Impacts of red snapper mortality associated with the explosive removal of oil and gas structures on stock assessments of red snapper in the Gulf of Mexico

Abstract

An average of 96 oil and gas structures are removed with explosives annually from the U.S. Gulf of Mexico. These offshore structures function as artificial reefs attracting a wide variety of marine life, including the commercial and recreationally important red snapper. A multi-year study estimated the mortality of red snapper resulting from the explosive removal of nine platforms at water depths of 14–36 m. Estimated mortality of red snapper due to underwater explosives averaged 515 per platform. Using this value, we estimated the total annual mortality of red snapper resulting from all explosive structure removals in the U.S. Gulf of Mexico. The recent stock assessment for red snapper (Schirripa and Legault 1999) was subsequently recalculated, including this additional source of mortality. Results showed no discernible difference between the two stock assessments, indicating that direct mortality resulting from explosive structure removals was minor compared with other sources of mortality.