The measurement of stable hydrogen isotope ratios (δ2H) in animal tissues is a popular means of inferring spatial origins and migratory connections. However, the use of this isotope to infer diet and potentially trophic position remains poorly understood, especially in non-aquatic terrestrial ecosystems. In many animal communities, tissue δ15N values are strongly associated with trophic position. Correlations between tissue δ2H and δ15N are expected, then, if δ2H is affected by trophic enrichment of 2H. In addition, within sites, we would expect higher tissue δ2H values in insectivorous species compared to granivores or nectarivores. We tested these hypotheses for two resident avian communities in Nigeria consisting of 30 species representing a range of dietary guilds (granivores, frugivores, nectarivores, omnivores, insectivores) by comparing feather δ2H, δ15N and δ13C values. We found considerable isotopic overlap among all guilds except granivores, with no clear pattern of enrichment in 2H with trophic position. However, at one of our sites (open scrubland), feather δ2H was positively correlated with feather δ15N (R2 = 0.30) compared to a closed canopy forest site (R2 = 0.09). Our results indicate weak evidence for predictable trophic enrichment in 2H in terrestrial environments and indicate that controlled studies are now required to definitively elucidate the behavior of H isotopes in terrestrial food webs.

The Oriental white stork (Ciconia boyciana), with a global population of roughly 2500, is listed as endangered by IUCN. To date, little is known about its behaviors, particularly on migration, habitat use and their ontogenic differences. In this study, we tracked 11 Oriental White storks (9 juveniles and 2 adults) rescued in Sanjiang Plain and investigated their migration behaviors and survival rates using GPS/GSM telemetry. The results show that all the rescued individuals joined the wild migrating groups, but the migration routes of juvenile birds are highly variable compared to adult ones. From its breeding grounds of the Songnen/Sanjiang Plains to the wintering grounds in middle reaches of the Yangtze River, there is no significant correlation in habitat selections by adult birds, as wetlands being their first choice. In contrast, a positive correlation in juveniles' selection has been identified over artificial habitats such as rice paddies and fish farms,which could lead to human-wild conflicts and affect the survival of juvenile storks. In this study, eight out of nine juveniles dies in the end of tracking. Our study exposes negative consequences of inappropriate release of rescued wild animals (especially juveniles) on species survival, and thus provides scientific guidelines to the future situations alike. Moreover, it is necessary to reduce the direct contact between humans and rescued animals, so that their dependence on artificial environments could be reduced, which could benefit the species' long term survival, especially for the rescued population.

The European hedgehog population is declining in Europe. It is therefore important to investigate the causes for the decline and monitor the general health of the species. We investigated the endoparasite occurrence in 299 dead European hedgehogs. Of these, endoparasites were detected in 69% of the individuals tested. We identified Crenosoma striatum, Capillaria aerophila (syn. Eucoleus aerophilus), Capillaria spp., coccidia, Cryptosporidium spp., Brachylaemus spp. and Capillaria hepatica. We also examined the hedgehogs for Giardia spp. and Echinococcus multilocularis but all were negative. Coccidia (n = 7, 2.5%) and Cryptosporidium spp. (n = 14, 5.2%) were only detected in individuals from Zealand, Lolland and Jutland south of the Limfjord. Single cases of Brachylaemus spp. (n = 1, 0.4%) and Capillaria hepatica (n = 1, 1.1%) were exclusively discovered in Jutland south and north of the Limfjord, respectively. These results indicate a regional difference in endoparasite species carried by European hedgehogs in Denmark. This stresses the need for hedgehogs to be cared for locally when admitted to wildlife rehabilitation centres, and to be released within their area of origin, to prevent spread of endoparasite infections among hedgehogs. Additionally, we explored the following possible determinants of parasite infection in the hedgehogs: sex, age, mortality category (in-care, natural and roadkill), infection with MRSA, genetic heterozygosity, month of death, geographical location and habitat type, and found that only age had a statistically significant effect on endoparasite prevalence, as we detected a lower occurrence of endoparasites in juvenile hedgehogs (<1 year) compared to the other age classes. However, pairwise comparisons of geographical regions did show significant differences in endoparasite occurrence: Zealand vs. Jutland south of the Limfjord and Zealand vs. Falster. We conclude that, in line with previous studies of European hedgehogs throughout their range in Western Europe, endoparasite infections are common and a natural part of their ecology.

