Blue Crab Spawning and Recruitment in Two Gulf Coast and Two Atlantic Estuaries in Florida

Abstract

AbstractThe present study aimed to investigate the life history traits of blue crabs Callinectes sapidus found in four estuarine systems—two on the Gulf coast of Florida (St. Andrews Bay and Suwannee Sound) and two on the Atlantic coast (St. Johns and Halifax rivers). Females in St. Andrews Bay, Suwannee Sound, the St. Johns River, and the Halifax River reached maturity at a carapace width (measured from lateral spine tip to lateral spine tip) of 116.5, 121.9, 129.5, and 123.7 mm, respectively. At both Gulf coast locations, year‐round spawning was not observed; peak spawning occurred in early to late spring, and in St. Andrews Bay there was an additional fall spawning event. On the Atlantic coast, spawning females were collected almost year round, with the greatest abundance in winter through spring and an additional peak in late summer. Potential fecundity on both coasts was directly correlated with body size and was greatest at the beginning of each reproductive season. Egg diameter from crabs on both coasts was independent of female size and was influenced by month, with the largest egg diameters observed in the earlier months of the year. Overall, there was an inverse relationship between potential fecundity and egg diameter. Mean potential fecundity for females sampled in St. Andrews Bay, the Halifax River, and the St. Johns River was 1.8, 2.1, and 2.2 million eggs, respectively. This demonstrates that seasonality is important for blue crab reproductive output and for the timing of juvenile and fishery recruitment.