HOMING AND ORIENTATION IN THE SPOTTED SPINY LOBSTER, PANULIRUS GUTTATUS (DECAPODA, PALINURIDAE), TOWARDS A SUBTIDAL CORAL REEF HABITAT

Abstract

Panulirus guttatus (Latreille, 1804) is a sedentary, non-migratory species of spiny lobster that lives in the coral reef habitat throughout its benthic life. Homing and orientation of P. guttatus were investigated through experimental displacements of individual lobsters. Lobsters were caught in fixed traps deployed around three coral patches along a reef tract in northern Quintana Roo, Mexico. A total of 145 adult lobsters were tagged and individually released in one of four compass directions corresponding to the following sites as related to their home reef patches: in the reef lagoon (310?, ~W), along the axis of the reef tract (20?, ~N, or 200?, ~S) and in the fore-reef (100?, ~E). In each direction, individuals were displaced over 50, 100, or 200 m away from their point of capture. Thirty lobsters were recaptured, 29 of which in the same area of the reef patch where they had been initially captured, regardless of the time elapsed (1-146 days). The proportion of recaptured lobsters was independent of the direction and distance of release when lobsters were displaced 50 and 100 m into the reef lagoon or along the axis of the reef, but no lobsters were recaptured from a distance of 200 m along the axis of the reef. Hence, the familiar home range of P. guttatus appears to lie within a radius of 100 m along the reef tract, and within this home range individuals possibly use several crevices as refuges. A tethering experiment showed that lobsters significantly moved towards the reef when released on bare sand 500 m away from the reef. Wave surge may have oriented the lobsters towards the reef. These results indicate that, despite their sedentary, non-migratory nature, adult male and female P. guttatus show homing and orientation abilities.