(full paper is archived in the Miller Library)
Title: Distribution and utilization of gastropod shells by the hermit crabs Pagurus samuelis, Pagurus granosimanus, and Pagurus hirsutiusculus at Pacific Grove, California
Student Author(s): Bollay, Melody
Location: Final Papers Biology 175H
Date: June 1963
Keywords: black turban snail
Abstract: 1) Of the three species of hermit crabs found in the intertidal zone at Hopkins Marine Station, Pacific Grove, Pagurus samuelis is the only one encountered at positions higher than about 1.2 m, P. hirsutiusculus and P. granosimanus being found lower. 2) Of the three species, Pagurus samuelis appears to be able to survive exposure out of water better than the other two. Adults of P. hirsutiusculus are least able to withstand exposure to air in sunlight. 3) The three species make use of various shells to different degrees. 89% of the Pagurus granosimanus and 75.9% of the P. samuelis collected occupy Tegula funebralis shells, whereas, the smaller P. hirsutiusculus tended to occupy shells of smaller snails such as Epitonium, Mitrella, Homolapoma, etc. to a greater degree. 4) The bigger Pagurid individuals are largely dependent on Tegula funebralis for homes whereas the smaller sized hermit crabs are not, and occupy a variety of small shells. 5) Both Pagurus samuelis and P. hirusutiusculus attain sexual maturity at a relatively small size and thus are not completely dependent on Tegula funebralis for the survival and reproduction of the species. However, when larger shells are not available, the reproduction potential in P. samuelis may be greatly reduced since the smaller individuals produce far fewer eggs than the larger ones.
Notes: Published 1964, Veliger 6(suppl.):71-76