Respiration rates for the intertidal spider desis marina (Hector)

Abstract

Respiration experiments involving the intertidal spider Desis marina (Hector) yielded a respiration (μl h-1) - weight (mg) relationship of log10R = 0.61 log10W - 0.61 at 17.5°C; which is much lower (< 50%) than the rates obtained for terrestrial spiders. D. marina was also able to survive until oxygen partial pressures fell to 18-24 mmHg (12% of ambient levels). These 2 features help explain how D. marina are able to withstand long periods of submergence in bull kelp holdfasts on the shore. Calculations and experiments involving air spaces which did not contain spiders both suggested that the ‘physical gill effect’ should provide enough oxygen to ensure > 100 days underwater survival for even the largest animals. However, survival and respiration experiments suggested that the spiders ‘conditioned’ their environment so that the physical gill effect was reduced to providing only 3-10% (depending upon weight) of the required oxygen. © 1983 Taylor & Francis Group, LLC.