New research led by BTO scientists has examined the effect of food supplies on Oystercatchers in Wales, showing how populations are affected by the availability of prey species, and underlining the importance of alternative foraging areas close by. Oystercatcher numbers are declining in the UK, in line with the trends for wader species globally, and with ever greater anthropogenic changes to wader habitats, it is vital we understand the processes driving population change if we are to take effective conservation action. This study used data from the Wetland Bird Survey (WeBS) and ringing to assess the effect of Cockle availability on wintering Osytercatcher numbers in south Wales. Cockles are an important prey species for Oystercatchers and other wader species, leading to competition for this food resource with humans, who commercially fish Cockles and other shellfish. Burry Inlet in south Wales formerly had a highly productive Cockle fishery, but in 2004 numbers crashed, with larger, older Cockles especially affected. Smaller Cockles have since gradually become re-established, but larger Cockle stocks have yet to recover. Burry Inlet is also a Special Protection Area for birds. Following the 2004 crash, the number of Oystercatchers recorded during WeBS counts on Burry Inlet fell, but there was an increase in birds counted in the neighbouring Three Rivers Estuary, part of the Carmarthen Bay Special Area of Conservation, suggesting some Oystercatchers simply moved from one site to the other. Data from ringing also showed an apparent reduction in survival of Oystercatchers using Burry Inlet in years of low Cockle biomass. The fact that Oystercatchers were able to move to a nearby site, where Cockle harvesting had been capped due to regulations associated with the area’s protected status, shows the importance of having resilient networks of protected areas. Such networks can buffer fluctuations in the suitability of individual sites to particular species. The study also underlines the importance of long-term monitoring in accurately understanding the effects of incidents such as the Burry Inlet Cockle crash, allowing for optimal management of both protected area networks and fishery practices.

Research from BTO has investigated the ways in which to optimise long-term GPS tagging in large gulls, so that sufficient data are collected while birds' welfare needs are met.

New research involving BTO suggests that the management of protected areas in Europe can aid wintering waterbirds species in shifting their ranges north as the climate warms.

Breeding waders in Britain are high profile species of conservation concern because of their declining populations and the international significance of some of their populations. Forest expansion is one of the most important, ongoing and large-scale changes in land use that can provide conservation and wider environmental benefits, but also adversely affect populations of breeding waders. We describe models to be used towards the development of tools to guide, inform and minimise conflict between wader conservation and forest expansion. Extensive data on breeding wader occurrence is typically available at spatial scales that are too coarse to best inform waderconservation and forestry stakeholders. Using statistical models (random forest regression trees) we model the predicted relative abundances of 10 species of breeding wader across Britain at 1-km square resolution. Bird data are taken from Bird Atlas 2007–11, which was a joint project between BTO, BirdWatch Ireland and the Scottish Ornithologists’ Club, and modelled with a range of environmental data sets.

Commonly referred to as the UK Red List for birds, this is the fifth review of the status of birds in the UK, Channel Islands and Isle of Man, published in December 2021 as Birds of Conservation Concern 5 (BOCC5). This updates the last assessment in 2015. Using standardised criteria, experts from a range of bird NGOs, including BTO, assessed 245 species with breeding, passage or wintering populations in the UK and assigned each to the Red, Amber or Green Lists of conservation concern. The same group of experts undertook a parallel exercise to assess the extinction risk of all bird species for Great Britain (the geographical area at which all other taxa are assessed) using the criteria and protocols established globally by the International Union for the Conservation of Nature (IUCN). This resulted in the assessment of 235 regularly occurring species (breeding or wintering or both), the total number assessed differing slightly from BOCC5 due to different rules on the inclusion of scarce breeders and colonisation patterns. The results of this second IUCN assessment (IUCN2) are provided in the same paper as BOCC5. Increasingly at risk This update shows that the UK’s bird species are increasingly at risk, with the Red List growing from 67 to 70. Eleven species were Red-listed for the first time, six due to worsening declines in breeding populations (Greenfinch, Swift, House Martin, Ptarmigan, Purple Sandpiper and Montagu’s Harrier), four due to worsening declines in non-breeding wintering populations (Bewick’s Swan, Goldeneye, Smew and Dunlin) and one (Leach’s Storm-petrel) because it is assessed according to IUCN criteria as Globally Vulnerable, and due to evidence of severe declines since 2000 based on new surveys on St Kilda, which holds more than 90% of the UK’s populations. The evidence for the changes in the other species come from the UK’s key monitoring schemes such as BTO/JNCC/RSPB Breeding Bird Survey (BBS) for terrestrial birds, the BTO/RSPB/JNCC Wetland Bird Survey (WeBS) for wintering populations and the Rare Breeding Bird Panel (RBBP) for scarce breeding species such as Purple Sandpiper. The IUCN assessment resulted in 108 (46%) of regularly occurring species being assessed as threatened with extinction in Great Britain, meaning that their population status was classed as Critically Endangered, Endangered, or Vulnerable, as opposed to Near Threatened or of Least Concern. Of those 108 species, 21 were considered Critically Endangered, 41 Endangered and 46 Vulnerable. There is considerable overlap between the lists but unlike the Red List in BOCC5, IUCN2 highlights the vulnerability of some stable but small and hence vulnerable populations as well as declines in species over much shorter recent time periods, as seen for Chaffinch and Swallow.

A new collaborative research study involving BTO has used GPS to track the movements of one of Europe’s rarest birds of prey, the Greater Spotted Eagle, shedding light on the pressures this species faces outside of the breeding season. Supporting our colleagues in Ukraine We have been working with Ukrainian and Belarusian colleagues in Polesia since 2019. We are appalled by Russia's invasion of Ukraine and stand in full support of those affected by this conflict. Our project partner Frankfurt Zoological Society (FZS) has been working to get partners and staff in Ukraine to safety, though most remain on-site, providing refugees with resources and supporting the protected areas’ running costs at a time when other funding has been cut off. We hope that the global support of Ukraine will help bring an end to this appalling conflict, and that we will be able to continue to work with our colleagues to learn about and protect the country’s precious habitats and wildlife. If you would like to make a donation, visit the ZFS fundraising appeal.