OBJECTIVES:A recent study from Sweden showed that European hedgehogs may constitute a reservoir for methicillin-resistant Staphylococcus aureus (MRSA), but this host-parasite relationship remains to be investigated in other countries. In this study, we therefore sought to: 1) determine the dissemination of MRSA in European hedgehogs throughout Denmark; 2) investigate determinants of MRSA carriage in hedgehogs; 3) determine the potential for zoonotic transmission of MRSA from hedgehogs to humans; and 4) characterise the detected MRSA on both a phenotypic and molecular level.METHODS:Nasal swabs were taken from 188 dead hedgehogs collected by volunteers throughout Denmark to determine the occurrence of MRSA. Additionally, 16 hedgehog rehabilitators were tested for potential zoonotic transmission of MRSA from hedgehogs to humans. The swabs were incubated in tryptic soy broth supplemented with 6.5% NaCl, followed by spread of 10 μl on Brilliance MRSA 2 agar. One presumptive MRSA colony from each plate was subcultured on 5% blood agar. All S. aureus subcultures were verified by a PCR assay detecting mecA, mecC, lukF-PV, scn, and spa, followed by spa typing.RESULTS:A total of 114 (61%) hedgehogs carried mecC-MRSA, whereas none carried mecA-MRSA. The detected mecC-MRSA belonged to two genetic lineages CC130 (spa-types: t528, t843, t1048, t3256, t3570, t6220, t17133) and CC1943 (spa-types: t978, t2345, t3391, t8835, t16868), 52% of which were spa-type t843 (CC130).The detection rate of mecC-MRSA in the hedgehogs was similar regardless of cause of death, sex, region and habitat type. None of the hedgehog rehabilitators carried MRSA.CONCLUSIONS:This nationwide study confirms a high occurrence of mecC-MRSA in hedgehogs, which could serve as a natural reservoir for this specific type of MRSA. Furthermore, our study did not find signs of zoonotic transmission of mecC-MRSA to hedgehog rehabilitators.

The annual cycle of migrating birds is shaped by their seasonal movements between breeding and non-breeding sites. Studying how migratory populations are linked throughout the annual cycle—migratory connectivity, is crucial to understanding the population dynamics of migrating bird species. This requires the consideration not only of spatial scales as has been the main focus to date but also of temporal scales: only when both aspects are taken into account, the degree of migratory connectivity can be properly defined. We investigated the migration behaviour of hoopoes (Upupa epops) from four breeding populations across Europe and characterised migration routes to and from the breeding grounds, location of non-breeding sites and the timing of key migration events. Migration behaviour was found to vary both within and amongst populations, and even though the spatial migratory connectivity amongst the populations was weak, temporal connectivity was strong with differences in timing amongst populations, but consistent timing within populations. The combination of diverse migration routes within populations and co-occurrence on the non-breeding grounds between populations might promote exchange between breeding populations. As a result, it might make hoopoes and other migrating bird species with similar strategies more resilient to future habitat or climatic changes and stabilise population trends.

Birds exhibit a wide variety of migration strategies, not only between species, but also within species. Populations might migrate to specific sites outside of the breeding season, but individuals within populations may also exhibit different migration strategies. Young, unexperienced birds may take different routes, visit different sites, and time their annual cycle differently than adults. In turn, within groups of adult birds, there may be a division between the sexes whereby males and females migrate to different sites or, more commonly, at different times. We investigated differences in the migration strategies of male and female ospreys (Pandion haliaetus) from a breeding population in northeastern Germany. An important difference between the sexes was the much earlier leaving of the breeding place by the females compared to the males. The difference in the timing of departure was much more pronounced compared to most other raptor species. The other main difference between the male and female ospreys was the distance that the birds accumulated over the annual cycle, with males generally moving more while at the breeding ground compared with the non-breeding grounds, and the opposite in females. An exception to this observation was two males that migrated to the Iberian Peninsula, that covered longer distances during the non-breeding season. Consequently, individuals accumulated the same distances over the course of an annual cycle, regardless of sex or migration strategy. Unexpectedly, a difference in the timing of the annual cycle between the sexes occurred at the breeding grounds with females leaving 2 to 3 months before the males, long before the young had fledged. Because males migrated much faster and, unlike the females, did not make prolonged stops, their arrival times at the non-breeding grounds were not different. Return migration to the breeding grounds was very similar between the sexes, and even the two males that spent the non-breeding season on the Iberian Peninsula did not arrive before any of the other birds. Thus, a shorter migration distance is not necessarily associated with an advantage with respect to a timely return to the breeding grounds.

German Ospreys (Pandion haliaetus) were thought to migrate to sub-Saharan Africa. However, most of the many ring recoveries were from juvenile birds, and adults had never been satellite-tracked. During 1995–2011 we marked 28 adult Ospreys in NE-Germany with satellite tags working up to eight years.

