The Las Vegas Valley provides crucial habitat for the desert tortoise, but had been facing powerful development pressure from Las Vegas, which was one of the fastest-growing cities in the United States for many years.Formally approved by the USFWS in August 1991, the HCP (ed. Habitat Conservation Plan) permitted 22,352 acres of development to occur in the Las Vegas Valley in exchange for the establishment of a 400,000-acre desert tortoise preserve. Earlier, in a related action, the Conservancy helped settle a major lawsuit over the listing of the species, which has resulted in over $1 million being allocated to desert tortoise research.
Clark Countys Short-Term Desert Tortoise Habitat Conservation Plan (HCP) was a landmark mitigation agreement developed by The Nature Conservancy and other conservation partners to assure the preservation of the desert tortoise while allowing development in the Las Vegas Valley to continue.
Tortoises are an indicator species, holding that if the animal is having a hard time surviving for some reason, other animals are as well.
Losses in tortoises are due to a respiratory disease, exacerbated in part by the release of captive tortoises into the wild.
http://www.csmonitor.com/1992/0212/12081.html
http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/nevada/placesweprotect/desert-tortoise-habitat-conservation-plan.xml
These tortoises were doing so poorly a veterinarian, Dr. Jarchow, was consulted. He reported all six specimens were suffering from osteoporosis caused by a protein deficiency in their diet. Dr. Jarchow examined five specimens from the same mountains that shared their range with cattle. He reported these specimens were all healthy and well nourished.
The historical record proves conclusively that tortoise thrive when cattle are on the range with them and without cattle grazing they are always malnourished and unhealthy and their numbers plummet.
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