Many populations of long-distance migrants are declining and there is increasing evidence that de... more Many populations of long-distance migrants are declining and there is increasing evidence that declines may be caused by factors operating outside the breeding season. Among the four vulture species breeding in the western Palaearctic, the species showing the steepest population decline, the Egyptian Vulture Neophron percnopterus, is a longdistance migrant wintering in Africa. However, the flyways and wintering areas of the species are only known for some populations, and without knowledge of where mortality occurs, effective conservation management is not possible. We tracked 19 juvenile Egyptian Vultures from the declining breeding population on the Balkan Peninsula between 2010 and 2014 to estimate survival and identify important migratory routes and wintering areas for this species. Mortality during the first autumn migration was high (monthly survival probability 0.75) but mortality during migration was exclusively associated with suboptimal navigation. All birds from western breeding areas and three birds from central and eastern breeding areas attempted to fly south over the Mediterranean Sea, but only one in 10 birds survived this route, probably due to stronger tailwind. All eight birds using the migratory route via Turkey and the Middle East successfully completed their first autumn migration. Of 14 individual and environmental variables examined to explain why juvenile birds did or did not successfully complete their first migration, the natal origin of the bird was the most influential. We speculate that in a declining population with fewer experienced adults, an increasing proportion of juvenile birds are forced to migrate without conspecific guidance, leading to high mortality as a consequence of following sub-optimal migratory routes. Juvenile Egyptian Vultures wintered across a vast range of the Sahel and eastern Africa, and had large movement ranges with core use areas at intermediate elevations in savannah, cropland or desert. Two birds were shot in Africa, where several significant threats exist for vultures at continental scales. Given the broad distribution of the birds and threats, effective conservation in Africa will be challenging and will require long-term investment. We recommend that in the short term, more efficient conservation could target narrow migration corridors in southern Turkey and the Middle East, and known congregation sites in African wintering areas.
Monitoring raptors along migration corridors can be used to assess changes in population size. Th... more Monitoring raptors along migration corridors can be used to assess changes in population size. The Balkan population of the endangered Egyptian Vulture Neophron percnopterus is declining rapidly, but no trend information exists of the larger adjacent population in western Turkey. In September 2013, we explored 13 localities around the gulf of Iskenderun, southern Turkey, to establish whether long-term migration monitoring would be possible in the area. We found that the small hills north of the gulf of Iskenderun were consistently better for observing migration than locations at the Belen pass, southeast of the gulf. Long-term raptor monitoring should be established at three points north of the gulf of Iskenderun near the villages of Sarimazi and Selimiye. If attended by 2–3 observers mid August–mid October, these observation points would likely allow monitoring of the majority of Egyptian Vultures migrating around the eastern coast of the Mediterranean sea. Summing observations at ...
Im Jahr 2003 wurde die Heuschreckenfauna der jungen Duneninsel Trischen im schleswig-holsteinisch... more Im Jahr 2003 wurde die Heuschreckenfauna der jungen Duneninsel Trischen im schleswig-holsteinischen Wattenmeer untersucht. Diese Insel entstand im Mittelalter und besas nie eine trockene Verbindung zum Festland. Derzeit liegt Trischen etwa 10 km westlich der Kustenlinie. Es wurden sieben Heuschreckenarten gefunden, darunter vier Laub- und drei Feldheuschrecken. Fur drei Arten (Conocephalus dorsalis, Chorthippus apricarius, Ch. albomarginatus) konnte die Bodenstandigkeit auf der Insel nachgewiesen werden. Alle anderen Arten wurden als Gaste eingestuft, deren Ausbreitung nach Trischen vermutlich durch die trockenwarmeWitterung im Untersuchungsjahr begunstigt wurde. Das Arteninventar auf Trischen ist leicht hoher als auf anderen jungen Duneninseln, was vor allem durch das Vorkommen von Ch. apricarius bedingt ist. Von dieser Art wurden fast nur makroptere Individuen beobachtet, dennoch ist die Besiedlung Trischens vermutlich anthropogen. Fur die mittlere Zukunft ist die Ansiedlung von T...
