Combination of marine and artificial freshwater habitats provides wintering Black-tailed Godwits with landscape supplementation
Résumé
Migratory shorebirds, which have an energy-expensive lifestyle, must replenish their body reserves during winter to ensure their survival. Hence, birds have to select wintering habitats that provide the best net energy gain per unit of time while also considering possible disturbances such as predation risk, competition and resource depletion. Different foraging strategies can therefore emerge between species or individuals, such as focusing on one high-quality foraging habitat or making use of multiple habitats, resulting in contrasting distributions and movements patterns. By analysing the movements of 10 wintering Black-tailed Godwits Limosa limosa islandica through GPS-telemetry, our study aimed to understand and describe their spatiotemporal use of wetlands. Our results show that Black-tailed Godwits are flexible in terms of habitat use. All tracked godwits used more than one site during the survey period, with site shifts at both small and large spatial scales, and used multiple habitat types within sites. Indeed, although a dominant use of intertidal areas was observed, birds showed seasonal and daily habitat shifts by visiting inland marshes, saltpans and hunting ponds, with a habitat-specific activity rhythm. Finally, our results support the importance of the protected areas and the management of artificial wetland habitats to ensure the preservation of high-quality wintering areas for godwits.