences from H. albicilla and other related European birds of prey. Assay sensitivity was sufficient for single cell analysis. Specificity was tested in vitro and the primers did not cross-detect DNA from humans, chicken and the following raptors: Common Buzzard (Buteo buteo), Northern Goshawk (Accipiter gentilis), Red Kite (Milvus milvus) and Black Kite (Milvus migrans). Applicability for the analysis of poor quality samples was demonstrated with extracts from field-collected small molted down feathers that did not contain detectable amounts of sea eagle nuclear DNA. Amplicons of the expected size were generated, purified and sequenced. Sequence data were subjected to Basic Local Alignment Search Tool analysis and affiliated with cytochrome b from H. albicilla. The novel PCR primers allowed for the correct assignment of traces from H. albicilla, even in mixed samples and in cases with limited and degraded biological material.

The history of eagles in Britain and Ireland: an ecological review of placename and documentary evidence from the last 1500 years

Capsule The loss of eagles from large tracts of lowland and upland habitat in Britain and Ireland over the last 1500 years is attributed to human activity. Aim To estimate changes in past distribution and population size of Britain and Ireland's two native eagle species. Methods Placenames suggesting the past presence of eagles were categorized according to modern knowledge of the species' ecology. Together with documented historical locations, these sites were mapped to derive approximate former ranges. Population estimates were made for each species at about 500 and 1800 CE. Results Estimated range at about 500 CE was 110 250 km2 for White-tailed Eagles Haliaeetus albicilla and 98 500 km2 for Golden Eagles Aquila chrysaetos, with 44 600 km2 of overlap. Population sizes were 800–1400 pairs of White-tailed Eagles and 1000–1500 pairs of Golden Eagles, declining to 150 and 300–500 pairs, respectively, by 1800. Conclusion Our results provide evidence for the presence within the last 1500 years of one or other species of eagle throughout much of Britain and Ireland. The influence of climate change on eagle habitat has been subsumed by the effects of habitat destruction and persecution as primary causes of absence from much of their former range.

Plasma concentration of α-tocopherol in different free-ranging birds of prey

In this study, we investigated the α-tocopherol plasma concentrations in healthy free-ranging nestlings of the white-tailed sea eagle (Haliaeetus albicilla) (n = 32), osprey (Pandion haliaetus) (n = 39), northern goshawk (Accipiter gentilis) (n = 25), common buzzard (Buteo buteo) (n = 31), and honey buzzard (Pernis apivorus) (n = 18) as well as of free-ranging adults of the white-tailed sea eagle (n = 10), osprey (n = 31), and northern goshawk (n = 45). α-Tocopherol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. α-Tocopherol plasma concentrations in nestlings of osprey, white-tailed sea eagle, and northern goshawk did not differ significantly amongst the species, but the common buzzard and honey buzzard nestlings had significantly lower α-tocopherol plasma concentrations than nestlings of the other species (both P < 0.001). Adult male ospreys and white-tailed sea eagles had significantly higher α-tocopherol concentrations compared to adult females (both P < 0.005). Adult ospreys and northern goshawks had significantly higher α-tocopherol plasma concentrations compared to their nestlings (both P < 0.001). In adult female northern goshawks, plasma concentrations of α-tocopherol increased significantly before egg laying (P < 0.001). These results demonstrate α-tocopherol plasma concentrations in birds of prey to be species specific and influenced by age and reproductive status.

