Weak migratory connectivity,loop migration and multiple non-breeding site use in British breeding Whinchats Saxicola rubetra

Determining the links between breeding populations and the pressures, threats and conditions they experience presents a challenge for the conservation of migratory birds which can use multiple sites separated by hundreds to thousands of kilometres. Furthermore, migratory connectivity – the connections made by migrating individuals between networks of breeding and non-breeding sites – has important implications for population dynamics. The Whinchat Saxicola rubetra is declining across its range, and tracking data from a single African non-breeding site implies high migratory spread. We used geolocators to describe the migration routes and non-breeding areas of 20 Whinchats from three British breeding populations. As expected, migratory spread was high, with birds from the three populations overlapping across a wide area of West Africa. On average, in non-breeding areas, British breeding Whinchats were located 652 km apart from one another, with some likely to share non-breeding areas with individuals from breeding populations as far east as Russia. Four males made a direct non-breeding season movement to a second, more westerly, non-breeding location in January. Autumn migration was through Iberia and around the western edge of the Sahara Desert, whereas spring migration was more direct, indicating an anticlockwise loop migration. Weak migratory connectivity implies that Whinchat populations are somewhat buffered against local changes in non-breeding conditions. If non-breeding season processes have played a role in the species’ decline, then large-scale drivers are likely to be the cause, although processes operating on migration, or interactions between breeding and non-breeding processes, cannot be ruled out.     

Short‐distance migration of Wrynecks Jynx torquilla from Central European populations

European Wrynecks Jynx torquilla torquilla have generally been considered to be long‐distance Palaearctic–African migrants that spend the non‐breeding season in Sahelian Africa, where they have been reported regularly. Results from tracking individual birds showed that Wrynecks from two Central European populations migrated only relatively short distances to the Iberian Peninsula and northwestern Africa (c. 1500 km and 3000 km, respectively), compared with a minimum distance of about 4500 km to Sahelian Africa. Additionally, differences in wing lengths of populations from Central and Northern Europe support the idea of leap‐frog migration, populations from Northern Europe being long‐distance migrants with a non‐breeding distribution in Sahelian Africa.     

African Odyssey project – satellite tracking of black storks Ciconia nigra breeding at a migratory divide

The African Odyssey project focuses on studying the migration of the black stork Ciconia nigra breeding at a migratory divide. In 1995–2001, a total of 18 black storks breeding in the Czech Republic were equipped with satellite (PTT) and VHF transmitters. Of them, 11 birds were tracked during at least one migration season and three birds were tracked repeatedly. The birds migrated either across western or eastern Europe to spend the winter in tropical west or east Africa, respectively. One of the juveniles made an intermediate route through Italy where it was shot during the first autumn migration. The mean distance of autumn migration was 6,227 km. The eastern route was significantly longer than the western one (7,000 km and 5,667 km respectively). Important stopover sites were discovered in Africa and Israel. Wintering areas were found from Mauritania and Sierra Leone in the west to Ethiopia and Central African Republic in the east and south. One of the storks migrating by the eastern migration route surprisingly reached western Africa. Birds that arrived early in the wintering areas stayed longer than those arriving later. On the average, birds migrating via the western route spent 37 d on migration compared to 80 d for birds migrating via the eastern route. The mean migration speed in the autumn was 126 km/d and the fastest stork flew 488 km/d when crossing the Sahara. The repeatedly tracked storks showed high winter site fidelity.     

Satellite tracking of Swedish Ospreys Pandion haliaetus: autumn migration routes and orientation

