Comparison of Biomechanical Properties of Hermit Crabs
Authors:Carlos De la Parra, Adrianna Hernandez, Amie Nowacki
- Dr. Diana Lieberman, Program Director, Division of Science & Environmental Policy, California State University, Monterey Bay
- Dr. Milton Lieberman, Program Director, San Miguel Biological Station Cabo Blanco Absolute Reserve (MINAET)
Comparison of Biomechanical Properties of Hermit Crabs Authors: Adrianna Hernandez, California State University Los Angeles, Amie Nowacki, Minnesota State University Moorhead, Carlos de la Parra,Cal Poly San Luis Obispo Mentor: Drs. Milton and Diana Lieberman, Natural Science Division, California State University Monterey Bay This study at San Miguel Biological Station, on the Pacific Coast of Costa Rica compared commonly-utilized shell types of hermit crabs. We hypothesized that hermit crabs may prefer a certain shell type that provides the greatest resistance to crushing and allows them to achieve the best performance in terms of crab speed and crab strength. We chose hermit crabs (N=240) from six different species of shells. Half of the individuals were examined for hermit crab performance (pulling force, velocity), and the remaining were utilized for shell physical properties (length, width, thickness of aperture and body). A paired student’s t-test (P˂ 0.05), showed that how well a crab fits within its shell does not affect the performance of the hermit crab. The shell species that offered the best performance were tooth shells. The shell species that proved to have the greatest resistance to crushing were rock shells. The shell species that achieved the highest values for crab speed and strength were average in terms of their resistance to crushing. Based on the results of the tests conducted, the shells that hermit crabs choose most frequently have been found to house crabs that have the best performance. For future research, newly abandoned shells would be ideal to collect in order to compare the strength of fresh shells versus old gastropod shells and perhaps identify if fresh gastropod shells offer higher chances of survival than they would have with the older gastropod shells. Support provided by CSU-LSAMP from NSF HRD-1302873 and Office of the Chancellor.