Mike Madders

Mike Madders was a professional ornithologist and ecologist, best known for his research in Scotland on Hen Harriers Circus cyaneus, his work on the impact of wind power development on upland birds and for the popular books on birds that he both wrote and published. Mike started his work on birds in 1978, voluntarily monitoring Peregrine Falcons Falco peregrinus and Golden Eagles Aquila chrysaetos in Cumbria and guarding them against thieves. By day, he worked as a postmaster, the youngest in Britain at the time. While in Cumbria, Mike set up a popular Young Ornithologists’ Club group and wrote Bird Watching in the Lake District (1985). In 1984, Mike was employed by the RSPB to provide security for a White-tailed Eagle Haliaeetus albicilla nest on Mull, the result of releases on Rum. In 1985, the birds produced the first wild eagle chick born in Scotland in 70 years, the beginning of a still unfolding wildlife success story. The event was marked by Mike’s radio communication to his fellow eagle watcher: ‘I think we’re both daddies!’. In Scotland he continued to write and publish (through Saker Press) popular books on birds: Birds of Mull, Birds of Arran and Birdwatching in the Outer Hebrides. Birds of Mid-Argyll and Where to Watch Birds in Scotland were co-authored with Julia Welstead. All were illustrated by Philip Snow. While on Mull, Mike undertook RSPB and NCC seasonal contracts counting geese and monitoring raptors and other birds, and came to be seen as the RSPB presence there. In the winter, he gave evening classes and talks on birds and wildlife, and travelled widely. One tour of the US was at least part funded or facilitated by the bird talks he gave along the way. He moved to Islay in 1991. Mike did not have an undergraduate degree, but in 1991 he undertook a PhD course at Glasgow University. Contemporaries at Glasgow noted that at 2 m tall he was well built for the field work, which involved studying Hen Harriers in forestry plantations. He received his PhD in 1997, entitled ‘The effects of forestry on Hen Harriers Circus cyaneus’. From 1998 to 2002, Mike studied eagle predation of lambs on Mull with Mick Marquiss, finding that although some lambs were killed, most were scavenged. These findings, which endorsed some of the claims of local shepherds, eased a highly polarized situation and led to the ‘Natural Care’ package aimed at rewarding shepherds for looking after the interests of wildlife and improving lamb care. The timing of this coincided with the growth in eagle tourism to the island. In the mid 1990s, Mike started environmental consultancy and worked on some of the first wind power developments in Scotland. As a consultant, Mike was appreciated by clients for the quality of his work, and by the regulatory agencies and conservation bodies for his field experience, commitment to conservation, sharp and pragmatic mind, honesty and appreciation for commerce. In 1999, Mike and I established Natural Research, a registered charity in Scotland, whose mission is to provide high-quality wildlife research. Natural Research Projects (NRP), a commercial environmental consultancy, was set up as a subsidiary and profits from NRP were given to the charity to pursue its mission. Mike gained satisfaction from doing and supporting high-quality work in the commercial and charitable sectors, and was pleased by the commercial success of NRP. Mike helped devise many of the techniques currently used to measure bird responses to windfarm development, some now adopted as best practice in the UK and abroad. He provided training in these techniques to statutory agencies and to other environmental assessment professionals. He was sometimes brought in as an expert witness at public enquiries related to wind energy, both by developers and by Scottish Natural Heritage. Mike was the local representative for the British Trust for Ornithology (1988–99), a long-standing member of the Scottish Ornithologists’ Club, a member of the Institute of Biology and the Raptor Research Foundation, and a long-time member of the Argyll Bird Club. He was a member of the Scottish Raptor Study Groups, and chairman of the Argyll Raptor Study Group for a time. Mike was born in Leicester on 12 July 1957 and died with his son, Daniel, on 23 August 2009 in a canoeing accident on Loch Maree, Wester Ross. He will be remembered by his many friends, who found him sharp, humorous and honest. He is survived by the three sons he had with his former partner, Julia Welstead, and by his partner, Christine Cain.

Zero Prevalence of Influenza A Virus in Two Raptor Species by Standard Screening

Disease can have severe impact on animal populations, especially in rare species. Baseline data for atypical host species are missing for a range of infectious diseases, although such hosts are potentially more affected than the normal vectors and reservoir species. If highly pathogenic avian influenza strikes rare birds of prey, this may have crucial impact on the predator species itself, but also on the food web in which it interacts. Here we present the first large-scale screening of raptors that regularly consume birds belonging to the natural reservoir of influenza A viruses. Influenza A virus prevalence was studied in two rare raptors, the white-tailed sea eagle (Haliaeetus albicilla) and the peregrine falcon (Falco peregrinus). Nestlings were screened for active (181 white-tailed sea eagles and 168 peregrine falcons) and past (123 white-tailed sea eagles and 6 peregrine falcons) infection in 2006-2007, and an additional 20 succumbed adult white-tailed sea eagles were sampled in 2003-2006. Neither high- nor low-pathogenic influenza infections were found in our sample, but this does not rule out that the former may have major impact on rare raptors and their food webs.