In migrant animals, conditions encountered at various times and places throughout their annual cycle may affect breeding success. Yet, most studies so far have only investigated the effect of specific parts of the annual cycle, despite the importance to understand how different stages can interact and how these stages compare to intrinsic quality to properly modulate breeding success. Using a structural equation modelling approach, we investigated drivers of breeding success (migration cycle, individual quality, breeding conditions) in hoopoes Upupa epops, a long-distant migrant. Our causal framework explained 75% of the variation in breeding success. The effect of the migration schedule was negligible, whereas the previous breeding attempt strongly influenced current breeding success. We suggest that the interplay of individual quality and environmental conditions during both previous and current breeding season may be more important drivers of breeding success than migration schedules, even in a long-distance migrant. We conclude that structural equation modeling is a promising tool to investigate causal relationships. Applied to hoopoes, we demonstrated that current breeding success is strongly linked to previous breeding success. Complementary analysis integrating weather and climate conditions during migration and the breeding season may provide a deeper and wider overview of the annual cycle of hoopoes and additional insights into the existence of carry-over effects in breeding success.

The Hoopoe (Upupa epops epops) breeds widely in Eurasia and most populations migrate to Africa during the boreal winter. To date, data regarding its phylogeography in Europe are missing. In this study, we investigated the phylogeography and population genetics of Hoopoes by means of mitochondrial DNA (mtDNA) sequencing as well as microsatellite genotyping. Our analyses revealed 32 haplotypes in the cytochrome c oxidase subunit I (COI) (269 individuals) and 50 haplotypes in cytochrome b (cyt b) (233 individuals). Analyses of mtDNA clearly demonstrated that the bulk of variance (98.23%) could be attributed to inner-population variance. Thus, the low frequency single nucleotide substitutions resulted in "star-like" haplotype networks without define geographical structure. Hoopoes clearly experienced a bottleneck followed by sudden expansion, as was also apparent from tests on the unimodal mismatch, Bayesian skyline plot, significant negative neutrality tests as well as bottleneck signals. These tests pointed to strong demographic fluctuations in the hoopoe populations. GENELAND, DAPC and STRUCTURE analyses of microsatellites along with their corresponding Fst values suggested that current genetic restriction separates birds from Armenia from the remaining populations. Except for hoopoes from Armenia, all the European populations exhibited an admixed phylogeographic pattern. We conclude that this genetic panmixia might be a consequence of a combination of historical events (e.g. repeated colonizations and retreatments from northern habitats during the Pleistocene and a sudden postglacial expansion) and current processes (e.g. long-distance migration, immigration or population recruitments).

Migrating birds have to incorporate migration into their annual cycle, next to breeding and moult. This presents the challenge to arrive at the right place at the right time at any given moment during the year to maximize fitness. Although many studies have investigated the timing of specific (life-history) activities of migrating birds, it is poorly studied how the timing and duration of these activities depend on each other and, ultimately, how they affect fitness. Therefore, we investigated variability and dependencies in the timing and duration of successive activities throughout the annual cycle and assessed their fitness consequences in hoopoes (Upupa epops), a long-distance migratory bird, using geolocator and breeding phenology data of five consecutive years. We found that the timing and duration of seasonal activities generally depended on the timing and duration of the preceding activity; yet, the strength of these dependencies and the degree of variability varied between activities. The strongest dependencies were found between the end of breeding and departure from the breeding grounds as well as between the arrival in the breeding grounds and the onset of breeding. We also found fitness consequences of timing and duration but only for specific activities: spring migration and particularly the duration of the pre-breeding period influenced the quality of the territory acquired as well as the total number of fledglings. Consequently, we suggest that our study species has the flexibility to adjust the timing and duration of activities but to varying degrees. This is a step forward in understanding the time-constraints that migratory animals face and in identifying their fitness consequences.

In most bird species, all feathers are moulted at least once per year, usually after breeding (complete post-breeding moult). Woodpeckers (Picidae) often retain some primary coverts and secondaries during their otherwise complete post-breeding moult. To date, this phenomenon has received little attention and has not been studied thoroughly in European woodpeckers, even though it could prove very helpful for ageing and therefore for demographic studies. We studied the moult patterns of breeding adult Wrynecks Jynx torquilla in a Swiss Alpine valley between 2013 and 2016. Due to intensive ringing in the study area prior to the current study, our data set included birds of known age. Some individuals were captured and their moult documented in up to four years in a row. We found that Wrynecks present an extreme case of delayed primary-covert moult. No primary covert (PC) was renewed during the post-juvenile moult. At most three PCs were renewed by the second post-breeding moult and three to six at more advanced ages. That some juvenile PCs were retained until the sixth calendar year has not previously been documented for a species with such a relatively short lifespan. This principle of 'postponed moult' in Wrynecks affects the appearance of the PCs differently in each age class and allows us to age birds more accurately than previous methods. Here we describe how to interpret the moult pattern of PCs to age Wrynecks properly and argue that the moult strategy of Wrynecks was hitherto incompletely and in many cases mistakenly understood, leading to confusion in the ageing of Wrynecks.