On 12 April 2011 we observed a second-year male Orchard Oriole ( Icterus spurius ) in suburban dr... more On 12 April 2011 we observed a second-year male Orchard Oriole ( Icterus spurius ) in suburban dry gardens on Mongo Hill, Montserrat, West Indies. To our knowledge, this is the first record of this species on Montserrat. El 12 de abril de 2011 observamos un macho del segundo ano de Icterus spurius en los jardines secos suburbanos de Mongo Hill, Montserrat, Indias Occidentales. Hasta donde conocemos, este es el primer registro de esta especie en Montserrat. Le 12 avril 2011, un Oriole des Vergers ( Icterus spurius ) mâle de deuxieme annee a ete observe dans les jardins secs de la banlieue sur Mongo Hill, Montserrat, Antilles. Il semblerait que ce soit la premiere mention de cette espece sur Montserrat.
Neurobasis sp. nov., Calopterygidae Summary The odonate fauna of Papua New Guinea (PNG) is specie... more Neurobasis sp. nov., Calopterygidae Summary The odonate fauna of Papua New Guinea (PNG) is species rich but poorly studied. Geographic ranges, ecology, and thus conservation status of many species are unknown. In this study I provide an inventory of two sites within the largest formally protected forest area in PNG, the Crater Mountain Wildlife Management Area. I sampled odonates for a total of 112 days in a pristine forest site and for 36 days in a traditional garden village, and worked with local communities to increase the awareness of dragonflies in the area. I found a total of 78 species (60 Zygoptera, 18 Anisoptera) from 13 families, including at least six currently undescribed species.
Summary Changes in food availability that lead to lower reproductive output or lower survival pro... more Summary Changes in food availability that lead to lower reproductive output or lower survival probability are important drivers of the widespread declines in vulture populations. Permanent feeding stations for scavengers, such as vulture restaurants or rubbish dumps, may have both positive and negative effects on reproductive parameters. Here we examine the effects of the closure of a large communal rubbish dump on breeding success and fledging rate of a dense population of the ’Endangered’ Egyptian Vulture Neophron percnopterus in central Turkey to assess whether the closure may have affected the population. We monitored territories from 2011 to 2016, and tested whether the closure of the rubbish dump in early 2015 coincided with changes in reproductive parameters while accounting for confounding variables such as weather and the availability of other predictable foraging opportunities. We found an average productivity of 0.78 fledglings per territorial pair before the dump closed ...
Knowing the spatial scales at which effective management can be implemented is fundamental for co... more Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient. Here the space use patterns of seabirds were examined to provide guidance on whether conservation management approaches should be tailored for taxonomic groups with different movement characteristics. Seabird tracking data were synthesised from 5419 adult breeding individuals of 52 species in ten families that were collected in the Atlantic Ocean basin between 1998 and 2017. Two key aspects of spatial distribution were quantified, namely how far seabirds ranged from their colony, and to what extent individuals from the same colony used the same areas at sea. There was evidence for substantial differences in patterns of space-use among the ten studied seabird families, indicating that several alternative conservation management approaches are needed. Several species exhibited large foraging ranges and little aggregation at sea, indicating that area-based conservation solutions would have to be extremely large to adequately protect such species. The results highlight that short-ranging and aggregating species such as cormorants, auks, some penguins, and gulls would benefit from conservation approaches at relatively small spatial scales during their breeding season. However, improved regulation of fisheries, bycatch, pollution and other threats over large spatial scales will be needed for wide-ranging and dispersed species such as albatrosses, petrels, storm petrels and frigatebirds.
Petrels (Procellariidae) are a highly diverse family of seabirds, many of which are globally thre... more Petrels (Procellariidae) are a highly diverse family of seabirds, many of which are globally threatened due to the impact of invasive species on breeding populations. While predation by invasive cats and rats has led to the extinction of petrel populations, the impact of invasive house mice Mus musculus is slower and less well documented. However, mice impact small burrow-nesting species such as MacGillivray’s prion Pachyptila macgillivrayi, a species classified as endangered because it has been extirpated on islands in the Indian Ocean by introduced rodents. We use historic abundance data and demographic monitoring data from 2014 to 2020 to predict the population trajectory of MacGillivray’s prion on Gough Island with and without a mouse eradication using a stochastic integrated population model. Given very low annual breeding success (0.01 fledglings per breeding pair in ‘poor’ years (83%) or 0.38 in ‘good’ years (17%), n = 320 nests over 6 years) mainly due to mouse predation, ou...
