Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Animal Sciences

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

1997

Black-crowned night-heron

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

A Geographic Information System To Monitor Nest Distributions Of Double-Crested Cormorants And Black-Crowned Night-Herons At Shared Colony Sites Near Toronto, Canada, S. Jarvie, H. Blokpoel, T. Chipperfield Dec 1997

A Geographic Information System To Monitor Nest Distributions Of Double-Crested Cormorants And Black-Crowned Night-Herons At Shared Colony Sites Near Toronto, Canada, S. Jarvie, H. Blokpoel, T. Chipperfield

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

In the early 1990’s, it became apparent that the rapid colonization of Tommy Thompson Park on Lake Ontario near Toronto by double-crested cormorants (Phalacrocorax auritus) would eventually affect the existing colonies of blackcrowned night-herons (Nycticorax nycticorax) owing to competition for nest sites and destruction of nest trees. As a result, monitoring of these two species was expanded in 1992 by individually marking all nest trees (using permanent metal tree tags) and by recording the numbers of heron and cormorant nests for all nest trees. In 1996, professional surveyors determined the exact locations of nest trees. We have developed …


Colonial Waterbird Nesting On West Sister Island National Wildlife Refuge And The Arrival Of Double-Crested Cormorants, Mark C. Shieldcastle, Larry Martin Dec 1997

Colonial Waterbird Nesting On West Sister Island National Wildlife Refuge And The Arrival Of Double-Crested Cormorants, Mark C. Shieldcastle, Larry Martin

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Recent survey data have shown the importance of West Sister Island National Wildlife Refuge, Lake Erie, to nesting waders. About 40 percent of all herons and egrets nesting in the U.S. Great Lakes are found there, including the Great Lakes’ largest colonies of great blue heron (Ardea herodias), great egret (Ardea alba), and black-crowned nightheron (Nycticorax nycticorax), and the largest of two snowy egret (Egretta thula). West Sister Island’s importance to Ohio has grown in recent decades with the loss of smaller mainland colonies of waders, especially the black-crowned night-heron. The double-crested …