Desert Tortoise at Marine Corps Air Station Ground Combat Center (MCAGCC) Twentynine Palms

UNITED STATES

05.24.2021

Courtesy Story

Marine Corps Installations Command

On April 5, 2021 the Tortoise Research and Captive Rearing Site (TRACRS) at Marine Corps Air Ground Combat Center (MCAGCC) Twentynine Palms released a group of 98 juvenile desert tortoises into the wild. The tortoises were protected and raised in the TRACRS facility and were monitored as part of the MCAGCC translocation program.

In 2006, MCAGCC Twentynine Palms began the headstart program to rehabilitate the desert tortoise , a threatened species that lives in and around the base. The goal is to bolster the natural population, which has declined 50-90% in the Mojave Desert due to a wide range of threats, including ravens, coyotes, habitation degradation, disease, road mortalities and invasive plants.

A major component of the program is headstarting , which is when pregnant tortoises are brought to the facility to nest. The nests are cared for while the eggs incubate. This gives the baby tortoises the opportunity to hatch in a protected environment. It also allows them to grow larger with predator-resistant shells before being released into the wilderness as juveniles.

“We’ve been extremely successful at being able to headstart the tortoise in that we have a 96% annual survivorship of animals inside the facility,” said Brian Henen, Ecologist at MCAGCC Twentynine Palms. “If you compare that to the wild, [the survival rate] is less than 50% in the first year, so we have an extremely high survival rate compared to what one would see in the wild.”

The tortoises are tagged and tracked over several years to monitor their growth, movements and survival rates. The research shows scientists which methods work best for raising baby tortoises, and this information benefits other installations that protect the desert tortoise, such as Fort Irwin, Edwards Air Force Base, Naval Air Weapons Station China Lake and Marine Corps Logistics Base (MCLB) Barstow.

In 2013, MCAGCC Twentynine Palms acquired 123,000 acres of land, including land that was home to the tortoises. Based on an Environmental Impact Statement published by the Navy in 2012 and other federal guidelines passed in 2013, Twentynine Palms had to relocate more than 1,000 adult tortoises to other areas of the base that would not be affected by Marine Expeditionary Brigade training. This has presented a challenge to both training and the headstart program.

“If we are able to better manage the landscape, then we can actually liberate [the] habitat or areas that the Marines could train more liberally or more freely,” said Henen. “We are also protecting the tortoise, including areas that are on the periphery or off of the installation.”

The headstart program is managed by the MCAGCC Environmental Affairs Division and has partnered with other local organizations, such as the United States Fish and Wildlife Services in California and the University of California Los Angeles.

“This collaboration makes the program successful for the recovery of the species, and helps support training aboard the installation,” said Henen.

Since its creation, the TRACRS program has hatched 450 eggs, raised 550 juvenile tortoises from the expansion area and released 234 tortoises to the wild.

• Date Taken: 05.24.2021
• Date Posted: 05.24.2021 13:34
• Story ID: 397232
• Location: US