Do red snapper migrate around the Gulf of Mexico?
The red snapper in the GOM is currently managed under the “unit stock hypothesis;” this generally implies that there is both a great deal of long-distance movement by individuals and little genetic difference among individuals and populations throughout the GOM. Management of red snapper under the unit stock hypothesis also has the advantage of simplicity in both the application and enforcement of regulations. Tagging studies (in which fish are caught, tagged, released and hopefully re-caught at a later time) have shown that red snapper are indeed capable of movements as much as 350 miles, especially when motivated to do so by tropical storms and hurricanes. However, in these same studies, the vast majority of tagged red snappers are recaptured within a few miles of their initial tagging sites, even after several years of post-tagging freedom. Genetic studies analyzing both nuclear DNA and mitochondrial DNA have generally been unable to refute the unit stock theory; however, they have