Restoration of sea eagle population: A review

Abstract The population density of the white-tailed sea eagle Haliaeetus albicilla is very low in many countries. In last twenty years, the sea eagle population in South Bohemia was restored by strict protection subsidized by reintroduction. The active help consisted of feeding during winter and building of artificial nests. A new sea eagle breeding population arose in the Třeboň basin area in the early 1980’s. Until this time sea eagles had used former breeding places only for wintering, probably coming from the Baltic. The South Bohemian sea eagle population is very unique: it exists in a densely man-occupied landscape, mainly in areas with very intensive carp breeding in artificial fishponds and was partly artficially (help to wintering birds and reintroduction of some individuals) restored. The experience from South Bohemia may have importance for populations of the sea eagle in other areas of its occurence, primarily in the continental conditions

Population size, distribution and habitat selection of the white-tailed eagle Haliaeetus albicilla in the alluvial wetlands of Croatia

AbstractFrom 2003–2006, research on the breeding distribution of the white-tailed eagle (Haliaeetus albicilla) was conducted in Croatia in order to assess the size of the national population. In 125 locations, clear signs of breeding activity were found. An additional 10 presumably active territories were detected but it was not possible to locate the exact position of the nests and confirm the breeding. Based on this, it is concluded that the national breeding population is not less than 135 breeding pairs. The present distribution can be compared with previous reports with the exception of the area along the Ilova and Lonja rivers that have never been reported as an important breeding site. Analysis of the characteristics of 138 nest positions as well as preferences/avoidance of specific structural features were performed. The results showed that white-tailed eagles prefer to build their nests on pedunculate oaks, narrow-leafed ash and white poplars with the greatest preference for mature trees with a diameter above 92.5 cm. The minimal distance between two active pairs was 348 meters. More than 50% of the national population breed less than two km from a large water area and 95% of the population less than four km. More than 95% of the population breed at altitudes lower than 140 m above sea level and are further than one km away from the nearest human settlement, regardless of the availability of forests. According to several parameters (distance to a large water area, elevation, forest presence, distance to the nearest settlement, distance to highways and railways) geographic information system (GIS) helped to determine potential white-tailed eagle breeding areas.

Using Raptors as Environmental Sentinels: Monitoring the White-tailed Sea Eagle Haliaeetus albicilla in Sweden

This paper summarizes results from the monitoring of reproduction of white-tailed sea eagle in Sweden 1965-2006. Since 1989 the eagle population on the Swedish Baltic coast has been included in the National Environment Monitoring Program as an indicator species for potentially harmful chemicals. The percentage of successfully reproducing pairs and nestling brood size decreased in synchrony with rising concentrations of contaminants in the 1950s on into the 1970s. Mean productivity was 1.3 young per pair prior to 1950 and decreased to 0.3 in 1965-1985. Dichlorodiphenyldichloroethene (DDE) in eagle eggs decreased from a range of annual means in 1965-1974 of 600-1200 microg g(-1) (lipid weight) to 60-140 microg g(-1) in 1996-2005. Total polychlorinated biphenyl (PCB) concentrations averaged above 1000 microg g(-1) into the early 1980s and remained in the range of 250-500 microg g(-1) in 1996-2005. Productivity began to improve when concentrations of DDE and PCBs dropped below approximately 300 and 800 microg g(-1), respectively. Brood size remains below the pre-1950 level in one coastal region, indicating a possible impact from other contaminants. The power to detect significant trends under the program is presented and discussed: if white-tailed sea eagle reproduction had been monitored earlier during the 20th century, the negative impact of dichlorodiphenyltrichloroethane (DDT, source of DDE) would have been signaled as early as the 1950s in the Baltic Sea. The dramatic fall of white-tailed sea eagle reproduction under the influence of DDT and PCBs, and the subsequent rise following their ban, illustrates the usefulness of raptors like sea eagles as sentinels for environmental pollutants.

Morphological and genetic sex identification of white-tailed eagle Haliaeetus albicilla nestlings

Identifying the sex of bird nestlings is relevant to studies of behaviour and ecology and is often a central issue in the management of endangered or captive populations. The white-tailed eagle Haliaeetus albicilla is a formerly threatened Eurasian raptor which is closely monitored in many countries due to its high exposure to environmental pollutants in the food chain. The aim of this study was to evaluate the reliability of sex identification methods for white-tailed eagle nestlings based on morphological measurements that can be recorded at the nest by a single person and with minimum disturbance. The sex of each bird was independently determined using molecular (genetic) methods. One measure of tarsus width allowed the correct identification of sex for 96% of the nestlings from southern and central Sweden. However, we found that the criteria for sex identification were not directly applicable to the population in Swedish Lapland, where nestlings are typically thinner, probably due to a limited food supply. These results show that sexing in the field of white-tailed eagle nestlings can be feasible with high accuracy based on a limited number of measurements. However, the criteria employed to separate sexes may have to be adjusted for each population.

