Effects of Simulated Commercial Harvest on Mummichogs in Tidal Creeks in South Carolina, USA

Abstract

The mummichog Fundulus heteroclitus is an economically important species in South Carolina. Mummichogs are harvested commercially to be sold as baitfish and are an important prey item to many economically valuable finfishes. However, little is known about the commercial fishery and how harvesting affects local populations. This study examined the effects of simulating intensive commercial harvest of mummichogs in tidal creeks in South Carolina. Between April 2008 and January 2009, commercial minnow traps were set in five tidal creeks along the lower portion of the Ashepoo River. In three of the creeks, mummichogs were harvested as they would be in a commercial fishery. In the other two creeks, mummichogs were collected but not harvested; these creeks served as controls. In the harvest creeks, 67,487 mummichogs were collected and transported a distance of at least 760 m to finger creeks located across the Ashepoo River, where they were released. In the nonharvest creeks, 73,927 mummichogs were collected and released back at each trap location. The simulated commercial harvest had an effect on the length distribution and abundance of the mummichogs in the test creeks. Results from this study suggest that there would be effects of fishing, but populations would likely not be fished to commercial extinction as long as traps have a mesh size no smaller than that used in this study. We recommend that the regulations for the commercial fishery consist of trap design specifications as well as licensing and landings reporting so that the magnitude of the fishery can be monitored.