The Limpet Pivot: Microhabitat Use by Intertidal Limpets on Natural and Artificial Substrates at Friday Harbor Laboratories

Abstract

Habitat structure strongly influences the distribution and behavior of intertidal gastropods. To examine how microhabitat availability shapes limpet behavior, I conducted a comparative field survey of limpets (Lottia spp.) on a natural rocky beach and an adjacent artificial dock environment at Friday Harbor Laboratories (FHL), Washington, USA. Limpets were quantified across microhabitat categories including refuge, exposed, and submerged positions. Limpets were more abundant on the beach (n = 24) than on the dock (n = 10). Beach limpets were disproportionately exposed (67%), whereas dock limpets exhibited a more even distribution across exposed and refuge positions. These results suggest that natural rocky substrates provide more diverse microhabitats, enabling limpets to occupy shaded and moisture-retaining refuges, while artificial structures constrain microhabitat choice. The findings highlight how anthropogenic substrates alter small-scale habitat availability and may influence limpet distribution and behavior.