Migratory animals are threatened by human-induced global change. However, little is known about how stopover habitat, essential for refuelling during migration, affects the population dynamics of migratory species. Using 20 years of continent-wide citizen science data, we assess population trends of ten shorebird taxa that refuel on Yellow Sea tidal mudflats, a threatened ecosystem that has shrunk by >65% in recent decades. Seven of the taxa declined at rates of up to 8% per year. Taxa with the greatest reliance on the Yellow Sea as a stopover site showed the greatest declines, whereas those that stop primarily in other regions had slowly declining or stable populations. Decline rate was unaffected by shared evolutionary history among taxa and was not predicted by migration distance, breeding range size, non-breeding location, generation time or body size. These results suggest that changes in stopover habitat can severely limit migratory populations.

Bergmann’s and Allen’s rules state that endotherms should be larger and have shorter appendages in cooler climates. However, the drivers of these rules are not clear. Both rules could be explained by adaptation for improved thermoregulation, including plastic responses to temperature in early life. Non-thermal explanations are also plausible as climate impacts other factors that influence size and shape, including starvation risk, predation risk, and foraging ecology. We assess the potential drivers of Bergmann’s and Allen’s rules in 30 shorebird species using extensive field data (>200,000 observations). We show birds in hot, tropical northern Australia have longer bills and smaller bodies than conspecifics in temperate, southern Australia, conforming with both ecogeographical rules. This pattern is consistent across ecologically diverse species, including migratory birds that spend early life in the Arctic. Our findings best support the hypothesis that thermoregulatory adaptation to warm climates drives latitudinal patterns in shorebird size and shape.

The British population of the Eurasian Otter Lutra lutra has shown a serious decline since 1957-1958. In England the surviving population is broken into small fragments which may not be viable. One way to strengthen the population to enable it to recover would be to insert breeding units into the gaps. A practical methodology using captive-bred Otters in groups of three is described. This was tested successfully in 1983-1985 in East Anglia, with the first two release groups now breeding. The male in the 1983 group was tracked using a radio harness to be sure of survival and to monitor behaviour and use the environment. Data were obtained on the development of a home range in the new environment. Also, useful information was gathered on swimming and hunting speeds, time of emergence, distance travelled each night, activity periods and time spent in each habitat. This behaviour is compared to that of previously tracked wild Otters in Scotland. The very close similarity of many features is encouraging and results may be taken as indicative of the behaviour of wild Otters in lowland Britain.

Tagging is essential for many types of ecological and behavioural studies, and it is generally assumed that it does not affect the fitness of the individuals being examined. However, the tagging of birds has been shown to have negative effects on some aspects of their lives. Here we investigate the influence of tagging on apparent survival. We examined the effects of flipper bands and injected transponders on the apparent survival of adult Little Penguins by comparing the survival probabilities of 2483 Little Penguins marked at Phillip Island, Australia, between 1995 and 2001 in one of three ways: with bands, with transponders or with both. The design of the study and our method of analysis allowed us to estimate tag loss and ensured that tag loss did not bias the survival estimates. Birds marked with flipper bands had lower survival probabilities than those marked with transponders (with apparent survival probabilities in the first year after tagging of 75% for banded birds and 80% for birds fitted with transponders, and in subsequent years of 87% for banded birds and 91% for birds fitted with transponders). We estimated both band and transponder loss probabilities for the first time, and found that transponder loss probabilities were substantially higher than band loss probabilities, particularly in the first year after marking when the tag loss probability was 5% for transponders and 0.7% for bands. Survival probabilities were lower in the first year after marking than in subsequent years for all birds. Studies of penguins that have used flipper bands to identify individuals may have underestimated annual adult survival probabilities, as banded penguins were likely to have lower than average survival probabilities than those of unbanded birds. The higher annual survival probabilities of individuals marked with transponders indicate that this should be the preferred marking technique for Little Penguins. However, future studies will, like ours, need to consider the higher rates of transponder loss when estimating survival, possibly by double-tagging some birds.

The persistence of many cavity‐nesting animals is threatened by habitat modification and a shortage of suitable breeding sites. Consequently, provision of alternative breeding sites is a frequently applied short‐ to medium‐term conservation action. However, the effectiveness of provisioning for breeding success and persistence of breeding animals is rarely considered and could lead populations into an ecological trap. We evaluated the effectiveness of providing nest boxes for little penguins (Eudyptula minor) compared with natural nests over 25 years. We assessed nest‐box adoption and occupancy rates, compared breeding success (i.e., hatching and fledging success) and indices of productivity (i.e., observed brood size, total fledged chick mass, and the number of clutch initiations) with nest survival models and log‐linear mixed effects models, and compared long‐term residency patterns with Link–Barker mark‐recapture models between artificial and natural nests. Little penguins readily adopted nest boxes and breeding attempts were recorded in about 92% of nest boxes installed for 7 or more years. Breeding productivity from 6,081 monitored clutches varied by year and was similar across nest types in most years, but in poor breeding seasons nest boxes performed better. Survival rates to hatching and fledging averaged 7.6% and 8.6% greater in nest boxes, respectively. Similarly, the average total observed mass of chicks produced per clutch was 11% heavier in nest boxes. Annual site fidelity of 2,331 breeding penguins was similar in areas with nest boxes and areas with natural burrows, despite an average of 35% of natural burrows collapsing each year. Nest‐box provisioning for little penguins overcomes local nest‐site limitation, improves breeding success, and can result in local population increases, so is not indicative of an ecological trap. However, a self‐sustaining local population in the long term will require management strategies that address the underlying processes inhibiting population recovery and assist the transition from artificial nest sites back to natural nest sites. © 2014 The Wildlife Society.