Specific status and pathogenicity of syngamid nematodes in bird species (Ciconiformes, Falconiformes, Gruiformes) from Germany

A total of 549 birds from four orders were examined for nematodes in their respiratory system from 1995 to 2000. Twelve individuals of Falconiformes (n = 503), one of Gruiformes (n = 22) and one of Ciconiformes (n = 1), but no bird of the order Strigiformes (n = 23) were infected with syngamids. The syngamid species included Hovorkonema variegatum, Syngamus trachea and Cyathostoma trifurcatum from the trachea, bronchi and air sacs, with H. variegatum being the most prevalent. Cyathostoma trifurcatum from a black stork Ciconia nigra is a new record for Germany. The marsh harrier Circus aeruginosus and the white-tailed sea eagle Haliaeetus albicilla are new hosts for H. variegatum. Morphological characters such as the dorsal rays of the bursa copulatrix, length of the spicules and the mouth capsule are used to differentiate species of the family Syngamidae. Egg size is different between S. trachea and H. variegatum. In addition to morphological characters, the nucleotide sequence of the SSU ribosomal gene was determined for H. variegatum. Pairwise comparisons with the SSU sequence of S. trachea (AF036606) revealed sequence difference of 2.6%. The nucleotide sequence of the second internal transcribed spacer of ribosomal DNA for different populations of H. variegatum was also determined. Pairwise comparisons revealed two separate strains with a sequence difference of 14.0% to 14.5% suggesting the existence of a cryptic species. Pathological findings associated with H. variegatum were found in 7 of 12 cases and consisted of thickened air sac walls and lesions or granuloma at the site of attachment of the worm, which occasionally involved the underlaying tissues. Lymphoplasmocytic air sacculitis was the most prominent histological lesion found.

Contribution to studies on white-tailed eagle (Haliaeetus albicilla Linnaeus, 1758) in Western Serbia and the Republic of Srpska

birds of prey in Europe. The nesting population of white-tailed eagle in Europe is estimated to number approximately 5000 pairs; approximately 1% of the entire European population nest in Serbia (BirdLife International, 2004). In the Pannonian lowland, this species was common in the 19th century (D o m b r o v s k i, 1895). Through destruction of habitats, drying of swamps, and cutting down of gallery forests on floodplains, the population density of white-tailed eagle decreased to only 10 pairs in the 70s of the last century (H a m, 1977). The whitetailed eagle is currently included in the IUCN list as a near threatened (NT) species (IUCN, 2006) susceptible to changes and disturbances in both terrestrial and aquatic habitats. This feature makes the white-tailed eagle an indicator species suitable for detection of disturbances and pollution, especially in aquatic habitats (H a m et al., 1988). CONTRIBUTION TO STUDIES ON WHITE-TAILED EAGLE (HALIAEETUS ALBICILLA LINNAEUS, 1758) IN WESTERN SERBIA AND THE REPUBLIC OF SRPSKA. S. Skoric1, Katarina Stefanovic2, and S. Marinkovic3. 1Center for Multidisciplinary Studies, University of Belgrade, 11000 Belgrade, Serbia; 2Birds of Prey Protection Fund, 11060 Belgrade, Serbia; 3Sinisa Stankovic Institute for Biological Research, 11060 Belgrade, Serbia

Fugler i Norge 2001 – Rapport fra Norsk faunakomité for fugl (NFKF)

