Oryzomys - Human Interactions

Human Interactions

Two species of Oryzomys, O. antillarum and O. nelsoni, have gone extinct since the 19th century, and a third, O. peninsulae, is unlikely to be still extant. Their extinction may have been caused by habitat destruction and by introduced species such as the small Asian mongoose and the brown and black rat. These same causes may threaten O. gorgasi, which the IUCN Red List assesses as "Endangered". O. albiventer has been affected by human alteration of its habitat, but likely still survives. In contrast, the widespread species, the marsh rice rat and O. couesi, are common and of no conservation concern—indeed, both have been considered a pest—but some populations are threatened. Like these two species, O. dimidiatus is assessed as "Least Concern" by the Red List.

The marsh rice rat is the natural reservoir of the Bayou virus, the second most common cause of hantavirus pulmonary syndrome in the United States. Two other hantaviruses, Catacamas virus and Playa de Oro virus, occur in O. couesi in Honduras and western Mexico, respectively, but are not known to infect humans.