Meeting Abstract
The intertidal zone porcelain crab, Petrolisthes cinctipes, is likely to respond to increased abiotic stress (maximal habitat temperature) by moving lower in the tidal zone resulting in aggressive interactions with subtidal congeners. We aim to determine experimentally whether increased temperature causes P. cinctipes to move and to investigate the indirect effects on behavioral interactions. We hypothesize that crabs experiencing higher temperatures will see significantly higher injuries than crabs under less thermal stress. Tides and temperatures (8°C to 37°C) were taken from iButton data logger recordings at all tidal heights at the collection site in Fort Ross, California. Temperatures were used as-is for some treatments, and manipulated to reflect future climatic scenarios for other treatments. Reflecting field data, the female to male ratio is 4:6 and size ranges between 7-14mm distributed equally between treatments. Laboratory enclosures were built with high and low intertidal zones joined by a ramp allowing P. cinctipes crabs to move between zones. Injuries such as leg loss or exoskeleton scarring and mortality were monitored as an indicator for the indirect effects of temperature on behavior. Leg loss was observed most often. Observations showed P. cinctipes staying in the cool zone for treatments with higher temperatures and in both zones for low temperature treatments. Distribution changes and novel interactions have the potential to cause ecosystem-wide effects. A broader understanding of the combined effects of abiotic and behavioral stress will inform indirect behavioral responses of ectotherms to climate warming.
