Greetings, The following M.Sc. Thesis (in Spanish) as been recently accepted as a partial fulfillment to obtain the degree of Master in Science with speciality in Marine Resources Management. PDF reprints are available upon request to the author (biomario@gmail.com or mpardor0600@ipn.mx): Pardo, M.A. (2009) Physicochemical and biological conditions modulating cetacean abundance on Alfonso Basin, Gulf of California. M.Sc. Thesis. Instituto Politecnico Nacional - Centro Interdisciplinario de Ciencias Marinas. La Paz, BCS, Mexico. 122p. Regards, -- Mario A. Pardo Instituto Politécnico Nacional Centro Interdisciplinario de Ciencias Marinas Departamento de Oceanologia Laboratorio de Ecología de Cetáceos y Quelonios La Paz, B.C.S. México Voz: (+521) 612 1404111 Correo: biomario@gmail.com mpardor0600@ipn.mx URL: www.cicimar.ipn.mx