Spatial and temporal differences in migration strategies among endangered European Greater Spotted Eagles Clanga clanga

Summary Understanding connectivity between migratory bird breeding and wintering grounds is essential for range-wide planning of conservation activities. We used GPS tracking to explore the migration of 28 ‘Endangered’ Greater Spotted Eagles, Clanga clanga from three remaining European breeding populations towards their wintering range, and to identify population and sex-specific patterns in selection of wintering sites. The tracked eagles wintered in three continents, 46% in Africa (mostly Eastern Sahel), 43% across southern Europe (mostly Greece) and 11% in Asia (the Middle East). Migratory connectivity was weak (rM = 0.16), and the population spread across the wintering range was large (1,917 km). The three studied populations differed in their migration strategy, with northerly, Estonian breeders all wintering in Southern Europe, and Polish and Belarusian breeders divided between Southern Europe and Africa. Migration strategy was different between Belarusian males and females, with males more likely to winter in Africa than Europe, and on average, migrating 2,500 km further south than females. Migration to Africa took longer, but was partly compensated by higher migration speeds. Greater Spotted Eagles wintered in wetland sites throughout their wintering range, with 15 of 29 birds wintering in internationally or nationally protected sites (including 12 Ramsar sites). Nearly a third of European winterers stayed in the same Greek national park, perhaps indicating a limitation of suitable sites in Europe due to wetland loss or degradation. This highlights the importance of protected wetlands to this species, but also shows their vulnerability to future wetland degradation. Only two of 14 wintering sites in Africa were under protection, showing a potential mismatch between protection of females and males in their wintering grounds.

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Malarial parasites as geographical markers in migratory birds?

Biology Letters ◽

10.1098/rsbl.2005.0429 ◽

2006 ◽

Vol 2 (2) ◽

pp. 213-216 ◽

Cited By ~ 31

Author(s):

Sylvia M Fallon ◽

Robert C Fleischer ◽

Gary R Graves

Keyword(s):

North America ◽

Migratory Birds ◽

Wide Distribution ◽

Specific Information ◽

Population Movements ◽

Site Specific ◽

Dendroica Caerulescens ◽

Bird Populations ◽

Breeding Populations ◽

Wintering Range

We tested the hypothesis that malarial parasites ( Plasmodium and Haemoproteus ) of black-throated blue warblers ( Dendroica caerulescens ) provide sufficient geographical signal to track population movements between the warbler's breeding and wintering habitats in North America. Our results from 1083 warblers sampled across the species' breeding range indicate that parasite lineages are geographically widespread and do not provide site-specific information. The wide distribution of malarial parasites probably reflects postnatal dispersal of their hosts as well as mixing of breeding populations on the wintering range. When compared to geographically structured parasites of sedentary Caribbean songbirds, patterns of malarial infections in black-throated blue warblers suggest that host–malaria dynamics of migratory and sedentary bird populations may be subject to contrasting selection pressures.

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Inferring the links between breeding and wintering grounds in a Palearctic– African migratory bird, the Great Reed Warbler, using mitochondrial DNA data

African Zoology ◽

10.1080/15627020.2015.1055301 ◽

2015 ◽

Vol 50 (3) ◽

pp. 241-248 ◽

Cited By ~ 3

Author(s):

Naglaa El-Arabany ◽

Marjorie Sorensen ◽

Bengt Hansson

Keyword(s):

Mitochondrial Dna ◽

Migratory Bird ◽

Great Reed Warbler ◽

Reed Warbler ◽

Wintering Grounds

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When and where mortality occurs throughout the annual cycle changes with age in a migratory bird: individual vs population implications

Scientific Reports ◽

10.1038/s41598-019-54026-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Fabrizio Sergio ◽

Giacomo Tavecchia ◽

Alessandro Tanferna ◽

Julio Blas ◽

Guillermo Blanco ◽

...

Keyword(s):

Population Dynamics ◽

Annual Cycle ◽

Migratory Bird ◽

Seasonal Effects ◽

Conservation Strategies ◽

Gps Tracking ◽

Milvus Migrans ◽

Black Kite ◽

Breeding Migration

AbstractThe annual cycle of most animals is structured into discrete stages, such as breeding, migration and dispersal. While there is growing appreciation of the importance of different stages of an organism’s annual cycle for its fitness and population dynamics, almost nothing is known about if and how such seasonal effects can change through a species lifespan. Here, we take advantage of the opportunity offered by a long-term satellite/GPS-tracking study and a reliable method of remote death-detection to show that certain stages of both the annual and life cycle of a migratory long-lived raptor, the Black kite Milvus migrans, may represent sensitive bottlenecks for survival. In particular, migratory journeys caused bursts of concentrated-mortality throughout life, but the relative importance of stage-specific survival changed with age. On the other hand, the balance between short-stages of high mortality and long-stages of low mortality made population-growth similarly dependent on all portions of the annual cycle. Our results illustrate how the population dynamics of migratory organisms can be inextricably linked to ecological pressures balanced over multiple stages of the annual cycle and thus multiple areas of the globe, suggesting the frequent need for challenging conservation strategies targeting all portions of a species year-round range.

