Meeting Abstract
Intertidal zones represent some of the most thermally dynamic habitats on earth, and are a classic system for understanding the ecological consequences of fine-scale temperature variability. However, most intertidal studies focus on exposed rock surfaces and the organisms that specialize on them, such as mussels and snails. We report fine-scale temperature data for temperatures under rocks on a boulder shore on the coast of Northern California. Data loggers were placed under 24 rocks from the mid- to the high-intertidal zone on a single shore, yielding over 420,000 temperature records across 18 months. Energetic consequences of thermal variability were predicted for the porcelain crab Petrolisthes cinctipes, a common boulder shore native, using laboratory measures of temperature-dependent metabolism in air and water. High intertidal rocks consistently had higher daily maximum and lower daily minimum temperatures than mid intertidal rocks due to longer emersion during warm daytime hours and cold nighttime hours, respectively. Somewhat surprisingly, metabolic expenditure by P. cinctipes was predicted to be very similar between the high and mid zones. This is primarily due to the fact that transient high temperatures experienced during daytime emersion in the high intertidal are offset by cold nighttime temperatures and depression of metabolism in air. Our results demonstrate that the energetic consequences of fine-scale temperature variability in the intertidal can be complicated by unintuitive temperature dynamics and the complex metabolic physiology of intertidal organisms.
