Loss of breeding waders from key lowland grassland sites in Northern Ireland

Between the mid-1980s and 2018–2019, Northern Ireland’s lowland wet grasslands saw a 73% decline in their breeding wader populations, from 1,296 to 354 pairs across 74 surveyed sites.

Transatlantic spread of highly pathogenic avian influenza H5N1 by wild birds from Europe to North America in 2021

Highly pathogenic avian influenza was detected in poultry and a free-living gull in Newfoundland and Labrador, Canada, in 2021, raising concerns about the potential for a new outbreak and questions about the likely origins of the virus.

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Urban and coastal breeding lesser black-backed gulls (Larus fuscus) segregate by foraging habitat

A collaboration between BTO, Natural England and University of Exeter researchers has used GPS-tracking technology to compare the movements and habitat use of Lesser Black-backed Gulls breeding at neighbouring coastal and urban colonies in Cumbria, northern England. The study found that the distance birds covered making foraging trips and the size of their 'home ranges' - the area that an individual bird uses on a daily basis during foraging, breeding and roosting activities - differed between the urban and coastal colonies and revealed a marked segregation in habitat choice. 

Breeding ground temperature rises, more than habitat change, are associated with spatially variable population trends in two species of migratory bird

BTO research has examined the effects of climate change and habitat loss on the population trends of Willow Warbler and Chiffchaff. These closely related songbirds, tricky to distinguish by eye, share breeding grounds across the UK but migrate to different wintering grounds. While Chiffchaffs mainly migrate to south-west Europe and north-west Africa, with a small number remaining in the UK, Willow Warblers head across the Sahara to the humid zone in central Africa. 

Relative roles of static and dynamic abiotic conditions as drivers of foraging behaviour in breeding Sandwich Terns

New research involving BTO used GPS tagging to examine Sandwich Tern foraging behaviour during the breeding season. Like other seabirds, Sandwich Terns are so-called ‘central place foragers’ while they are incubating eggs and feeding chicks, shuttling to and from their nest site in search of food. However, successfully finding food on each trip away from the nest requires navigating a continually changing marine environment and relocating moving prey.