BIOLOGY, CONSERVATION AND MANAGEMENT OF THE DOUBLE-CRESTED CORMORANT - SYMPOSIUM SUMMARY AND OVERVIEW

This paper summarizes a symposium on the biology and management of the Double-crested Cormorant (Phalacrocorax auritus) and its interactions with aquaculture. Populations of the Double-crested Cormorant in Nort h America have increased rapidly since 1972, following a period in whi ch they were reduced by toxic effects of DDE. The Double-crested Cormo rant is perceived to be a significant pest of aquaculture, especially the catfish industry in the southern United States. Information on the breeding biology, population dynamics and feeding ecology of the spec ies is incomplete. Although some information on predation of Channel C atfish (Ictalurus punctatus) by cormorants in aquaculture facilities w as presented, there is insufficient information on predator-prey relat ionships or input-output functions to assess fully the ecological or e conomic significance of this predation. Double crested Cormorants are controlled in many areas, but there is little quantitative information on the effects of such control. Management activities have limited sc ientific basis and are driven largely by political considerations. Alt hough more research is needed to improve the scientific basis for mana gement, it is uncertain whether the cost of such a research program wo uld be justified by the potential benefits.