Autumn migration routes and orientation of Swedish Ospreys Pandion haliaetus were studied by satellite tracking of 18 birds. Of these, 13 could be followed during the entire migration (6 females, 5 males and 2 juveniles). Most birds migrated across western and central Europe to winter in tropical West Africa. However, one juvenile flew to Cameroon and one female used a very easterly route and reached Mozambique. On average, the birds travelled a total distance of about 6700 km, with little variation except for the female wintering in Mozambique, who travelled more than 10 000 km. Of 21 stopovers (of >1 day), only five were made south of 45°N; three of these in Africa. Females departed before males and juveniles and flew to a stopover site they probably were familiar with. After 3–4 weeks there, they continued to their wintering grounds. Also males and juveniles usually made one or more stopovers. Adults seemed to travel to a known wintering site, where they remained stationary, whereas juveniles were more mobile after reaching tropical regions, probably looking for good wintering sites. Males generally left the breeding area in directions similar to the mean migratory direction, whereas a few females departed in diverging initial directions. Apart from these diversions, adult Ospreys followed very straight migratory routes, with overall mean directions of 185–209° and with mean angular deviations of 6–33°. Some juveniles also departed in diverging directions. Moreover, young birds tended to show a larger variability in orientation. Thus, the Ospreys kept a fairly straight direction and did not avoid geographical obstacles such as mountain ranges and desert areas. However, they seemed reluctant to cross large water bodies. There was no correlation between angular deviation and length of the migrational segment, indicating that the principles of orientation by vector summation may not be valid for Osprey migration. Moreover, the geographic direction of migration did not vary in accordance with variations in the magnetic declination, suggesting that the Ospreys did not orient along magnetic loxodromes.     

Timing and speed of migration in male, female and juvenile Ospreys Pandion haliaetus between Sweden and Africa as revealed by field observations, radar and satellite tracking

Breeding Ospreys were studied in southern Sweden and 13 birds were tracked by satellite telemetry on autumn migration to the African wintering grounds. This was supplemented with studies of migrating birds at Falsterbo and radar trackings from southern Sweden. Females generally left the nest site 2–3 weeks ahead of males and juveniles. Among males, failed breeders migrated significantly earlier than successful breeders. At Falsterbo, Ospreys passed in the order adult females (median 22 Aug), adult males (26 Aug) and juveniles (30 Aug). Birds tracked by radar achieved cross‐country speeds of 18–47 km/h. Most of our birds wintered in an area from The Gambia to the Ivory Coast, with one juvenile in Cameroon and one female in Mozambique. Ospreys spent on average 45 days travelling an average distance of 6742 km with no significant differences between sex and age categories. Between 0 and 44 days were used for stopovers en route. Females generally made more stopovers at northerly latitudes than males. Average speed on migration was 174 km/d, which is similar to speeds reported for other large raptors followed by satellite. Speed on travelling days was on average 257 km/d with males generally moving fastest. There was a clear tendency for lower speeds and more stopovers in Europe than during the crossing of the Sahara. Migratory activity generally took place between 8 a. m. and 5 p. m. local time and we have no indications of birds flying at night. With 9 hours travelling time the expected cross‐country speed, derived from the theory of thermal soaring flight and assuming thermal climb rates of 1–2 m/s, varies from 251 to 360 km/d, which is similar to the observed mean speed on travelling days. Even so, one male travelled 746 km/d between Sweden and Spain. Some Ospreys need a much larger fraction of travelling days than expected from theory, suggesting that they deposit fuel on the breeding grounds before departure. This is supported by a correlation between the observed fraction of days spent travelling and departure date. In late departing Ospreys, especially males and juveniles, a major part of the energy for migration is probably deposited on the breeding grounds.     

High variation reduces the value of feather stable isotope ratios in identifying new wintering areas for aquatic warblers Acrocephalus paludicola in West Africa

Stable isotope analysis of feathers can be useful in the study of seasonal interactions and migratory connectivity in birds. For the Palaearctic–African migration system, however, the lack of isotope data from feathers of known origin in Africa renders the geographic assignment of birds captured on European breeding grounds to potential wintering areas problematic. Rectrices of the threatened aquatic warbler Acrocephalus paludicola grown in Africa were sampled across six European countries to assess whether birds in different breeding populations shared similar isotopic signatures and so were likely to have wintered in the same region in Africa. Freshly grown feathers of aquatic warblers collected at the only known wintering site in Senegal showed high variation in carbon, nitrogen, and hydrogen isotope ratios. Due to similarly high variation in isotope ratios of African‐grown feathers within all breeding populations, it was not possible to determine whether different populations wintered in different regions. However, isotope signatures of 20% of birds captured on European breeding grounds fell outside the range of those captured in Senegal, suggesting a wider wintering distribution than is currently known. We therefore assessed whether the origin of these feathers could be estimated by trying to establish isotopic gradients across sub‐Saharan West Africa. Feathers of three ecologically similar surrogate species were sampled from wetlands across a 3000 km east‐west and a 2000 km north–south transect. Within‐site variation in feather isotope ratios was frequently larger than the difference predicted by gradients across West Africa. Thus, predicting the origin of individual feathers using single‐isotope gradients was not reliable. The large within‐site variability of feather isotope ratios of a habitat specialist species like the aquatic warbler indicates that using feather isotope ratios will require large sample sizes from many locations, and may thus not be an efficient tool in identifying wintering areas of Palaearctic–African migrants.     

