Endemic to Mexico where it only occurs on Guadalupe Island and is seriously threatened by grazing goats and fire
Mexico: Baja California Norte, restricted to Guadalupe Island.
The current number of mature trees has been reported differently, but depending on how one defines a mature tree, it seems likely that only between 100 and 200 trees were left at the time the goats were finally eradicated in 2005. Regeneration had started to take effect within enclosures from about 2002 (Junak et al. 2003), and also outside these fenced areas since 2005/6.
Habitat and Ecology
Generally simialr to that of the species but on Guadeloupe Island often associated with Pinus radiata var. binata; the climate is substantially cooler in summer than on the mainland due to frequent fog.
Some plants originating from seed collected on Guadalupe Island appear to be in cultivation in the USA (California).
The decline of the population of mature trees caused by feral goats and fires, and possibly drought, has by all accounts been severe and is likely to have exceeded 70% from the situation about 100 years ago, when goats became established on the island. The goats have now gone, and regeneration is beginning. However, other threats such as fire and draught still remain and could wipe out the fragile remainder of the population.
The situation with this variety is extremely critical due to overgrazing by feral goats. The population may not exceed 200 mature trees in two small, separate stands. Recent fires have destroyed many trees. The devastation of the vegetation, caused by more than a century of overgrazing and browsing by goats, may have lowered the water table in the two locations where the cypresses occur. No permanent residents live on the island, which is visited only occasionally.
The goats are now finally reported to have been eradicated on the island in 2005. This is a major step towards recovery of the population of C. guadalupensis var. guadalupensis. Previously, a few limited areas had been fenced (excluded) in which many of the cypresses occur, enabling regeneration to start.