| The behavioral thermoregulation of the red swamp crayfish, Procambarus clarkii, was investigated and the environmental parameters of crayfish burrows were measured in situ. Although temperatures within burrows fluctuated less than surface temperatures in the Mojave Desert, crayfish can experience sub-optimal temperatures inside the burrow. In the laboratory, P. clarkii heated and cooled more rapidly in water than in air, selected a water temperature of 22°C, and avoided water temperatures above 31°C and below 12°C. P. clarkii displayed three main shuttling behaviors between water and air and the relative amounts of these behaviors and the time spent in air were significantly greater at 34°C than at 12°C, 16°C, 22°C or 28°C. This reflects an increased use of behavioral thermoregulation at critical temperatures. These periods of emersion were interspersed with frequent dipping in the water, allowing the crayfish to gain the benefits of evaporative cooling, without the physiological costs incurred by long-term exposure to air. |
