Oxygen Uptake during Environmental Temperature Change in Hermit Crabs: Adaptation to Subtidal, Intertidal, and Supratidal Habitats

Changes in oxygen uptake in response to stepwise changes in environmental temperature have been measured in anomuran decapod Crustacea inhabiting a subtidal habitat (Paguristes turgidus, Elassochirus tenuimanus), an intertidal habitat (Pagurus granusimanus, Pagurus hirsutisculus) and a supratidal habitat (Coenobita clypeatus, Coenobita rugosus). Individuals of each species were housed in respirometers and subjected to three rapid, progressive 5 C increases above their initial acclimation temperature, with {aastex} {amsbsy} {amsfonts} {amssymb} {bm} {mathrsfs} {pifont} {stmaryrd} {textcomp} {portland,xspace} {amsmath,amsxtra} {wasysym} {empty} {10}{9}{7}{6} {document}Ṁ_O₂{document} (μM O₂/g/h) measured during a 2-3-h pause at each temperature increment. The Q10 for {aastex} {amsbsy} {amsfonts} {amssymb} {bm} {mathrsfs} {pifont} {stmaryrd} {textcomp} {portland,xspace} {amsmath,amsxtra} {wasysym} {empty} {10}{9}{7}{6} {document}Ṁ_O₂{document} is correlated with habitat, with intertidal species having a Q10 of 1.4-1.6, which is significantly lower (P < .05) when compared with Q10 values of 2.1-2.4 for subtidal species and 2.6-2.7 for the supratidal forms. Intertidal hermit crabs also showed a smaller {aastex} {amsbsy} {amsfonts} {amssymb} {bm} {mathrsfs} {pifont} {stmaryrd} {textcomp} {portland,xspace} {amsmath,amsxtra} {wasysym} {empty} {10}{9}{7}{6} {document}Ṁ_O₂{document} overshoot and a more rapid {aastex} {amsbsy} {amsfonts} {amssymb} {bm} {mathrsfs} {pifont} {stmaryrd} {textcomp} {portland,xspace} {amsmath,amsxtra} {wasysym} {empty} {10}{9}{7}{6} {document}Ṁ_O₂{document} acclimation to abrupt temperature change compared with the other anomurans. Intertidal anomuran Crustacea are apparently adapted to maintain a comparatively stable oxygen uptake in a habitat subject to considerable variability in temperature.