Post-release Survival and Barotrauma

The continental shelf waters off the southeastern United States are home to over 100 species of demersal (seafloor-associated) fish. When caught, these fish sometimes experience injuries called barotrauma as a result of the pressure change from seafloor to the surface (see gallery). Barotrauma can vary in its severity, but sometimes results in expanded swim bladder gases that cause the fish to float. Unable to re-submerge, floating fish are destined to die without intervention.

Enter descender devices. These handy tools push or pull floating fish back down to a depth where gases recompress. Descender (or descending) devices can be as simple as an inverted milk crate or as complex as the SeaQualizer tool (which has an incorporated pressure sensor allowing a pre-specified release depth). One focus of my research has been evaluating the effectiveness of descender devices in increasing post-release (or discard) survival for a variety of species. We have used conventional and electronic tagging to evaluate survival. Overall, we have shown that descender devices are very effective for increasing survival in several species of groupers, black sea bass, and red snapper.

See a descender device in action below!

Visit my Publications section for papers on descender devices.

Marine Protected Areas

In 2009, the United States designated eight Marine Protected Areas (MPAs) off the southeastern United States. The stated purpose of these MPAs was to protected and rebuild populations of deep-water demersal fishes such as groupers. In the decade (+) since closure, few studies have examined the effectiveness of these areas. Part of my research focuses on using a multifaceted approach to evaluate the largest MPA in this network, called the Snowy Wreck Marine Protected Area. We are using scientific sonar and biological data collected in 2007-2009 and 2018-2020 to compare fish populations inside and outside this MPA. Analyses are in progress; please contact me for more information.