Search

We thank the A.P. Leventis Conservation Foundation for supporting this work. One possible hypothesis for the function of post-fledging dispersal is to locate a suitable future breeding area. This post-fledging period may be particularly important in migratory species because they have a limited period to gather information prior to autumn migration, and in protandrous species, males must quickly acquire a territory after returning from spring migration to maximize their fitness. Here we use color-ring resightings to investigate how the post-fledging dispersal movements of the Cyprus wheatear Oenanthe cypriaca, a small migratory passerine, relate to their first breeding territory the following year when they return from migration. We found that males established first breeding territories that were significantly closer to their post-fledging location than to their natal sites or to post-fledging locations of other conspecifics, but these patterns were not apparent in females. Our findings suggest that familiarity with potential breeding sites may be important for juveniles of migratory species, particularly for the sex that acquires and advertises breeding territories. Exploratory dispersal prior to a migrant’s first autumn migration may contribute toward its breeding success the following year, further highlighting the importance of early seasonal breeding on fitness and population dynamics more generally. Publisher PDF

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

Dispersal to efficiently locate future breeding areas in young animals has important consequences for survival, life history and future breeding success, and therefore population dynamics and evolution. Long-distance migrant birds that have little time immediately pre-breeding may use the post-fledging period to locate their future breeding territory. We radio-tracked 37 juvenile Cyprus Wheatears, Oenanthe cypriaca, a long-distance migrant passerine, to investigate movements for 10 weeks post-fledging. We measured how distance from the nest and distance of consecutive movements changed with age. We tested whether distance from the nest stopped increasing and consecutive movement distance became similar to pre-dispersal distances, consistent with a fledgling adopting a post-fledgling home range that could reflect scoping out a future local breeding territory. Fledglings had a very high survival rate. Directed movements away from the natal territory started at about 18 days until about 45 days when individuals adopted a more fixed location on average about 600 m (range 0–1500) from their natal site, and further movements were at a scale equivalent to movements within an adult-sized breeding territory. Our results suggest dispersal followed by settlement in a fixed home range prior to first migration that could function to identify the breeding site location for the following year.

Funding: AP Leventis Conservation Foundation. Migrating animals should optimise time and energy use when migrating, travelling directly to their destination. Detours from the most direct route may arise however because of barriers and weather conditions. Identifying how such situations arise from variable weather conditions is crucial to understand population response in the light of increased anthropogenic climate change. Here we used light-level geolocators to follow Cyprus wheatears for their full annual cycle in two separate years migrating between Cyprus, over the Mediterranean and the Sahara to winter in north-east sub-Saharan Africa. We predicted that any route detours would be related to wind conditions experienced during migration. We found that spring migration for all birds included an eastern detour, whilst autumn migrations were direct across the Sahara. The direct autumn migration was likely a consequence of consistent tail-winds, whilst the eastern detour in spring is likely to be more efficient given the wind conditions which are against a direct route. Such variable migration routes shaped by coincidence with prevailing winds are probably common suggesting that some birds may be able to adapt to future changes in wind conditions. 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

Estimating the pollen-deposition effectiveness of flower visitors is fundamental to understanding their performance as pollinators. While estimates of visitation rates, pollen loads, and single visit deposition (SVD) are all useful proxies for performance, and so help to reveal the relative effectiveness of different visitors, none take into account the breeding system of the plants, or the quality of pollen deposited. Here we compare the performance of visitors to the self-incompatible plant Brassica rapa (turnip) using SVD and pollen germination. We also report the first use of the staining of Brassica rapa stigma papilla cells (known to reveal a specific reaction to self-pollen) to compare self-pollen deposition between insect visitors. We found that most of the pollen grains deposited by insect visitors (and therefore counted by SVD methods) were non-germinating self-pollen. A smaller proportion of grains were outcrossed and so germinated. There was also a significant positive relationship between environmental conditions (wind speed) and pollen deposition, but not pollen germination. Both methods identified Bombus spp . as the best-performing visitors on turnip flowers, followed by Eristalis spp ., whereas performance estimates for Episyrphus balteatus and ‘other hoverflies’ were no higher than controls for both methods. This study provides further insight into the methodology for estimating pollinator performance, especially in plants when only cross-pollen can germinate. NOTE: Supplementary data to this article can be found in the left menu!

Observations are key to understand the drivers of biodiversity loss, and the impacts on ecosystem services and ultimately on people. Many EU policies and initiatives demand unbiased, integrated and regularly updated biodiversity and ecosystem service data. However, efforts to monitor biodiversity are spatially and temporally fragmented, taxonomically biased, and lack integration in Europe. EuropaBON aims to bridge this gap by designing an EU-wide framework for monitoring biodiversity and ecosystem services. EuropaBON harnesses the power of modelling essential variables to integrate different reporting streams, data sources, and monitoring schemes. These essential variables provide consistent knowledge about multiple dimensions of biodiversity change across space and time. They can then be analyzed and synthesized to support decision-making at different spatial scales, from the sub-national to the European scale, through the production of indicators and scenarios. To develop essential biodiversity and ecosystem variables workflows that are policy relevant, EuropaBON is built around stakeholder engagement and knowledge exchange (WP2). EuropaBON will work with stakeholders to identify user and policy needs for biodiversity monitoring and investigate the feasibility of setting up a center to coordinate monitoring activities across Europe (WP2). Together with stakeholders, EuropaBON will assess current monitoring efforts to identify gaps, data and workflow bottlenecks, and analyse cost-effectiveness of different schemes (WP3). This will be used to co-design improved monitoring schemes using novel technologies to become more representative temporally, spatially and taxonomically, delivering multiple benefits to users and society (WP4). Finally, EuropaBON will demonstrate in a set of showcases how workflows tailored to the Birds Directive, Habitats Directive, Water Framework Directive, Climate and Restoration Policy, and the Bioeconomy Strategy, can be implemented (WP5).