THE PELAGIC DISTRIBUTION OF THE SOOTY SHEARWATER PROCELLARIA GRISEA

The breeding distribution of the Sooty Shearwater and the dates of its breeding season are briefly reviewed.
Records from the Southern Ocean are summarised. It is concluded that they are accounted for by non-breeding birds feeding off the ice-edge in the Australian sector of the Antarctic during the latter part of the breeding season.
The great majority of Sooty Shearwaters spend the southern winter in the Pacific Ocean. Birds from the New Zealand colonies are probably mostly found on the feeding grounds off Japan: some may make a "circular" migration around the Pacific. Birds from the Cape Horn colonies spend the southern winter in the rich areas off the western coast of North America.
Some Sooty Shearwaters spend the southern winter off the South African coasts. A number of non-breeding birds remain there throughout the summer.
The Sooty Shearwaters "wintering" in the North Atlantic are probably numbered in tens of thousands only. The distribution of records is reviewed month by month and the records from Atlantic transects are summarised. The migrations in the North Atlantic are discussed in relation to prevailing meteorological and oceanographic conditions, and food supply. It is concluded that most Sooty Shearwaters in the North Atlantic make a "circular" migration, crossing the North Atlantic from west to east in June and July, and re-crossing about September further south in the northeast trades.     

Range-wide migration corridors and non-breeding areas of a northward expanding Afro-Palaearctic migrant,the European Bee-eater Merops apiaster

Across their ranges, different populations of migratory species often use separate routes to migrate between breeding and non-breeding grounds. Recent changes in climate and land-use have led to breeding range expansions in many species but it is unclear whether these populations also establish new migratory routes, non-breeding sites and migration phenology. Thus, we compared the migration patterns of European Bee-eaters Merops apiaster from two established western (n = 5) and eastern (n = 6) breeding populations in Europe, with those from a newly founded northern population (n = 19). We aimed to relate the breeding populations to the two known non-breeding clusters in Africa, and to test for similarities of migration routes and timing between the old and new populations. Western Bee-eaters used the western flyway to destinations in West Africa; the eastern birds uniformly headed south to southern African non-breeding sites, confirming a complete separation in time and space between these long-established populations. The recently founded northern population, however, also used a western corridor, but crossed the Mediterranean further east than the western population and overwintered mainly in a new non-breeding area in southern Congo/northern Angola. The migration routes and the new non-breeding range overlapped only slightly with the western, but not with the eastern, population. In contrast, migration phenology appeared to differ between the western and both the northern and the eastern populations, with tracked birds from the western population migrating 2–4 weeks earlier. The northern population thus shares some spatial traits with western Bee-eaters, but similar phenology only with eastern population. This divergence highlights the adjustments in the timing of migration to local environmental conditions in newly founded populations, and a parallel establishment of new breeding and non-breeding sites.     

The ‘chaotic’ flight feather moult of the Steppe Buzzard Buteo buteo vulpinus

Steppe Buzzards breed in Eurasia and spend the non-breeding season in Africa. Adults moult some flight feathers during the breeding season and some during the non-breeding season. Moult is arrested during migration. The extent of moult of flight feathers in adults is highly variable between individuals in southern Africa, with the renewal of two primaries, three secondaries and five rectrices as the most frequently encountered pattern. Time spent on the non-breeding grounds in South Africa is too short to allow for a sequential moult. Moult of flight feathers is restricted to the almost synchronous dropping of a number of feathers upon arrival, with few being replaced subsequently. Any of the flight feathers can be replaced in southern Africa, and the pattern of renewal in primaries and secondaries cannot be distinguished from random. Tail feathers are replaced in an alternating (transilient) pattern. Moult in the non-breeding areas may primarily be complementary to moult on the breeding grounds, but these two partial moults per year are insufficient to renew all flight feathers annually. Middle secondaries and central tail feathers are regularly carried over to a third moult, but this is rare for primaries.     

SOME BIRDS OF CHICUMBANE,P.E.A.

