Effects of temperature on activity, food consumption rates, and gut passage times of three seaweed-eating species of Tegula (Trochidae) from central and southern California

Herbivorous ectothermic snails may experience difficulty obtaining sufficient nutrients, limiting their ability to sustain populations under sub-optimal sea temperatures. I hypothesized that, at different temperatures, activity, consumption rates, and gut passage times of three Tegula species would correspond with temperatures characteristic of their geographic distributions: T. brunnea (cold water), T. aureotincta (warm water), and T. funebralis from warm and cold waters. Activity and consumption rates of T. aureotincta increased with temperature; of T. brunnea's were highest at 19°C and lowest at 11°C; warm-water T. funebralis' were lowest at 11°C; and food consumption of cold-water T. funebralis was fastest at 15°C but activity was highest at 23°C. Temperature affected gut passage time of only T. aureotincta. Temperature's effect on activity and consumption rates might influence the northern limit of T. aureotincta. T. brunnea's activity and consumption rates were not hindered by warmer temperatures. Widely separated T. funebralis populations may be adapted to regional conditions.