Determination of preferred habitats of early benthic juvenile California spiny lobster, Panulirus interruptus, on the Pacific coast of Baja California Sur, Mexico

Abstract

The habitat requirements of early benthic stage juveniles of California spiny lobster Panulirus interruptus are known only from studies conducted near its northernmost geographic range, where environmental conditions differ markedly from those along the Pacific coast of the southern Baja California Peninsula (Mexico). We determined the natural habitat of this stage of P. interruptus in the central portion of their range from sampling the available dominant vegetated habitats included various seagrasses and macroalgae. Additionally, experiments on habitat selection by early benthic juvenile P. interruptus were performed under laboratory conditions to test natural substrate selection and whether selection of substrata is affected by odour signals. Despite the abundance of different macrophytes as habitat, 93% of the juvenile lobsters were found at the base of the blades of Phyllospadix spp. in the intertidal zone at 0 to 3 m. The highest juvenile densities were found in September at both sites. In laboratory experiments, juvenile lobsters preferred, in order of preference, Gelidium robustum, Phyllospadix, Plocamium pacificum, and holdfasts of the kelp Macrocystis pyrifera. A second laboratory experiment showed that these preferences were affected by odour signals. Results indicate that the ecology of juvenile P. interruptus off the coast of the Mexican Baja is similar to that observed off the coast of southern California.