RECENT COLONIZATION OF MIDRIFF ISLANDS, GULF OF CALIFORNIA, MEXICO, BY FERAL HONEYBEES, APIS MELLIFERA

Abstract

Honeybees (Apis mellifera) in the Americas are an introduced species that has been established throughout most of the hemisphere for decades or centuries. An exception is the uninhabited Midriff islands in the Gulf of California. Except for the near-shore Isla Tiburón, historical evidence indicates that feral honeybees did not successfully colonize the Midriff islands until about the early 1990s. Today, colonies are well established on the major islands of Tiburón, San Esteban, San Lorenzo, and Ángel de la Guarda, and honeybees forage on 2 smaller islands: Las Ánimas (San Lorenzo Norte) and Mejía. There is no evidence of colonization or foraging on the small and floristically impoverished islands of Salsipuedes, Rasa, Partida Norte, and San Pedro Mártir. Whether the honeybees are Africanized remains undetermined, but is likely in view of the overwater distances to the islands and time of their arrival. Whether Africanized or not, honeybees are an invasive exotic species that could significantly disrupt the largely natural Midriff island ecosystems.