Age and growth of invasive lionfish (Pterois spp.) in the Caribbean Sea, with implications for management

Removal efforts designed to avoid or minimize impacts from introduced lionfish, Pterois volitans (Linnaeus, 1758) and Pterois miles (Bennett, 1828), in the western Atlantic Ocean, Caribbean Sea, and Gulf of Mexico will be improved by reliable life history information applicable to the invaded range. For example, length at age has been modeled for lionfish from temperate North Carolina, but parameters characterizing growth are likely to differ in the tropics. Using Pterois spp. from Little Cayman, we validated formation of annual increments and daily rings in sagittal otoliths; documented ages; and estimated parameters for a length-weight relationship, multiple von Bertalanffy growth models, and an asymptotic vulnerability schedule. Formation of annuli was confirmed with marginal increment analysis, and daily ring deposition in juveniles was confirmed using an oxytetracycline hydrochloride marker. Total weight (g) estimated from combined data for both sexes was equal to 0.000003 x total length (mm)(3.24). Logistic regression indicated that 50% of lionfish were vulnerable to removal at 129 mm total length. Sagittal otoliths (n = 499) from lionfish collected weekly between January and December 2011 indicated that males were 0-5 yrs old and females were 0-3 yrs old. A maximum likelihood approach to fitting von Bertalanffy equations estimated K and L-infinity as 0.42 and 349 mm for the population, 0.38 and 382 mm for males, and 0.57 and 286 mm for females. An age-structured population model indicated that annual exploitation rates of 15%-35% may induce recruitment overfishing, with recovery to 90% of pre-removal biomass occurring 5-20 yrs after removals cease.