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Changes In The Status, Distribution, And Management Of Double-Crested Cormorants In Wisconsin, Summer W. Matteson, Paul W. Rasmussen, Kenneth L. Stromborg, Thomas I. Meier, Julie Van Stappen, Eric C. Nelson
Changes In The Status, Distribution, And Management Of Double-Crested Cormorants In Wisconsin, Summer W. Matteson, Paul W. Rasmussen, Kenneth L. Stromborg, Thomas I. Meier, Julie Van Stappen, Eric C. Nelson
Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest
We reviewed and summarized historical data and conducted population surveys from 1973 through 1997 to determine the breeding status and distribution of doublecrested cormorants (Phalacrocorax auritus) in Wisconsin. Breeding cormorants historically occupied large, isolated lakes and wetlands in northern Wisconsin, but there were no known nesting sites until 1919, when cormorants were reported nesting on Lake Wisconsin in south-central Wisconsin. From the 1920’s to the 1950’s, cormorants occupied 17 colony sites in 16 counties, though no more than 7 sites were occupied during any particular year. From the 1950’s to the early 1970’s, the number of cormorant nests …
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
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 …