THE NORWEGIAN BIRD REPORT 2001 - a report on locally uncommon and scarce birds in Norway in 2001, by the Norwegian Birds Records Committee (NFKF) The basis of this report is the annual reports produced by the county rarities committees. For 2001 all the counties contributed to the report, although the Svalbard archipelago and Jan Mayen as well as Finnmark, Troms and Sogn &amp; Fjordane countiesdid not produce own county reports. With the exception of the northernmost counties the report thus reflects fairly well observations from Norway in 2001. Readers should take care to note the geographical or time delimitation of the records stated for the different species, as stated in codes immediately after the scientific name of the species. The Norwegian Birds Records Committee (NFKF) has been publishing annual reports since 1991. Bewick&rsquo;s Swan Cygnus columbianus numbers were the lowest since 1991, and also the occurrence of Lesser White-fronted Geese Anser erythropus at the traditional feeding and roosting site Valdakmyra, Porsanger (FI) were particularly scarce this spring (lowest since 1993). However, this could partly be explained by early arrival at the breeding sites due to unusually early snow melting. Gadwalls Anas strepera have occurred in steadily increasing numbers in Norway in recent years, and 2001 was the best year to date for this species. The number of White-billed Divers Gavia adamsii was the highest reported since 1991. This species is probably a common winter guest from Nord-Tr&oslash;ndelag county and northwards. Manx Shearwaters Puffinus puffinus were also recorded in good numbers in 2001, the third best year since 1991. There was a further increase in numbers at the recently established colonies of Great Cormorant Phalacrocorax carbo of the subspecies sinensis at &Oslash;ra (&Oslash;F), where the first confirmed breeding was in 1997. White-tailed Eagles Haliaeetus albicilla have steadily increased in numbers and also expanded their breeding distribution southwards. Breeding is now documented in both Rogaland and Vest-Agder counties and a further expansion is expected. The Osprey Pandion haliaetus is another species that is steadily expanding its range in Norway. Avocets Recurvirostra avosetta, however, is now very unusual, with only one individual in 2001, a record low number. Several shorebirds, such as Northern Lapwings Vanellus vanellus, Great Knots Calidris canutus, Sanderlings Calidris alba, Jack Snipes Lymnocryptes minimus, Woodcocks Scolopax rusticola and Bar-tailed Godwits Limosa lapponica wintered in higher numbers than usual in 2001, probably due to winter temperatures above normal. Pomarine Skuas Stercorarius pomarinus occurred in record numbers in 2001, and also Long-tailed Skuas Stercorarius longicaudus were recorded in good numbers on migration. Furthermore, numbers of Iceland Gulls Larus glaucoides recorded were the highest since 1991, while Turtle Doves Streptopelia turtur experienced another poor year. Good numbers of Snowy Owls Bubo scandiaca were still present in 2001 after the record setting year of 2000. Kingfishers Alcedo atthis also had a good year with one breeding attempt recorded. The number of Hoopoes Upupa epops was the second best since 1991. The occurrences of Richard&rsquo;s Pipits Anthus richardi, Barred Warblers Sylvia nisoria and Marsh Warblers Acrocephalus palustris were the highest ever recorded, and Red-throated Pipits Anthus cervinus showed another good year, equalling the record numbers of 2000. Blackcaps Sylvia atricapilla wintered in record numbers. Stonechats Saxicola torquata, Red-breasted Flycatchers Ficedula parva, Great Grey Shrikes Lanius excubitor and Arctic Redpolls Carduelis hornemanni all experienced second best numbers since 1991. However, traditional winter invasion species such as Pine Grosbeaks Pinicola enucleator and Two-barred Crossbills Loxia leucoptera appeared in low numbers in 2001. The Hawfinch Coccothraustes coccothraustes still shows a marked increase in the north of its distribution, especially in the Tr&oslash;ndelag counties, while the situation is not as bright for Ortolan Buntings Emberiza hortulana, which continues to decline in numbers and now are in danger of becoming lost as a member of the Norwegian avifauna.

Lack of social hierarchy in wintering white-tailed eagles (Haliaeetus albicilla) when scavenging

We studied agonistic interactions and the influence of dominance relationships on access to food in groups of wintering white-tailed eagles (Haliaeetus albicilla) when scavenging fish carcasses in Eastern Poland. The data did not conform to the arrangements of a linear hierarchy. No winner-loser effect on fight success was observed: winners of aggressive encounters could turn into losers at repeated interactions during the same day. There was no reduction in overt aggression rate and no increase in linearity of dominance hierarchy over time. Immature and adult birds did not differ significantly in the rate of initiated aggressive interactions or in the time spent feeding. The outcome of agonistic contests did not depend on the estimated prior residence in the study area or time spent feeding beforehand, however older birds better defended their feeding positions against younger conspecifics. We suggest that unstable dominance relationships in white-tailed eagles may result from (a) some attributes of social organization of wintering flocks, (b) the effect of hunger on the outcomes of agonistic interactions masking the true competitive ability of the contestants, and (c) the ontogenetic tendency of young birds to challenge dominant opponents.