Boshoff, A. F. &; Palmer, N. G. 1983. Aspects of the biology and ecology of the Osprey in the Cape Province, South Africa. Ostrich 54:189-204.

Information gathered opportunistically on the distribution, habitat, density, seasonality, timing of migration, food spectrum, feeding and hunting behaviour and periodicity, flight mode, influence of weather on hunting activity, interspecific and intraspecific interaction, general behaviour and conservation status of the Osprey Pandion haliaetus in the Cape Province, South Africa, is presented. The species is confined mainly to the coastal region and was recorded most frequently from the larger estuaries. Although it is basically a non-breeding migrant to the area, with peaks of occurrence during the austral summer, birds were recorded throughout the austral winter. A maximum density of 0,0028 Osprey/ha of surface water was determined; there is some evidence for an increase in the number of birds in the main study area from 1980 to 1982. The birds are persistent hunters and forage mainly in the littoral zone at water depths of up to 1,5 m, with a hunting activity peak at mid morning and at late afternoon. The food spectrum comprised 84–91% mullet (Mugilidae) of 20–700 g and 9–14% Mozambique Tilapia Oreochromis mossambicus. Flapping flight was preferred for hunting purposes and the implications of this are discussed. The study area is considered to provide optimal foraging conditions of windspeed and cloud cover for Ospreys. There was little aggressive interaction between Ospreys and resident Fish Eagles Haliaeetus vocifer and competition between these two species was not a major factor. Kelp Gulls Larus dominicanus harassed Ospreys with grey. The conservation status of Ospreys in the Cape Province is considered to be satisfactory at present.     

Following year-round movements in Barn Swallows using geolocators: could breeding pairs remain together during the winter?

Capsule The spatio-temporal schedule provided by geolocators suggests that a pair of Barn Swallows could have remained together during the non-breeding period. Data from four birds, of which two were a breeding pair, showed winter quarters from West to Central Africa. The tracks of the paired individuals coincided both spatially and temporally at a scale of <200?km throughout the non-breeding period, in contrast to the tracks of an unpaired male and female from the same region.     

Red-spotted Bluethroats Luscinia s. svecica migrate along the Indo-European flyway: a geolocator study

Capsule Red-spotted Bluethroats Luscinia s. svecica from two European breeding populations spent the boreal winter on the Indian sub-continent.

Aim Tracking the migration of Red-spotted Bluethroats from Europe to the hitherto unknown non-breeding areas and back.

Methods Light-level geolocators were deployed on male Bluethroats at breeding sites in the Czech Republic (n?=?10) and in Norway (n?=?30). Recorded light intensity data were used to estimate the locations of non-breeding sites and migration phenology during the annual cycle.

Results Bluethroats spent the boreal winter in India (n?=?3) and Pakistan (n?=?1), on average more than 6000?km from their breeding areas. Autumn migration started in August (n?=?1) or early September (n?=?2), and lasted for 26–74 days. Spring migration commenced on 8 and 9 April (n?=?2) and lasted for about a month. During both autumn and spring migration, birds stopped over two or three times for more than 3 days.

Conclusion This study for the first time showed where Red-spotted Bluethroats from European breeding populations stay during the boreal winter. This seems to be the first time that a passerine bird has been tracked along the Indo-European flyway.     

THE INFLUENCE OF HABITAT ON THE DISTRIBUTION AND ABUNDANCE OF PEREGRINE AND LANNER FALCONS IN SOUTH AFRICA

Jenkins, A.R. 1994. The influence of habitat on the distribution and abundance of Peregrine and Lanner Falcons in South Africa. Ostrich 65: 281–290.

The distribution and abundance of Peregrine and Lanner Falcons in South Africa was compared using recorded sightings from various sources, including the Southern African Bird Atlas Project. Falcon distributions were compared with the distribution of cliffs and vegetation, to quantify differences in the habitat preferences of the two species in the breeding and the non-breeding seasons. Lanner Falcons outnumbered Peregrine Falcons in most areas by at least 10:1. Peregrine Falcons were more habitat specific than Lanner Falcons, in terms of topographic and biotic requirements. Peregrine Falcons were largely restricted to high cliff areas throughout the year and there probably were no large-scale seasonal movements within the population. The bulk of the resident Peregrine Falcon population was found in the fynbos biome, in the southwestern Cape. Outside of this area, Peregrine Falcons were concentrated in woodlands. Lanner Falcons were less dependent on high cliffs, although cliff availability was important in defining the ranges of both species. Lanner Falcons were most common in the sour grasslands in the east of the country in the breeding season, with apparent movements in the non-breeding season into the fynbos, the Nama Karoo and the southern Kalahari. Overall, Peregrine Falcons favoured relatively closed habitats and Lanner Falcons favoured relatively open habitats. The differences in the two species' habitat preferences are proximate factors influencing distribution and abundance.     

