Den sharing by juvenile Caribbean spiny lobsters (Panulirus argus) in nursery habitat: cooperation or coincidence?

• DOI: 10.1071/mf97158
• Publication Date: 2004-02-10T02:53:27Z
• Authors: Michael J. Childress; William F. Herrnkind
• Keywords: Panulirus argus; Cannibalism

Spiny lobsters (Palinuridae) commonly share crevice shelters with conspecifics, a behaviour usually hypothesized to benefit mutually cooperative defenders through reduced predation risk. The group-defence hypothesis predicts suite of distinct corollary life history traits and ecological correlates including more frequent co-denning than solitary denning, especially where predators or den competitors are numerous when the small, moulting otherwise vulnerable. Two alternative hypotheses, dilution effect (a type selfish herding) guide (attraction denned conspecific), have different distinctive sets predictions. To test among these den-sharing patterns newly emerged postalgal juveniles Panulirus argus associated conditions in Florida Bay (USA) nursery habitat were examined. Only half shared dens, rarely was sharing an area greater that expected by chance. Den-sharing frequency most highly correlated conspecific density scarcity local dens. lack correlation between lobster size, moult condition, shelter predator failed support either dilution-effect hypothesis. Instead, data better guide-effect