Romerolagus diazi
volcano rabbit

The volcano rabbit has one of the most restricted ranges of any mammal in Mexico. It is found only in the central part of the Mexican transvolcanic belt. Populations are patchily distributed on slopes south of the Valley of Mexico.

Volcano rabbits are found between 2800-4250 meters in elevation in a special habitat called "zacaton." These are open pine forests with an understory of dense bunch grasses. The substrate is generally dark basaltic rock with patches of deep, dark soil. They also occur in darker, moister, secondary alder forests with a heavy grass-shrub understory.

The pelage is short and dense. The back and sides are yellowish fur mixed with black, the base of the ears are buff colored, the underside is light buff with grey underfur. This is the one of the smallest leporids and has very short ears and a vestigial tail. Measurements: Total length: 275-357mm; Tail: 18-31mm; Ear: 40-45mm; Hind foot: 42-55mm.

Volcano rabbits live in burrows in groups of 2-5 individuals. They are generally active during the evening and early morning. The burrows can be as long a 5 meters and may be as much as 40 cm unerground. The burrow entrance is concealed at the base of a grass clump. Nests are constructed only from April through September. Nests are shallow depressions hidden under a grass clump and lined with fur and plant fragments.

Volcano rabbits, like pikas, give high-pitched calls. As many as five different calls have been described.

Volcano rabbits eat the tender green leaves of grasses, especially Festucas, Muhlenbergia macroura, Stipa ichu, and Epicampes. They also eat young leaves of spiny herbs and the bark from alder trees. During the rainy season, R. diazi eats cultivated oats and corn.

They may do damage to corn and oat crops planted near pine and alder forests.

The genus Romerolagus is monotypic and the three populations of R. diazi have discontinuous distributions. The rabbit has recently (in the past 15-20 years) disappeared from areas of central Mexico where it had previously been reported. The volcano rabbit is threatened by habitat degradation due to over-grazing by cattle and sheep, by overexploitation of timber, and by encroaching agriculture.

This rabbit's dark pelage blends especially well with the volcanic soils of its habitat and may serve to protect it from predators.