Summary The United Nations Sustainable Development Goals aim to improve livelihoods and maintain ... more Summary The United Nations Sustainable Development Goals aim to improve livelihoods and maintain functioning ecosystems, and include the provision of electricity and the prevention of desertification. We show that the pursuit of those two goals can lead to developments that put critical ecosystem functions at risk. Vultures are scavengers that provide sanitary ecosystem services, but their populations across Africa are declining due to poisoning, electrocution, and collision with power infrastructure. The extent to which the pursuit of sustainable development threatens vultures in Africa is unclear. We surveyed 227 km of powerlines in Ethiopia, which revealed bird mortality (0.15 vulture carcasses / km) at power infrastructure constructed under a National Electrification Programme to provide universal electricity access by 2025. We also interviewed 190 local pastoralists in 10 areas about livelihood challenges, which revealed that the bush Prosopis juliflora, which was originally in...
Colonially breeding birds and mammals form some of the largest gatherings of apex predators in th... more Colonially breeding birds and mammals form some of the largest gatherings of apex predators in the natural world and have provided model systems for studying mechanisms of population regulation in animals. According to one influential hypothesis, intense competition for food among large numbers of spatially constrained foragers should result in a zone of prey depletion surrounding such colonies, ultimately limiting their size. However, while indirect and theoretical support for this phenomenon, known as “Ashmole’s halo,” has steadily accumulated, direct evidence remains exceptionally scarce. Using a combination of vessel-based surveys and Global Positioning System tracking, we show that pelagic seabirds breeding at the tropical island that first inspired Ashmole’s hypothesis do indeed deplete their primary prey species (flying fish; Exocoetidae spp.) over a considerable area, with reduced prey density detectable >150 km from the colony. The observed prey gradient was mirrored by ...
One of the most important breeding colonies for gadfly petrels in the sub-tropics, Henderson Isla... more One of the most important breeding colonies for gadfly petrels in the sub-tropics, Henderson Island in the South Pacific Ocean, was subjected to a rat eradication attempt in 2011, but the eradication failed. Here we examine whether the current population status of the endemic Henderson Petrel Pterodroma atrata is consistent with an ongoing population decline. We collected basic biological information on Henderson Petrels in 2015 to compare estimates of breeding population size and nest survival to data from 1991. We found that the extrapolated population size of 19 987 pairs was marginally higher than the comparable estimate of 18 668 in 1991. We also estimated the nest survival of 25 nests to be 28.5%, and most nest failures occurred within 7 days of hatching when chicks were killed by rats (n = 3) or a crab (n = 1). Breeding success was higher than in 1991, and possibly sufficient for a stable population. Although differences in survey effort render it difficult to directly compare estimates from 1991 and 2015, there is currently no evidence that the conservation status of the Henderson Petrel has deteriorated since it was listed as 'Endangered' by the IUCN.
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Migratory marine species cross political borders and enter the high seas, where the lack of an ef... more Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory spec...
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Disentangling individual-and population-level variation in migratory movements is necessary for u... more Disentangling individual-and population-level variation in migratory movements is necessary for understanding migration at the species level. However, very few studies have analyzed these patterns across large portions of species' distributions. We compiled a large telemetry dataset on the globally endangered Egyptian Vulture Neophron percnopterus (94 individuals, 188 completed migratory journeys), tracked across ∼70% of the species' global range, to analyze spatial and temporal variability of migratory movements within and among individuals and populations. We found high migratory connectivity at large spatial scales (i.e., different subpopulations showed little overlap in wintering areas), but very diffuse migratory connectivity within subpopulations, with wintering ranges up to 4,000 km apart for birds breeding in the same region and each subpopulation visiting up to 28 countries (44 in total). Additionally, Egyptian Phipps et al. Egyptian Vulture Migration Flexibility Vultures exhibited a high level of variability at the subpopulation level and flexibility at the individual level in basic migration parameters. Subpopulations differed significantly in travel distance and straightness of migratory movements, while differences in migration speed and duration differed as much between seasons and among individuals within subpopulations as between subpopulations. The total distances of the migrations completed by individuals from the Balkans and Caucasus were up to twice as long and less direct than those in Western Europe, and consequently were longer in duration, despite faster migration speeds. These differences appear to be largely attributable to more numerous and wider geographic barriers (water bodies) along the eastern flyway. We also found that adult spring migrations to Western Europe and the Balkans were longer and slower than fall migrations. We encourage further research to assess the underlying mechanisms for these differences and the extent to which environmental change could affect Egyptian Vulture movement ecology and population trends.
