Words: Kate Risely, of the British Trust for Ornithology (BTO)
This migratory relative of the Stonechat has been on a downward trend for many years, beset by changing conditions both here in the UK and, presumably, on its wintering grounds.Whinchats breed in rough grassland and scrubby gorse, habitat that was previously widespread in this country – however, over the past hundred years, much of the rough scrub in lowland parts of the UK has been removed, tidied or built over, pushing Whinchats to upland areas.
Their strongholds are now in Wales and Scotland, but numbers have continued to fall, even in the remaining suitable habitat, by 57% from 1995 to 2008, and then by 48% (of the 2008 figure) between 2008 and 2009.
Unlike its more familiar (and increasing) relative, the Stonechat, Whinchats are sub-Saharan migrants, wintering in tropical Africa. Many African migrants are showing acute declines, including species as diverse in their UK breeding habits as Turtle Dove, Cuckoo, Yellow Wagtail, Wood Warbler and Nightingale, as well as Whinchat – so it is reasonable to surmise that the conditions on their wintering grounds, or on migration, are contributing to the declines in breeding numbers.
Winter fieldwork carried out by BTO and RSPB staff in Ghana and Burkina Faso aims to understand how migrant birds use the different vegetation zones found in West Africa, and how habitat changes in these areas may have impacted on birds in their wintering grounds. A number of Whinchats were recorded last winter, with sightings in southern and central Ghana, and further work may reveal whether numbers have been affected by habitat changes in Africa.
Back in the UK, BTO researchers have started work on a separate project on the Whinchats of Salisbury Plain. Much of Salisbury Plain has been set aside for military training since the mid 19th century, and has consequently escaped intensive post-war arable farming.
Whinchats have continued to thrive in the area, unlike in much of England. This intensive study involves ringing Whinchats to identify individuals, and finding the nests to monitor nesting success and habitat choice.
This site provides the ideal opportunity to disentangle the factors affecting Whinchat populations – identification of individuals could indicate whether fewer adult birds are returning from Africa each year to replenish the breeding population, and lessons could also be learned from close study of the habitat requirements of this successful breeding population.
Whatever the causes of the decline, they are not limited to the UK. European bird trends show that Whinchat numbers have fallen by 55% across Europe since 1982 – perhaps mainly due to agricultural intensification, but this decline could also point to problems on the shared wintering grounds of birds from different European breeding areas.
By the time you read this article, Whinchats will be starting to leave the country, including adult birds after a (hopefully) successful breeding season, and young birds heading off on their first migration.
The number of Whinchats reported to BirdTrack increases dramatically at this time of year, and from the percentage of submissions that contain this species, we can get a handle on whether numbers leaving the country are higher or lower than normal each year – yet another tool that can be used to build our knowledge of the disappearing Whinchat.