EFFECT OF BENTHIC MICROHABITAT CUES ON THE METAMORPHOSIS OF PUERULI OF THE SPINY LOBSTER PANULIRUS-ARGUS

To determine whether settlement microhabitat induces metamorphosis in the puerulus stage of the Caribbean spiny lobster (Panulirus argus) and to identify the specific features of the habitat that might elicit the response, we monitored the metamorphic progress of more than 200 pueruli exposed to 6 different settlement substrates: sea water alone (no substrate), red algae, sea grass, artificial algae, algae-treated sea water, and artificial algae plus algae-treated sea water. Initial pigmentation followed settlement by approximately 1 day and began 3-6 days (mean = 5 days) after the swimming pueruli were intercepted entering the Florida Bay nursery. Presence of red algae, Laurencia spp., a preferred settlement substrate, accelerated the rate of pigmentation, but by < 1 day. Metamorphosis to the first benthic juvenile stage occurred 7-9 days (mean = 8 days) after pueruli entered the bay and was unaffected by any of the substrates tested. Rates of both pigmentation and metamorphosis varied by as much as 2 days among replicate experiments conducted during the summers of 1986-1988. These results suggest that metamorphosis of pueruli of P. argus is essentially determinant; thus, physiological constraints may limit the distance that pueruli can disperse into the nursery and may force many pueruli to settle in inappropriate habitats where survival is improbable.