Growth parameters of the invasive lionfish (Pterois volitans) in the Colombian Caribbean

Abstract

The success of the lionfish invasion in the western Atlantic can be explained by its rapid dispersion rate, as well as a rapid population growth due to its high fecundity. The adequate invasion control measures may vary between (sub) populations of the wider Caribbean region with differences in ecological and environmental conditions. Lionfish growth studies have been conducted in several places in the invaded region, but are missing from the southern Caribbean. We estimated the growth parameters and empirical natural mortality rates of P. volitans in the Colombian Caribbean and compare them with other native mesopredatory fish. To do so, we used Tropfish R and fishboot, a recently developed statistical stock assessment package that incorporates resampling techniques and allows for estimating the confidence interval around the estimates. Size records of 1184 speared fish caught between 2014 and 2017 in continental and insular reef areas were analyzed. Our results confirm the rapid growth of lionfish (K=0.44; C=0.62) and reveal high similarities in growth rate among Colombian Caribbean areas but differences among the invaded area regions, primarily explained by water temperature, habitat heterogeneity and structural complexity, food availability, potential bathymetric ontogenetic movement, and the time elapsed since colonization. The invader’s efficiency over its competitors is best explained by the lionfish’s fast growth and early age at maturity.