Many populations of long-distance migrants are declining and there is increasing evidence that de... more Many populations of long-distance migrants are declining and there is increasing evidence that declines may be caused by factors operating outside the breeding season. Among the four vulture species breeding in the western Palaearctic, the species showing the steepest population decline, the Egyptian Vulture Neophron percnopterus, is a longdistance migrant wintering in Africa. However, the flyways and wintering areas of the species are only known for some populations, and without knowledge of where mortality occurs, effective conservation management is not possible. We tracked 19 juvenile Egyptian Vultures from the declining breeding population on the Balkan Peninsula between 2010 and 2014 to estimate survival and identify important migratory routes and wintering areas for this species. Mortality during the first autumn migration was high (monthly survival probability 0.75) but mortality during migration was exclusively associated with suboptimal navigation. All birds from western breeding areas and three birds from central and eastern breeding areas attempted to fly south over the Mediterranean Sea, but only one in 10 birds survived this route, probably due to stronger tailwind. All eight birds using the migratory route via Turkey and the Middle East successfully completed their first autumn migration. Of 14 individual and environmental variables examined to explain why juvenile birds did or did not successfully complete their first migration, the natal origin of the bird was the most influential. We speculate that in a declining population with fewer experienced adults, an increasing proportion of juvenile birds are forced to migrate without conspecific guidance, leading to high mortality as a consequence of following sub-optimal migratory routes. Juvenile Egyptian Vultures wintered across a vast range of the Sahel and eastern Africa, and had large movement ranges with core use areas at intermediate elevations in savannah, cropland or desert. Two birds were shot in Africa, where several significant threats exist for vultures at continental scales. Given the broad distribution of the birds and threats, effective conservation in Africa will be challenging and will require long-term investment. We recommend that in the short term, more efficient conservation could target narrow migration corridors in southern Turkey and the Middle East, and known congregation sites in African wintering areas.
Monitoring raptors along migration corridors can be used to assess changes in population size. Th... more Monitoring raptors along migration corridors can be used to assess changes in population size. The Balkan population of the endangered Egyptian Vulture Neophron percnopterus is declining rapidly, but no trend information exists of the larger adjacent population in western Turkey. In September 2013, we explored 13 localities around the gulf of Iskenderun, southern Turkey, to establish whether long-term migration monitoring would be possible in the area. We found that the small hills north of the gulf of Iskenderun were consistently better for observing migration than locations at the Belen pass, southeast of the gulf. Long-term raptor monitoring should be established at three points north of the gulf of Iskenderun near the villages of Sarimazi and Selimiye. If attended by 2–3 observers mid August–mid October, these observation points would likely allow monitoring of the majority of Egyptian Vultures migrating around the eastern coast of the Mediterranean sea. Summing observations at ...
Im Jahr 2003 wurde die Heuschreckenfauna der jungen Duneninsel Trischen im schleswig-holsteinisch... more Im Jahr 2003 wurde die Heuschreckenfauna der jungen Duneninsel Trischen im schleswig-holsteinischen Wattenmeer untersucht. Diese Insel entstand im Mittelalter und besas nie eine trockene Verbindung zum Festland. Derzeit liegt Trischen etwa 10 km westlich der Kustenlinie. Es wurden sieben Heuschreckenarten gefunden, darunter vier Laub- und drei Feldheuschrecken. Fur drei Arten (Conocephalus dorsalis, Chorthippus apricarius, Ch. albomarginatus) konnte die Bodenstandigkeit auf der Insel nachgewiesen werden. Alle anderen Arten wurden als Gaste eingestuft, deren Ausbreitung nach Trischen vermutlich durch die trockenwarmeWitterung im Untersuchungsjahr begunstigt wurde. Das Arteninventar auf Trischen ist leicht hoher als auf anderen jungen Duneninseln, was vor allem durch das Vorkommen von Ch. apricarius bedingt ist. Von dieser Art wurden fast nur makroptere Individuen beobachtet, dennoch ist die Besiedlung Trischens vermutlich anthropogen. Fur die mittlere Zukunft ist die Ansiedlung von T...
