Metabolic consequences of shell choice in Pagurus bernhardus: do hermit crabs prefer cryptic or portable shells?
- 416 Downloads
Hermit crabs are unique among crustaceans in that they choose their shell and can, therefore, be used to investigate apparent preferences for the presence of epizoic fauna. These may be beneficial due to increased protection from predators via enhanced crypsis but may also make the shell more difficult to carry. The effects of encrusting fauna on the physical properties of empty gastropod shells, the shell preferences of hermit crabs and the physiological costs of shell carrying were examined in the present laboratory study. Heavily encrusted shells weighed more than shells of the same internal volume that were free of epizoic fauna, hermit crabs showed a clear preference for un-encrusted shells and those that occupied encrusted shells had elevated haemolymph lactate in comparison to those supplied with un-encrusted shells. Under laboratory conditions, any benefit from increased crypsis is, therefore, outbalanced by the increased costs of carrying encrusted shells.
KeywordsHermit Crab Internal Volume Lactic Acid Concentration Shell Type Food Odour
We are grateful to three anonymous referees for their comments on the manuscript and to Jon Russ for his comments on an earlier version of the manuscript. This work was funded by the UK BBSRC
- Elwood RW, Neil SJ (1992) Assessments and decisions: a study of information gathering by hermit crabs. Chapman & Hall, LondonGoogle Scholar
- Gutmann I, Wahlefeld AW (1974) l-(+)-Lactate determination with lactate dehydrogenase and NAD+. In: Bergemeyer HU (ed) Methods of enzymatic analysis, 2nd edn. Academic Press, New York, pp 1464–1468Google Scholar
- Hazlett BA, Rittschof D, Bach CE (in press) The effects of shell size and coil orientation in female hermit crabs, Clibanarius vittatus. J Exp Mar Biol EcolGoogle Scholar
- Herreid CF, Full RJ (1986) Energetics of hermit crabs during locomotion: the cost of carrying a shell. J Exp Biol 120:297–308Google Scholar
- Markham JC (1968) Notes on growth-patterns and shell-utilization of the hermit crab Pagurus bernhardus (L.). Ophelia 5:189–205Google Scholar
- Osorno JL, Contreras-Garduno J, Marcias-Garcia C (in press) Long-term costs of using heavy shells in a terrestrial hermit crabs and limits of shell preference: an experimental study. J ZoolGoogle Scholar
- Partridge BL (1980) Background camouflage: an additional parameter in hermit crab shell selection and subsequent behaviour. Bull Mar Sci 30:914–916Google Scholar
- Turra A (2003) Shell condition and adequacy of three sympatric intertidal hermit crab populations. J Nat Hist 47:1781–1795Google Scholar