Research and development studies involving red drum and hybrid striped bass culture in coastal ponds have been seriously impacted by avian predators, especially when overwintering was required. Studies were conducted at the Waddell Mariculture Center to document the effect of predation by birds and also to test various non-lethal control techniques. Use of pyrotechnics, flash tape, "evil-eye" balloons, aerial balloons, and various wire grid patterns over a pond offered only short term protection. Mortality of fish in ponds protected by these devices ranged from 42.0% to 99.7% depending primarily on duration of the studies. Phase II red drum reared in unprotected "control" ponds exhibited mortalities of 79.5% to 83.1% after 1 month and 99.8% after 8 months. Double-crested cormorants were by far the most destructive predator and they quickly learned how to ignore or avoid the various discouragement devices tested. Total pond covers with plastic meshes did control bird predation but were expensive.