On 12 April 2011 we observed a second-year male Orchard Oriole ( Icterus spurius ) in suburban dr... more On 12 April 2011 we observed a second-year male Orchard Oriole ( Icterus spurius ) in suburban dry gardens on Mongo Hill, Montserrat, West Indies. To our knowledge, this is the first record of this species on Montserrat. El 12 de abril de 2011 observamos un macho del segundo ano de Icterus spurius en los jardines secos suburbanos de Mongo Hill, Montserrat, Indias Occidentales. Hasta donde conocemos, este es el primer registro de esta especie en Montserrat. Le 12 avril 2011, un Oriole des Vergers ( Icterus spurius ) mâle de deuxieme annee a ete observe dans les jardins secs de la banlieue sur Mongo Hill, Montserrat, Antilles. Il semblerait que ce soit la premiere mention de cette espece sur Montserrat.
Neurobasis sp. nov., Calopterygidae Summary The odonate fauna of Papua New Guinea (PNG) is specie... more Neurobasis sp. nov., Calopterygidae Summary The odonate fauna of Papua New Guinea (PNG) is species rich but poorly studied. Geographic ranges, ecology, and thus conservation status of many species are unknown. In this study I provide an inventory of two sites within the largest formally protected forest area in PNG, the Crater Mountain Wildlife Management Area. I sampled odonates for a total of 112 days in a pristine forest site and for 36 days in a traditional garden village, and worked with local communities to increase the awareness of dragonflies in the area. I found a total of 78 species (60 Zygoptera, 18 Anisoptera) from 13 families, including at least six currently undescribed species.
Summary Changes in food availability that lead to lower reproductive output or lower survival pro... more Summary Changes in food availability that lead to lower reproductive output or lower survival probability are important drivers of the widespread declines in vulture populations. Permanent feeding stations for scavengers, such as vulture restaurants or rubbish dumps, may have both positive and negative effects on reproductive parameters. Here we examine the effects of the closure of a large communal rubbish dump on breeding success and fledging rate of a dense population of the ’Endangered’ Egyptian Vulture Neophron percnopterus in central Turkey to assess whether the closure may have affected the population. We monitored territories from 2011 to 2016, and tested whether the closure of the rubbish dump in early 2015 coincided with changes in reproductive parameters while accounting for confounding variables such as weather and the availability of other predictable foraging opportunities. We found an average productivity of 0.78 fledglings per territorial pair before the dump closed ...
Knowing the spatial scales at which effective management can be implemented is fundamental for co... more Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient. Here the space use patterns of seabirds were examined to provide guidance on whether conservation management approaches should be tailored for taxonomic groups with different movement characteristics. Seabird tracking data were synthesised from 5419 adult breeding individuals of 52 species in ten families that were collected in the Atlantic Ocean basin between 1998 and 2017. Two key aspects of spatial distribution were quantified, namely how far seabirds ranged from their colony, and to what extent individuals from the same colony used the same areas at sea. There was evidence for substantial differences in patterns of space-use among the ten studied seabird families, indicating that several alternative conservation management approaches are needed. Several species exhibited large foraging ranges and little aggregation at sea, indicating that area-based conservation solutions would have to be extremely large to adequately protect such species. The results highlight that short-ranging and aggregating species such as cormorants, auks, some penguins, and gulls would benefit from conservation approaches at relatively small spatial scales during their breeding season. However, improved regulation of fisheries, bycatch, pollution and other threats over large spatial scales will be needed for wide-ranging and dispersed species such as albatrosses, petrels, storm petrels and frigatebirds.
Petrels (Procellariidae) are a highly diverse family of seabirds, many of which are globally thre... more Petrels (Procellariidae) are a highly diverse family of seabirds, many of which are globally threatened due to the impact of invasive species on breeding populations. While predation by invasive cats and rats has led to the extinction of petrel populations, the impact of invasive house mice Mus musculus is slower and less well documented. However, mice impact small burrow-nesting species such as MacGillivray’s prion Pachyptila macgillivrayi, a species classified as endangered because it has been extirpated on islands in the Indian Ocean by introduced rodents. We use historic abundance data and demographic monitoring data from 2014 to 2020 to predict the population trajectory of MacGillivray’s prion on Gough Island with and without a mouse eradication using a stochastic integrated population model. Given very low annual breeding success (0.01 fledglings per breeding pair in ‘poor’ years (83%) or 0.38 in ‘good’ years (17%), n = 320 nests over 6 years) mainly due to mouse predation, ou...
