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We thank the A.P. Leventis Conservation Foundation for supporting this work. Female song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition. Publisher PDF

Aim : To show how recent declines in populations of long-distance migrant birds are associated with recent increases in human population growth and agricultural intensification on their tropical non-breeding grounds, except for synanthropic species, where we expect the reverse. Location : Breeding populations throughout Europe and North America spending the non-breeding season throughout Africa, and Central and South America, respectively. Methods : We mapped 50 species of long-distance migrant birds from published tagging studies of 126 breeding populations and identified their breeding population trends from 2000-2015 from published Country or State census data. We then matched individual bird non-breeding locations, from each population, to local human population change and crop yield data. We used GLMs to predict whether bird population decline was associated with human population change or crop yield and whether this was dependent on if a species was synanthropic or not, controlling for absolute human population density, breeding and non-breeding location, migratory distance and phylogeny. We predicted that bird populations that spend the non-breeding season in areas of recent higher human population increase or agricultural intensification (crop yield), would show greater declines, but that declines would be less for species that frequently utilize anthropogenic habitats such as secondary woodland and farmland. Results : Bird population change, even for synanthropic species, showed a significant negative relationship with relative human population change and crop yield (but this was weak

Long-distance migratory bird populations are likely to be declining because of climate change shifting habitats or anthropogenic habitat loss [1], but this may be mediated by the size of the non-breeding area over which a population spreads (migratory spread), and migration distance (or number of stop-over sites). High migratory spread may make populations more resilient to climate change because they already encompass shifting habitats, but less resilient to uneven habitat loss that may not affect populations with low migratory spread [2] (Figure 1C). As migration distance increases so the probability of encountering a stop-over site with negative environmental change increases [3] (Figure 1D). Consequently, if habitat shift through climate change is the main driver of declines we predict more positive population trends for high spread migrants, but the reverse for outright habitat loss (Figure 1E); we also predict negative population trends for longer distance migrants (Figure 1F). But these relationships may vary between flyways, which differ profoundly in their climate variation, human population change and geography. Here we show that climate change may be more important in Neotropic migrant population declines whereas habitat loss may be more important in the Afro-Palearctic. Postprint