Life History of the Non-Native Invasive Red Lionfish (\u3ci\u3ePterois volitans\u3c/i\u3e) in the Northern Gulf of Mexico

Invasive Red Lionfish (Pterois volitans) were first detected in the northern Gulf of Mexico (nGOM) in 2010 and since then their numbers have increased dramatically. From 2010 to 2015, more than 15,000 Red Lionfish were collected opportunistically from the nGOM for this study. Length and weight relationships differed significantly among ecoregions by sex and there was clear sexual dimorphism in size with males being larger and heavier. Red Lionfish age ranged from 0-4.5 years old and males achieved greater growth rate (K) and asymptotic maximum lengths (Linf) compared to females and these parameters were also different by ecoregion. Total length at 50% maturity was greater for females compared to males. Histological examination of female gonads resulted in the confirmation of asynchronous oocyte development. Additionally, the accuracy of reproductive phases identified macroscopically were significantly different than the corresponding phase identified microscopically. Gonadosomatic index values were elevated for both males and females from May-October, coinciding with elevated water temperatures. On average, a female Red Lionfish in the nGOM is capable of spawning every 2.49 days, 11 months out of the year. Mean batch fecundity was 26,904 eggs and mean relative batch fecundity was 92.2 eggs/g of gonad free body weight and peaked during the warmer months. From this information, an average size mature female of 188.6g is capable of producing 2,332,490 eggs/year. This study provides the most comprehensive description of invasive Red Lionfish reproduction, age and growth, to date, in the nGOM and will be used in creating management plans