Behavioural responses of some rocky shore fish exposed to adverse environmental conditions

The behavioural responses of three littoral teleosts, Lipophrys (=Blennus) pholis, Taurulus (= Cottus) bubalis and Ciliata mustella to changing environmental pO2, salinity, temperature, pH and pCO2 were investigated. Both L. pholis and T. bubalis emerge from seawater and climb onto land at low oxygen tensions but only L. pholis is very mobile once out of water; the values inducing emergence are significantly lower in T. bubalis than in L. pholis and it is likely that the latter species is often stimulated to emerge from natural rock pools at night. In both species the emergence response occurs at much higher oxygen tensions at higher temperatures. C. mustella tried to escape from oxygen deficient water but its morphology made climbing impossible. None of the three species showed emergence responses to falling salinity, changing pH levels, rising temperature or increased pCO2.