Tortoise protection in Mojave Desert must be a priority

[faze]

Date: Apr 07, 2004 - 11:59 AM
By Chris Benda

Head out into the desert 25 years ago and you would likely find a desert tortoise among the creosote scrub. With thousands of tax dollars spent each year on surveys for the desert tortoise, Gopherus agassizii, our state reptile is becoming increasingly harder to find.

Over 100 environmentalists, land managers, and scientists met in Las Vegas, Nevada last month at the 29th annual Desert Tortoise Symposium to discuss the latest news regarding conservation of the desert tortoise.

The conference, which is organized by the Desert Tortoise Council, focused on ways to halt the declining desert tortoise population. One way is possibly upgrading the desert tortoise, now a federally listed threatened species, to endangered status.


It is very difficult to achieve the endangered designation for a species, especially with the current administration in the White House. Some may argue that the classification is not justified because although the western Mojave tortoise population appears to be decreasing, surveys suggest that tortoise decline in the rest of their range is not as drastic.

Some scientists lamented that because their range includes the tortoises in Arizona, the overall number of tortoises is overstated. They assert that any tortoise which cannot reproduce with the Mojave population because of the Colorado River barrier, should not be counted with the Mojave population.

Although the Mojave desert tortoise is classified as a subspecies, some scientists assert the Mojave tortoises should be separate species, and thus be granted endangered status.

The symposium also presented some exciting research studies underway with desert tortoises. Andrew Walde and his team are conducting an automated radio telemetry experiment in the critical habitat south of Fort Irwin.

They have mounted 40 transmitters on the shells of adult tortoises. The transmitters send a signal to receiving stations and from this information, Mr. Walde says, researchers can determine if the tortoises are active or inactive, or whether they are aboveground or in burrows.

This is useful because one can determine what a tortoise is doing from a remote location, 24 hours a day and more than one tortoise at a time can be monitored by one person.

Ecologist Mark Massar at Fort Irwin states this data is valuable information for land management.

Wildlife Detector Dogs, based in Bakersfield, made another fascinating presentation. He has trained dogs to recognize the scent of desert tortoises with the intention of using them to conduct surveys for desert tortoises.

This is highly applicable because experienced biologists have only their eyes to utilize for tortoise identification. This news may cause one to raise an eyebrow, as the Recovery Plan for the desert tortoise includes, "prohibiting uncontrolled dogs."

However, a properly trained dog does not care about the tortoise, and thus will not hurt it, but only cares about the scent and the subsequent reward.

The reasons for the decline in desert tortoises in the western Mojave region all relate to increasing human activity in the desert and its proximity to the Los Angeles area.

This includes unauthorized OHV routes, trash dumping, collecting of tortoises, releasing of diseased tortoises, and increasing populations of predators, like coyotes, feral dogs, and ravens.

These predators have experienced a dramatic increase in population size due to human subsidies, mainly from trash and water sources.

No easy answer exists to balance human activity in the desert and the conservation of the ecosystem. However, scientists warn that inaction will inevitably result in the loss of this unique and slow-moving creature.

Chris Benda is a freelance writer who lives in Barstow.