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Migratory connectivity and population-specific migration routes in a long-distance migratory bird

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.2897 ◽

2014 ◽

Vol 281 (1778) ◽

pp. 20132897 ◽

Cited By ~ 74

Author(s):

Christiane Trierweiler ◽

Raymond H. G. Klaassen ◽

Rudi H. Drent ◽

Klaus-Michael Exo ◽

Jan Komdeur ◽

...

Keyword(s):

Migratory Bird ◽

Habitat Characteristics ◽

Sub Saharan Africa ◽

Migratory Connectivity ◽

Migration Routes ◽

Long Distance ◽

Comprehensive Overview ◽

Migration System ◽

Breeding Populations ◽

Wintering Areas

Knowledge about migratory connectivity, the degree to which individuals from the same breeding site migrate to the same wintering site, is essential to understand processes affecting populations of migrants throughout the annual cycle. Here, we study the migration system of a long-distance migratory bird, the Montagu's harrier Circus pygargus , by tracking individuals from different breeding populations throughout northern Europe. We identified three main migration routes towards wintering areas in sub-Saharan Africa. Wintering areas and migration routes of different breeding populations overlapped, a pattern best described by ‘weak (diffuse) connectivity’. Migratory performance, i.e. timing, duration, distance and speed of migration, was surprisingly similar for the three routes despite differences in habitat characteristics. This study provides, to our knowledge, a first comprehensive overview of the migration system of a Palaearctic-African long-distance migrant. We emphasize the importance of spatial scale (e.g. distances between breeding populations) in defining patterns of connectivity and suggest that knowledge about fundamental aspects determining distribution patterns, such as the among-individual variation in mean migration directions, is required to ultimately understand migratory connectivity. Furthermore, we stress that for conservation purposes it is pivotal to consider wintering areas as well as migration routes and in particular stopover sites.

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Carry-over effects of conditions at the wintering grounds on breeding plumage signals in a migratory bird: roles of phenotypic plasticity and selection

Journal of Evolutionary Biology ◽

10.1111/jeb.12892 ◽

2016 ◽

Vol 29 (8) ◽

pp. 1569-1584 ◽

Cited By ~ 9

Author(s):

P. E. Järvistö ◽

S. Calhim ◽

W. Schuett ◽

P. M. Sirkiä ◽

W. Velmala ◽

...

Keyword(s):

Phenotypic Plasticity ◽

Migratory Bird ◽

Wintering Grounds ◽

Breeding Plumage ◽

Carry Over

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The Use of Nocturnal Flights for Barrier Crossing in a Diurnally Migrating Songbird: Implications for Our Understanding of Fly-and-Forage Migration Strategies

10.21203/rs.3.rs-133338/v1 ◽

2020 ◽

Author(s):

Christie D. Lavallée ◽

Saeedeh Bani Assadi ◽

Alicia M. Korpach ◽

James D. Ray ◽

Jason D Fischer ◽

...

Keyword(s):

Open Water ◽

Gps Tracking ◽

Migration Strategy ◽

Barrier Crossing ◽

Migration Patterns ◽

Migration Strategies ◽

The Caribbean ◽

Migratory Movements ◽

High Degree ◽

Circadian Patterns

Abstract Background: The migration patterns of land birds can generally be divided into those species that migrate principally during the day and those that migrate during the night. Some species may show individual plasticity in the use of day or night flight, particularly when crossing large, open-water or desert barriers. However, individual plasticity in circadian patterns of migratory flights in diurnal songbirds that use a fly-and-forage migration strategy has never been investigated. Methods: We used high precision GPS tracking of a diurnal, migratory swallow Purple martin, (Progne subis), to determine whether individuals were flexible in their spring migration strategies to include some night flight, particularly at barrier crossing.Results: We found that individuals made large (sometimes >1000 km), open-water crossings of the Caribbean Sea and the Gulf of Mexico that included the use of night flight. Some birds-initiated barrier crossing flights at night, demonstrating that night flight is not only used to complete barrier crossings but may confer other advantages for diurnal birds. All birds also used some, shorter night flights when making overland flights not associated with barrier crossing. Birds were more likely to initiate water crossings with supportive northward winds, and preliminary data suggest that moonlight may influence nighttime migratory movements.Conclusions: Overall, our results demonstrate an unexpected high degree of individual plasticity in migration strategies on a circadian scale in a ‘diurnal’ songbird and suggest that barrier crossing at night may complement fly-and-forage migration strategies.

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Growing points in Neotropical migratory bird conservation

Bird Conservation International ◽

10.1017/s0959270900002677 ◽

1994 ◽

Vol 4 (2-3) ◽

pp. 69-70

Author(s):

Eugene S. Morton ◽

KimberLey Young ◽

Mario A. Ramos

Keyword(s):

North America ◽

Migratory Bird ◽

Bird Conservation ◽

Wintering Grounds ◽

Breeding Grounds ◽

Tropical America

Millions of birds migrate every year from breeding grounds in North America to wintering grounds in tropical America. Some 50% of the species which breed in North America spend the winter in the Neotropics. Although these migrations have been studied quite extensively, austral, altitudinal and local movements of birds are also very important but poorly documented to date.

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