Tracking devices are used in a broad range of species for a broad range of questions, but their potential effects on study species are debated. Outcomes of earlier studies on effects are equivocal: some studies find negative effects on behaviour and life history traits, while others do not. Contrasting results might be due to low sample sizes, temporal scale (no repetition of the study over multiple years) and a limited range of response variables considered. We investigated effects of geolocators on a range of response variables: body condition, physiological states, reproductive performance and, ultimately, annual apparent survival for a medium-sized Palaearctic-African long-distance migrant, the Eurasian Hoopoe Upupa epops, for the combined study period (2009–2014) and for individual years. We investigated response variables 1 year after deployment of the geolocator and found no differences in body condition, physiological states and several components of reproductive performance between individuals with and without geolocators when data were combined. Also, apparent annual survival did not differ between geolocator and control birds. We did, however, find effects in some years possibly related to environmental stochasticity or chance events due to lower sample sizes. We argue that results of studies on the effects of tracking devices should be interpreted and generalized with great caution and suggest that future studies on the effects of tracking devices are conducted over multiple years. Future studies should also apply capture–recapture models to estimate survival, rather than focus solely on return rates.

AbstractMigratory birds are often faithful to wintering (nonbreeding) sites, and also migration timing is usually remarkably consistent, that is, highly repeatable. Spatiotemporal repeatability can be of advantage for multiple reasons, including familiarity with local resources and predators as well as avoiding the costs of finding a new place, for example, nesting grounds. However, when the environment is variable in space and time, variable site selection and timing might be more rewarding. To date, studies on spatial and temporal repeatability in short‐lived long‐distance migrants are scarce, most notably of first‐time and subsequent migrations. Here, we investigated repeatability in autumn migration directions, wintering sites, and annual migration timing in Hoopoes (Upupa epops), a long‐distance migrant, using repeated tracks of adult and first‐time migrants. Even though autumn migration directions were mostly the same, individual wintering sites often changed from year to year with distances between wintering sites exceeding 1,000 km. The timing of migration was repeatable within an individual during autumn, but not during spring migration. We suggest that Hoopoes respond to variable environmental conditions such as north–south shifts in rainfall during winter and differing onset of the food availability during spring migration.

The Iberian Peninsula is a wintering area for an estimated 300 million birds. Most insectivorous birds winter in the southern half of the Peninsula, where mild mid-winter temperatures ensure the availability of insects. However, case studies of habitat use by specific species during winter are still rare. a species of particular interest is the Eurasian wryneck Jynx torquilla, the only long-distance migratory woodpecker in Europe that feeds almost exclusively on ants. Its European populations have declined throughout Europe over recent decades. Wrynecks are known to winter in the Iberian Peninsula but it has only recently been shown that at least some of these birds originate from Central European breeding populations. Hitherto, the habitats they select in winter have remained unknown although it is plausible to think that they are habitat specific given the birds' strong reliance on ants as their main food source. We studied the wintering habitat selection by wrynecks in northern Extremadura, Spain, with MaxEnt models. We found that they chose diverse, extensive, agricultural (irrigated) croplands. Our findings highlight the importance of these threatened landscapes for wintering birds.

European Wrynecks Jynx torquilla torquilla have generally been considered to be long‐distance P alaearctic–African migrants that spend the non‐breeding season in S ahelian A frica, where they have been reported regularly. Results from tracking individual birds showed that Wrynecks from two C entral E uropean populations migrated only relatively short distances to the I berian P eninsula and northwestern Africa ( c . 1500 km and 3000 km, respectively), compared with a minimum distance of about 4500 km to S ahelian A frica. Additionally, differences in wing lengths of populations from C entral and N orthern Europe support the idea of leap‐frog migration, populations from N orthern Europe being long‐distance migrants with a non‐breeding distribution in S ahelian A frica.

Many migratory herbivores seem to follow the flush of plant growth during migration in order to acquire the most nutrient‐rich plants. This has also been hypothesized for arctic‐breeding geese, but so far no test of this so‐called green wave hypothesis has been performed at the individual level. During four years, a total of 30 greater white‐fronted geese Anser albifrons albifrons was tracked using GPS transmitters, of which 13 yielded complete spring migration tracks. From those birds we defined stopover sites and related the date of arrival at each of these stopovers to temperature sum (growing degree days, GDD), snow cover, accumulated photoperiod and latitude. We found that geese arrived at spring stopovers close to the peak in GDD jerk; the ‘jerk’ is the third derivative, or the rate of change in acceleration, and GDD jerk maxima therefore represent the highest acceleration of daily temperature per site. Day of snow melt also correlated well with the observed arrival of the geese. Factors not closely related to onset of spring, i.e. accumulated photoperiod and latitude, yielded poorer fits. A comparison with published data revealed that the GDD jerk occurs 1–2 weeks earlier than the onset of spring derived from NDVI, and probably represents the very start of spring growth. Our data therefore suggest that white‐fronted geese track the front of the green wave in spring.