Ecology and Life History of Snook Species in Texas

Abstract

AbstractIn recent years, the abundance and distribution of snook species (Centropomus spp.) have increased and expanded in Texas. As mobile predators, snook have the potential to alter marine communities as they expand; however, little is known about the functional impact of snook in Texas. Here, a long‐term (1982–2019) fishery‐independent data set was utilized to describe snook life history characteristics. Bag‐seine and gill‐net data were used to determine distribution, size, spawning, and recruitment seasonality for Common Snook C. undecimalis and Fat Snook C. parallelus in Texas. Snook collected from the lower Laguna Madre were used to describe diet, length–weight relationships, and sex ratios. Results indicated that both Common and Fat snook abundance and range increased in Texas with expansion primarily led by Common Snook. Common Snook were larger than Fat Snook based on the length frequency analysis, but the latter were heavier at a given length. Spawning season for both species occurred during summer and peaked in July and August for Fat and Common snook, respectively. Evidence for protandric hermaphroditism was observed in Common Snook with females being significantly larger than males and a 50:50 male‐to‐female ratio occurring at 670 mm total length (TL). Diet analyses indicated that Common and Fat snook are generalist predators feeding on a variety of prey species. An ontogenetic shift in diet was observed in Common Snook as individuals <500 mm TL fed primarily on shrimp, and those ≥500 mm TL fed primarily on fish. Fat Snook and subadult Common Snook possessed a high degree of dietary overlap, with shrimp being the most common prey item identified for each. These findings provide managers with the foundational aspects of snook life history at a time when the potential effects of the snook range expansion in Texas remain largely undescribed.