Premium
RECENT POPULATION TRENDS IN CLIFF‐BREEDING SEABIRDS IN BRITAIN & IRELAND
Author(s) -
STOWE T. J.
Publication year - 1982
Publication title -
ibis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.933
H-Index - 80
eISSN - 1474-919X
pISSN - 0019-1019
DOI - 10.1111/j.1474-919x.1982.tb03794.x
Subject(s) - census , geography , cliff , population , irish , regional variation , ecology , demography , biology , archaeology , linguistics , philosophy , sociology , political science , law
Summary The findings of an annual sample census of four species of cliff‐breeding seabirds at study plots in selected British and Irish colonies are presented. The numbers of Guillemot and, to a lesser degree, Razorbill were found to be increasing significantly at most study plots in north and east Britain. With the exception of one Razorbill study plot in Orkney, the only declines detected in these species were in a few colonies in southwest Wales and west Ireland. The magnitude and direction of changes in Kittiwake numbers at study plots showed much local and regional variation, notably in marked decreases in the majority of study plots in Orkney and increases in northwest Ireland. The few data for Fulmar indicate continuing increases in several areas. The results have shown that the census is capable of measuring accurately changes of small magnitude. The problem of whether study plots can be used to infer colony and population change is discussed and comparison made with the findings of other census work.