Assessing the potential for natural predators to control the spread of the Suminoe oyster, Crassostrea ariakensis
Eastern oyster
(Crassostrea virginica) stocks in Chesapeake Bay are essentially non-existent due to the long-term adverse effects of over harvesting and the ongoing epizootics of two protistan diseases, MSX and Dermo. This loss of suspension feeding oysters has reduced their crucial ecosystem role and imposed severe economic hardships associated with the collapse of the once valuable oyster fishery. Currently there is discussion about introducing the non-native Suminoe oyster,
C. ariakensis, as a replacement species because of its tolerance to disease and fast growth to market size. There is a legitimate concern, however, that such an introduction may lead to the establishment of feral oyster populations that have the potential to become a nuisance species not only in Chesapeake Bay but in other locations along the Atlantic coast of North America. We will investigate if
C. ariakensis spat are as vulnerable as
C. virginica spat to predators in the first weeks to months after larval settlement and metamorphosis. This is a critical period for survival of many marine organisms and if we find that this non-native oyster can escape predator control it indicates that it may become highly abundant, perhaps to the point of becoming a nuisance species. Alternatively, if we find that the same suite of natural predators that control the abundance of
C. virginica also feed with high intensity on
C. ariakensis spat, it will indicate that there is a natural biological control mechanism that will serve to curb extreme population growth.
|
Roger I.E. Newll and Victor S. Kennedy
Horn Point Laboratory
University of Maryland Center for Environmental Science
|
|
|
