Zoo Biology 14:395-402 (1 995) RESEARCH ARTICLES Assessment of Conservation Units for

An assessment of conservation units for the Sumatran rhinoceros (Dicerorhinus sronarretrsis) was conducted using a population aggregation analysis (PAA) of mitochondrial DNA site substitutions. Populations were defined ss the three geo-graphically separated regions of West Malaysia, Sumatra, and Borneo. The intent of this assessment was to explore management options for this highly endangered lineage rather than conduct a traditional taxonomic revision. Individual DNA positions were not diagnostic for any population. A single haplotype provided a character as support for diagnosing the West Malaysian and Bornean population. The haplotypes on West Malaysia and Sumatra were more similar to each other than either was to the one on Borneo. These data, and a review of the morphological characters, support the option of treating Sumatran rhinos as a single conservation unit, providing managers with greater flexibility in managing the unique Dicerortline lineage. 0 1995 ~ i l e y- ~ i s s. Inc. Key words: subspecies, population aggregation analysis, mitochondrial DNA, conserva-tion uni