On the Current Cover of the Journal of Great Lakes Research

Volume 36, 2

Cormorants and Shags are members of the Phalacrocoracidae family with 39 species world wide; they are related to other Pelecaniformes including gannets, boobies, and pelicans. Cormorants are piscivorous water birds well evolved for their feeding strategy with some species routinely diving to depths of more than 20 meters to capture their prey. While some species have been used by Asian cultures for harvesting fish for hundreds of years, in more recent times, the double-crested cormorant (Phalacrocorax auritus) and great cormorant (Phalacrocorax carbo) have become controversial in fish management issues in North America and Europe respectively. Double-crested cormorant populations have been growing in the past few decades with the reduction of DDT in the environment which resulted in increased reproduction rates. Furthermore, the establishment of small-bodied exotic fish species in the Great Lakes, where cormorants nest, and the growth of the aquaculture industry in the Gulf Coast Region of the United States, where they overwinter, contributed to improved fecundity and over-winter survival. This consequence of this population growth on the sports and commercial fisheries is a subject of intense debate with researchers and managers investigating different aspects of these issues. Featured in this issue of the Journal of Great Lakes Research are a series of cormorant papers which discuss different aspects of their ecology and management. This photograph of a double-crested cormorant was collected as part of a tagging operation conducted by the Michigan office of Wildlife Services (USDA; APHIS) in the Les Cheneaux Islands region of Lake Huron in May of 2004.

Photo by David Kenyon, Michigan Department of Natural Resources and Environment.

Volume 36, Supplement 1

Lake whitefish Coregonus clupeaformis is an economically, ecologically, and culturally important species throughout the Laurentian Great Lakes. Recent reductions in fish growth rates and body condition have raised concerns among fishery managers and biologists as to the overall health and future sustainability of lake whitefish populations in the Great Lakes. Among the concerns raised are whether reductions in growth rates and body condition have increased pathogenic infection rates, such as the swimbladder nematode Cystidicola farionis (illustrated in lower right corner), lowered rates of recruitment at either early (illustrated in lower left corner) or later life stages (illustrated in lower left center), or elevated natural mortality rates. This special issue was conceived as a way to disseminate results from several research projects intended to improve understanding of how lake whitefish populations are being affected by reductions in growth rates and body condition. The papers included in this special issue address a variety of areas concerning lake whitefish health and stock status, including pathogens, movement and stock intermixing, feeding, recruitment potential, and natural mortality. Managers and researchers both within and outside the Great Lakes basin will find this special issue a useful resource as it contains a wealth of information, which should prove beneficial for managing lake whitefish populations.

Photograph credits: P. Vecsei, Golder Associates Ltd. (top), A. Muir, Golder Associates Ltd. (lower left corner, lower left center, lower right center), M. Faisal, Michigan State University (lower right corner).