Migration patterns of the Osprey Pandion haliaetus on the Eastern European–East African flyway

We analysed migration strategies of the Osprey Pandion haliaetus on the poorly studied Eastern European–East African flyway. Four adult birds were equipped with GPS-based satellite-transmitters or data-loggers in their breeding sites in Estonia (north-eastern Europe) and tracked to their wintering grounds in Africa and back, during up to six migration cycles. Departure times, migration routes, as well as wintering and stopover sites varied remarkably between individuals but not much between years. Stopovers (2–30 days) were made mostly in Europe and less in the Middle East (Turkey) and north-eastern Africa (Egypt). The Ospreys did not avoid flying long distances over the sea, and the sea was crossed four times during the night. The current study adds to current knowledge on Osprey migration and should help to concentrate actions on protecting important flyways and stopover locations.     

Strong migratory connectivity and seasonally shifting isotopic niches in geographically separated populations of a long-distance migrating songbird

Whether migratory animals use similar resources during continental-scale movements that characterize their annual cycles is highly relevant to both individual performances and population dynamics. Direct knowledge of the locations and resources used by migrants during non-breeding is generally scarce. Our goal was to estimate migratory connectivity of a small Palaearctic long-distance migrant, the common nightingale Luscinia megarhynchos, and to compare resources used in non-breeding areas with resources used at the breeding grounds. We tracked individuals of three geographically separated populations and characterised their stable isotope niches during breeding and non-breeding over 2 years. Individuals spent the non-breeding period in population-specific clusters from west to central Africa, indicating strong migratory connectivity at the population level. Irrespective of origin, their isotopic niches were surprisingly similar within a particular period, although sites of residence were distant. However, niche characteristics differed markedly between breeding and non-breeding periods, indicating a consistent seasonal isotopic niche shift in the sampled populations. Although nightingales of distinct breeding populations migrated to different non-breeding areas, they chose similar foraging conditions within specific periods. However, nightingales clearly changed resource use between breeding and non-breeding periods, indicating adaptations to changes in food availability.     

REPORT ON THE CAPE BIRD CLUB VLEI COUNTS, 1952–58

Meyburg, B.-U., Mendelsohn, J. M., Ellis, D. H., Smith, D.G., Meyburg, C. &; Kemp, A.C. 1995. Year-round movements of a Wahlberg's Eagle Aquila wahlbergi tracked by satellite. Ostrich 66: 135–140.

An adult female Wahlberg's Eagle from northern Namibia was tracked by satellite over a total distance of 8816 km and located 104 times between 11 February and 4 November 1994. It migrated on an almost due north heading to northern Cameroon, north-eastern Nigeria and western Chad through the rain forest belt of the Congo and Zaire after the breeding season. The total trans-equatorial distance between the breeding and non-breeding ranges was 3520 km. During the non-breeding season the bird ranged over a large area (ca. 60 000 km') for about six weeks (29 April – 14 June) in these three countries in a rather nomadic pattern covering a minimum distance of 1256 km. During two further months (14 June – 14 August) it restricted its movements to an area of about 5000 km² near Maiduguri in the Sudan savannah of north-eastern Nigeria. The return migration took about two weeks longer than that to the north, which took about a month.     

Home range and habitat use by the serotine bat, Eptesicus serotinus, in England

Serotine nursery roosts with less than 20 bats were found to have home ranges of at least 24 to 77 km² and core areas of activity from 13 to 33 km². The size of the range may have increased further if more individuals had been tracked, as three of the four colonies studied had not reached their asymptotes. The total home-range area covered by four serotine colonies was 127.36 km². Excluding non-breeding bats, a density of one bat per 120 ha was estimated. However, actual density was likely to be higher if there were additional non-breeding females and immatures that were not in nursery roosts. Colonial home ranges and core areas overlapped, with individuals from different colonies feeding at the same sites. Individual home ranges ( n = 32) varied from 0.16 to 47.58 km², but these were not used exclusively by one individual. Around the colonial core area and breeding roosts, home ranges were used by all individuals from a single colony. It is only further from the core area that ranges appeared to be used by individuals. The distance from roost to feeding areas varied by up to 7.4 km, but the bat usually commuted along lines of trees and hedges and over pastures. This resulted in greater distances being travelled than if they had flown by a direct route. On average, individuals commuted distances of 8 km each night between feeding areas, with a maximum distance of over 41 km. They visited between 0 and 10 feeding sites each night (mean = 2.89).     

