File:The Canadian field-naturalist (1973) (20332264448).jpg

Title: The Canadian field-naturalist
Identifier: canadianfieldnat1973otta (find matches)
Year: 1973 (1970s)
Authors: Ottawa Field-Naturalists' Club
Subjects:
Publisher: Ottawa, Ottawa Field-Naturalists' Club
Contributing Library: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library
Digitizing Sponsor: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
1973 Lock and Ross: Cormorant Nests in Nova Scotia 45 possible to make exact population estimates of tree-nesting colonies from the air though colour transparencies allowed some good counts to be made. As many as possible of the colonies were later visited by boat to obtain accurate counts and species identifications. Colony visits were made between May 18 and June 27. Aerial censuses were done on May 28 in Minas Basin and the Bay of Fundy; on May 29 along the north and northeast coasts of mainland Nova Scotia and into Bras D'or Lake; and one June 11 around the southern part of the province. Results and Discussion Breeding Population Size The results of the census are presented in Figure 1 and in Table 1. Abbreviations used are APE meaning aerial photographic estimate; AVE meaning aerial visual estimate; and GC meaning ground count. MNR indicates that in- formation has been taken from a card on the Maritimes Nest Record Scheme. In Table 2 we present some previous censuses of these colo- nies and in Table 3 we hst records for some colonies which have recently disappeared. Thirty colonies of P. auritus were censused, giving a total of approximately 4150 pairs breeding in Nova Scotia. Ten of these colonies had been censused previously and large in- creases are apparent in five of them: Indian I., Boot I., Tobacco I., Double I., and Pictou Wharf. There are also indications of a large increase in the Bald I. colony. Only one colony, Cape Split, seems to have decreased in size re-
Text Appearing After Image:
FiGURE. 1. Colonies of the Great Cormorant (open circles) and the Double-crested Cormorant (closed circles) in Nova Scotia in 1971. Half shaded circles indicate colonies in which both species breed.

Note About Images