Twite, by Chris Knights / BTO
MONITORING | Twite
Twite has been on the Birds of Conservation Concern Red List since 1996.
Monitoring Twite in the UK & beyond The most recent survey of English Twite, published by the RSPB in 2018, compared a 1999 census to one carried out in 2013 and reported a decline of 72% (to approximately 164 pairs). Today there could be fewer than 100 pairs. In this article, Jamie Dunning discusses the monitoring work being carried out on the Twite that still breed in England.
At one time Twite populations were
REFERENCES Dunning, J., Finch, T., Davison, A. & Durrant, K.L. (2020). Population-specific migratory strategies of Twite Linaria flavirostris in Western Europe. Ibis 162: 273–278. Wilkinson, N.I., Eaton, M.A., Colhoun, K. & Drewitt, A.L. (2018). The population status of breeding Twite Linaria flavirostris in the UK in 2013. Bird Study 65: 174–188.
20 – LIFECYCLE
probably fairly numerous, and wellconnected, across Eurasia. During the late Pleistocene, when much of the Eurasian landmass was a homogenous, mammoth-grazed steppe, carved out by retreating glaciers, the climate was mild and the range of the Twite was probably continuous from what is now central Asia into modern Europe. Then, following a new period of glacial advancement, Twite found themselves marooned in what refugia habitat remained. It was this period of great global change which resulted in the distribution we see today; two core population centres, one in central Asia – from Asia Minor, the Himalayan steppe and the Qinghai/Tibetan plateau – and another along Western Europe’s Atlantic seaboard. Twenty-two thousand years later and the Western group finds itself once again separated by loss of otherwise continuous habitat. Where their ancestors lost ground to advancing ice sheets, today’s Twite contend with intensification of upland and coastal farming, development and disturbance. What populations remain in Western Europe are not only isolated
from their Asian cousins but also, to some degree, from each other. This fragmentation could, in time, affect the extent by which these small populations are able to recover from continued decline, as between-group recruitment is reduced (monitoring is particularly important here). As a consequence, by the time the Birds of Conservation Concern lists were published in 1996, Twite was added directly to the Red List and stayed there through three subsequent reassessments. Although this article focusses on the Twite which still breed in England, the species also holds on in small pockets across Western Europe. POPULATION DECLINES
A decade of habitat restoration in the uplands appears to have so far failed to halt declines, and emerging evidence points to reduced survival in those English birds which winter on the coast (away from the feeding stations), suggesting a reduction in winter food availability. Twite once bred from the Pennines in the north-west as far south as the East Midlands, and then in small numbers on the moorlands of the south-west. They were probably always Winter 2020