The continuing lack of ornithological research capacity in almost all of West Africa

West Africa has high bird diversity and is a crucial non-breeding area for over one-third of European breeding species, yet local capacity for ornithological research and so targeted bird conservation is perceived to be limited. I reviewed all the published literature on the Web of Science^? classified as ‘ornithology’ with an accompanying keyword of a country’s name, over the last three decades, from the 16 countries within West Africa and compared it with that from 16 Western European countries. Inclusion of the country’s name as a search term identified any papers produced by local authors, and so should provide an index of local ornithological capacity. Overall only 129 papers were produced from 1987 to 2016 with West African authors (range: zero Burkina Faso to 45 Nigeria), significantly fewer compared with 12 380 with European authors (range: 71 Greece to 2 745 England). The number of papers produced increased significantly at similar rates over the three-decade period in both continents. The number of papers produced by local authors in West Africa and Europe approximately doubled each decade, but variation between countries was large, particularly in West Africa. The results are broadly the same when paper output is adjusted for the population of each country. Of the three West African countries that showed a consistent increase in numbers of locally authored ornithological papers, only Nigeria showed a highly significant increase and this increase was down to a single ornithological research institute established there in 2002. The results confirm that there is little local ornithological capacity in West Africa and this is not changing except in Nigeria, where even a single new research institute can make a significant difference because of the very low baseline.     

Roseate Terns Sterna dougallii on the southeast coast of South Africa: information on moult and migratory status

Determining the migratory status of seabird populations is crucial for addressing conservation concerns. The Roseate Tern Sterna dougallii is considered endangered in South Africa in view of its small breeding population and the threats to eggs and chicks. Earlier works based on capture-recapture data suggest that this population adopts a partial migratory strategy. Updated capture-recapture data were combined with new data on moult and stable isotopes of scapular feathers to determine whether subpopulations could be identified in the South African breeding population. Moult data on 404 individuals failed to identify subpopulations, but two groups were identifiable with the stable isotopes: one group of four individuals exhibiting low carbon and nitrogen stable isotope ratios and a second group (comprising the remaining 152 individuals) with significantly higher ratios. The isotope data suggest that birds from the two groups moulted in different areas. Comparisons with published studies showed that the 152 individuals had likely moulted their scapulars in South African waters, but the moulting area for the remaining four individuals could not be ascertained due to the absence of detailed isoscapes in the southern part of the Mozambique Channel. Further work investigating the genetic differentiation between South African and Madagascan Roseate Terns may bring new insight into the migratory behaviour of the South African population.     

Seasonal climatic niches diverge in migratory birds

Migratory birds occupy different geographical areas during breeding and non-breeding periods, and thus different factors may determine their range limits depending on each season. One such factor is the spatial climatic component of the niche, which is widely used to model species distributions, yet the temporal component is often neglected and is generally assumed to be constant. We tested the hypothesis that the climatic niche is conserved between breeding and non-breeding areas in 355 bird species migrating through Eurasian–African flyways. For this, we performed niche overlap analyses and compared niche differences between sister or phylogenetically closely related species, as well as linking the differences to migratory distances. For more than 80% of the species, there was no or very little overlap between their breeding and non-breeding climatic niches. For most closely related species, the degree of overlap of their breeding climatic niches was larger than the overlap observed within each species, but not for their wintering climatic niches, suggesting a phylogenetic conservation of breeding climatic niches. Finally, there was a clear negative relationship between migratory distances and climatic niche overlap within each species. Our results confirmed that the climatic niche of most Eurasian–African migratory species differs between both breeding and non-breeding ranges, suggesting distinctive seasonal climatic requirements. Given these results and the geographically uneven effects of climate change, the impact of global change is likely to have different effects in each seasonal range. Hence, both breeding and non-breeding climatic data need to be considered when using species distribution models.