Disciplines
Aquaculture and Fisheries | Biodiversity | Evolution | Marine Biology
Abstract (300 words maximum)
Lionfish are invasive in the Atlantic and the Caribbean. Like many other invasive species, they do not have any natural predators in these areas, so their population can grow unchecked. This can decrease the population of native fish species due to lionfish eating to excess. Because of their impact on native species, resource managers have incentivized lionfish hunting. Hunters were paid $6 USD for every pound of lionfish they brought in, so they possibly favored larger lionfish to increase their reward which would lead to an adaptive advantage for fish of smaller sizes. We hypothesized that the lionfish bounty program would affect the average size of lionfish and the size of females at sexual maturity, both of which should decrease. Since 2019, local fisherman brought their lionfish catch to the Tobacco Caye Marine Station to retrieve a financial bounty. Data on fish size, sex, and reproductive status was then obtained from the fish. These data were used to determine the percentage of female lionfish in each of three categories: those that were not sexually mature, those that were, and those that were in the intermediate phase of development. This data was used in conjunction with fish size to estimate the size at sexual maturity. Over the study, the size distribution of mature females appeared to decline. In 2019-2020, the smallest mature lionfish was 18-20 cm, and the average length of mature females was over 20 cm in size. By 2022, the average size of mature fish was 18.5 cm with higher percentages of mature fish in the smaller size classes than in previous years. Differential sampling effort was not accounted for in this study and would need to be addressed before drawing robust conclusions. However, the pattern suggests fishing pressure could drive earlier sexual maturation.
Academic department under which the project should be listed
CSM - Ecology, Evolution, and Organismal Biology
Primary Investigator (PI) Name
Troy Mutchler
Additional Faculty
Not applicable.
Included in
Aquaculture and Fisheries Commons, Biodiversity Commons, Evolution Commons, Marine Biology Commons
Culled Lionfish Sexual Maturity Over A Four-Year Timespan
Lionfish are invasive in the Atlantic and the Caribbean. Like many other invasive species, they do not have any natural predators in these areas, so their population can grow unchecked. This can decrease the population of native fish species due to lionfish eating to excess. Because of their impact on native species, resource managers have incentivized lionfish hunting. Hunters were paid $6 USD for every pound of lionfish they brought in, so they possibly favored larger lionfish to increase their reward which would lead to an adaptive advantage for fish of smaller sizes. We hypothesized that the lionfish bounty program would affect the average size of lionfish and the size of females at sexual maturity, both of which should decrease. Since 2019, local fisherman brought their lionfish catch to the Tobacco Caye Marine Station to retrieve a financial bounty. Data on fish size, sex, and reproductive status was then obtained from the fish. These data were used to determine the percentage of female lionfish in each of three categories: those that were not sexually mature, those that were, and those that were in the intermediate phase of development. This data was used in conjunction with fish size to estimate the size at sexual maturity. Over the study, the size distribution of mature females appeared to decline. In 2019-2020, the smallest mature lionfish was 18-20 cm, and the average length of mature females was over 20 cm in size. By 2022, the average size of mature fish was 18.5 cm with higher percentages of mature fish in the smaller size classes than in previous years. Differential sampling effort was not accounted for in this study and would need to be addressed before drawing robust conclusions. However, the pattern suggests fishing pressure could drive earlier sexual maturation.