2002-03 pilot Winter Gull Roost Survey (including preliminary details of 2003-04 full Winter Gull Roost Survey) /
Austin, G. E.
British Trust for Ornithology.
Thetford : British Trust for Ornithology,
2003.
"Report of work carried out by the British Trust for Ornithology funded by English Nature, the Department for the Environment (Northern Ireland), the Joint Nature Conservation Committee, Northumbrian Water Ltd and Scottish Natural Heritage; August 2003" -- t.p.
Includes bibliographical references.
Gulls