Abstract

The rate and direction of Panulirus argus emigration and distance lobsters moved when selecting dens were measured at three sites in the Florida Keys to evaluate the potential differences of subadult and adult life-stages on movement. The first site, Coral Gardens was in the Atlantic nearshore waters of the Florida Keys with predominately small subadult lobsters. The second site, Snipe Point was in Gulf of Mexico; a site with subadults that were typically larger than the adult lobsters at the third site, Western Sambo. Western Sambo was in the Atlantic, but further from shore than Coral Gardens. At each site, we deployed acoustic receivers with overlapping detection areas to estimate locations of the 14 to 39 lobsters tagged per site. We found the probability of lobsters’ changing their den (daytime shelter location) and the distance moved were virtually identical at Snipe Point and Western Sambo but distance moved was less at Coral Gardens. Emigrations were detected in all three sites and were estimated between one and two percent per day. Emigration directions were different, westward for Snipe Point, southward for Coral Gardens and omnidirectional for Western Sambo. Emigration patterns at Snipe Point and Coral Gardens were consistent with other studies showing radial migration of juvenile lobsters emanating from Florida Bay that, in this study become highly directional towards adult habitat as the lobsters grew and become subadults. These other studies found faster growth in northern Florida Bay which may explain the large size of subadults we found at Snipe Point.

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