Impacts of mycobacteriosis on the growth of striped bass (Morone saxatilis) in Chesapeake Bay.

摘要

The striped bass (Morone saxatilis) is an economically and ecologically valuable finfish species that inhabits nearshore and estuarine waters of many states along the US Atlantic coast. Chesapeake Bay provides extensive nursery and foraging habitats for striped bass, yet fish in the bay exhibit high prevalence of disease caused by bacteria in the genus Mycobacterium. Detection of population-level impacts associated with mycobacteriosis has been difficult because the disease is chronic and synoptic biological and disease data have been limited. Here, we present modeling analyses of growth data for disease-positive and -negative striped bass in Chesapeake Bay. Three growth relationships were considered, and for each, a single model was parameterized to include several covariates, most notably disease status and severity. Our results indicate that disease-positive and -negative fish have differing growth patterns and that the estimated asymptotic sizes of disease-positive fish are considerably lower than those of disease-negative fish. Compromised growth along with documentation that striped bass in Chesapeake Bay are experiencing disease-associated mortality suggests that disease may be reducing the productivity of this species.Digital Object Identifier http://dx.doi.org/10.1139/f2011-158