GILCHRIST, S.L.; NEMCHONOK, E.*; New College of Florida; New College of Florida: Interactions between ants Atta cephalotes, Brachymyrmex sp. and Dorymyrmex sp. and hermit crabs Coenobita clypeatus on lithophytic and scrub plants of Bailey’s Cay, Roatan, Honduras

Ants and hermit crabs commonly co-occur on small cays in the Caribbean. Until recently, little attention has been given to interactions between these arthropods. Land hermit crabs forage on vegetation, shelter in their shade and drink moisture collected on leaves. Ants also use plants for similar activities, suggesting on small, vegetated islands that ants and hermit crabs likely use common resources. Lithophytes and tropical scrub plants located on the cay perimeter and interior were sampled for their ant and crab associates. In addition, potential interactions for resources such as food and water were increased by baiting plants with these items. Tillandsia utriculata and Hymenocallis latifolia and Agave sp were common lithophytic understory plants found on coral rag, occurring in both locations sampled. Borrichia arborescence, Vigna luteola, and Cleome sp were among the common plants found in tropical scrub habitats extending from the beach to the interior of the islands. Ants and hermit crabs were observed feeding directly on plant materials, but agave plants offered the site of greatest interaction. Agave plants were wounded by scraping leaves near the base. Such wounds attracted nearby hermit crabs which widened wounds and ingested liquids from the wounds. Ants living within the plants were recruited to the areas as well, swarming the crabs on average within 15 minutes of arrival. Rarely did more than one ant species occupy a single plant. When placed together on a single plant, workers of both the host and invader attacked each other.