Hermit crabs have an assymetrical and no-sclerotized abdomen which stays sheltered by gastropod shells. The shells protects hermit crabs against predation and dissecation , but influence aspects of their biology, such as fecundity and growth. Due to this influence, hermit crabs periodically seek and exchange their shells when they find a better quality shell (without epibionts , no damaged shells, etc). One way to acquire new shell and exchange the old one is standing in clustering formation with other hermit crabs. Clusters are considered places where hermit crabs find protection against dissecation and predators, where males find females and where "shell exchange markets" are formed. The aim of this project is to study clustering formation, composition and hermit crabs behaviour in this situation at Araçá Bay, north coast of São Paulo state, Brazil. The project will be developed in four stages. The initial part will be identifying the shells and hermit crabs species in clustering formation. Then, experiments will be realized to understand the clustering formation, first with field marking and recapturing animals and, then with clustering formation under controlled tidal in laboratory conditions. Finally, also in laboratory, artificial clusters will be analyzed to verify which are the characteristics of the first hermit crabs that exchange its shell when a new one is add to the system.
News published in Agência FAPESP Newsletter about the scholarship: