Newly proposed checkerspot critical habitat
The new US Fish and Wildlife proposal for Bay checkerspot critical habitat is a modification of the critical habitat outlined in 2001 (which was sent back to F&W by a lawsuit). A final determination will be made by Aug 14, 2008.
Changes in the critical habitat were made based on decisions about the physical and biological features that are essential to the conservation of the butterfly. Some areas that are non-grassland or extensively developed
were dropped, while a Pulgas Ridge unit was added because it historically supported the Bay checkerspot and could be a stepping stone between the San Bruno Mountain unit and the southern San Mateo County units (Edgewood Park
and Jasper Ridge). In total, the current proposed area is smaller than the 2001 rule by about 4,000 acres, and includes 329 acres (133 ha) at Jasper Ridge.
The following website includes a link to the Federal Register with the revised proposal, which has a fairly detailed discussion of the revised critical habitat units.