Summary The United Nations Sustainable Development Goals aim to improve livelihoods and maintain ... more Summary The United Nations Sustainable Development Goals aim to improve livelihoods and maintain functioning ecosystems, and include the provision of electricity and the prevention of desertification. We show that the pursuit of those two goals can lead to developments that put critical ecosystem functions at risk. Vultures are scavengers that provide sanitary ecosystem services, but their populations across Africa are declining due to poisoning, electrocution, and collision with power infrastructure. The extent to which the pursuit of sustainable development threatens vultures in Africa is unclear. We surveyed 227 km of powerlines in Ethiopia, which revealed bird mortality (0.15 vulture carcasses / km) at power infrastructure constructed under a National Electrification Programme to provide universal electricity access by 2025. We also interviewed 190 local pastoralists in 10 areas about livelihood challenges, which revealed that the bush Prosopis juliflora, which was originally in...
Colonially breeding birds and mammals form some of the largest gatherings of apex predators in th... more Colonially breeding birds and mammals form some of the largest gatherings of apex predators in the natural world and have provided model systems for studying mechanisms of population regulation in animals. According to one influential hypothesis, intense competition for food among large numbers of spatially constrained foragers should result in a zone of prey depletion surrounding such colonies, ultimately limiting their size. However, while indirect and theoretical support for this phenomenon, known as “Ashmole’s halo,” has steadily accumulated, direct evidence remains exceptionally scarce. Using a combination of vessel-based surveys and Global Positioning System tracking, we show that pelagic seabirds breeding at the tropical island that first inspired Ashmole’s hypothesis do indeed deplete their primary prey species (flying fish; Exocoetidae spp.) over a considerable area, with reduced prey density detectable >150 km from the colony. The observed prey gradient was mirrored by ...
One of the most important breeding colonies for gadfly petrels in the sub-tropics, Henderson Isla... more One of the most important breeding colonies for gadfly petrels in the sub-tropics, Henderson Island in the South Pacific Ocean, was subjected to a rat eradication attempt in 2011, but the eradication failed. Here we examine whether the current population status of the endemic Henderson Petrel Pterodroma atrata is consistent with an ongoing population decline. We collected basic biological information on Henderson Petrels in 2015 to compare estimates of breeding population size and nest survival to data from 1991. We found that the extrapolated population size of 19 987 pairs was marginally higher than the comparable estimate of 18 668 in 1991. We also estimated the nest survival of 25 nests to be 28.5%, and most nest failures occurred within 7 days of hatching when chicks were killed by rats (n = 3) or a crab (n = 1). Breeding success was higher than in 1991, and possibly sufficient for a stable population. Although differences in survey effort render it difficult to directly compare estimates from 1991 and 2015, there is currently no evidence that the conservation status of the Henderson Petrel has deteriorated since it was listed as 'Endangered' by the IUCN.
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Migratory marine species cross political borders and enter the high seas, where the lack of an ef... more Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory spec...
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Disentangling individual-and population-level variation in migratory movements is necessary for u... more Disentangling individual-and population-level variation in migratory movements is necessary for understanding migration at the species level. However, very few studies have analyzed these patterns across large portions of species' distributions. We compiled a large telemetry dataset on the globally endangered Egyptian Vulture Neophron percnopterus (94 individuals, 188 completed migratory journeys), tracked across ∼70% of the species' global range, to analyze spatial and temporal variability of migratory movements within and among individuals and populations. We found high migratory connectivity at large spatial scales (i.e., different subpopulations showed little overlap in wintering areas), but very diffuse migratory connectivity within subpopulations, with wintering ranges up to 4,000 km apart for birds breeding in the same region and each subpopulation visiting up to 28 countries (44 in total). Additionally, Egyptian Phipps et al. Egyptian Vulture Migration Flexibility Vultures exhibited a high level of variability at the subpopulation level and flexibility at the individual level in basic migration parameters. Subpopulations differed significantly in travel distance and straightness of migratory movements, while differences in migration speed and duration differed as much between seasons and among individuals within subpopulations as between subpopulations. The total distances of the migrations completed by individuals from the Balkans and Caucasus were up to twice as long and less direct than those in Western Europe, and consequently were longer in duration, despite faster migration speeds. These differences appear to be largely attributable to more numerous and wider geographic barriers (water bodies) along the eastern flyway. We also found that adult spring migrations to Western Europe and the Balkans were longer and slower than fall migrations. We encourage further research to assess the underlying mechanisms for these differences and the extent to which environmental change could affect Egyptian Vulture movement ecology and population trends.
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