Allozyme data, combined with traditional morphological and anatomical data, were used to evaluate the genetic status of the island endemic, Cercocarpus traskiae (Catalina mahogany). Comprising only seven adult plants and close to 70 seedlings, C. traskiae is confined to Wild Boar Gully on the southwest side of Santa Catalina Island in Los Angeles County, California Electrophoretic examination of 22 enzyme loci revealed that all but two of the seven adult C. traskiae trees were unique allozymically. Furthermore four of the seven C. traskiae individuals were morphologically and/or anatomically intermediate between “true”C. traskiae and the more abundant Cercocarpus species on Santa Catalina, C. betuloides var, blancheae. Further electrophoretic analyses revealed that two of these four individuals possessed an additive “hybrid” enzyme phenotype indicating that these individuals were hybrid. Twenty-five of the seedlings were also assayed but none of the seedlings displayed hybrid enzyme phenotypes. Given the evidence for hybridization described herein, we make two suggestions to enhance the long-term preservation of C. traskiae. First, it may be desirable to eliminate the single C. betuloides var.: blancheae individual in Wild Boar Gully. Second, we suggest that established cuttings of true C. traskiae be transplanted to areas on Santa Catalina where the probability of hybridization is minimal Our data further demonstrate that accurate taxonomic identification and an understanding of population genetic structure are necessary for the enlightened management of small relict populations or island endemics. Resumen: Datos de alloenzimas combinados con datos tradicionales morfologicos y anatomicos, fueron usados para evaluar el estado genetico de la especie endmica, Cercocarpus traskiae (Catalina Mahogany). Incluiendo solo siete plantas adultas y cerca de 70 plantones, C. traskiae esta limitado al Wild Boar Gulley en el lado sureste de la Isla Santa Catalina en Los Angeles, California. En examen electroforetico de 22 loci de enzima, revelo que todos, menos 2 de los siete arboles adultos C. traskiae, fueron alloenzimaticamente unicos. Ademas cuatro de los siete individuos C. traskiae fueron morfologicamente y/o anutomicamente intermedios entre el “verdadero”C. traskiae y las mas abundante especie de Cercocarpus en Santa Catalina. C. betuloides var. blancheae. Mayor analisis electroforotico revelo que dos de estos cuatro individuos poseian un fenotipo enzimatico hibrido aditivo, indicando que estos individuos eran hibridos. Vienticinco de los plantones plantones tambien fueron analizados, pero niguno de los plantones mostraron fenotipos enzimaticos bibridos. Dada la evidencia de hibridacion descrita aqui bacemos dos sugerencias para aumentar la preservacion al largo plazo de C. traskiae Primero, puede ser deseable eliminar el unico C. betuloides var. blancheae en “Wild Boar Gully.” Segundo, sugerimos que esquejes establecidos de C. traskiae verdaderos Sean trasplantadas a areas en Santa Catalina donde la probabilidad de hibridacion es minima Neustros datos demuestran adicionalmente que la identifcacion taxonomica precisa y un entendimiento de la estructura genetica poblacional son necesarios para el manejo racional de las poblaciones pequenas relictas o enedmicas de islas.