When the summer sun scorches the landscape and surface temperatures soar above 110°F, most creatures seek shelter. But for the desert tortoise, one of the region’s most resilient animals, survival is all about adaptation.

These slow-moving reptiles have evolved extraordinary ways to endure life in one of the harshest climates in North America. Here’s how they do it.

Underground Architects: Desert tortoises spend up to 95% of their lives in burrows they dig into sandy or rocky soil. These underground shelters act like natural air conditioners, staying cooler in the summer and warmer in the winter than the surface. Depending on the season, tortoises may use shallow burrows for basking or deeper ones to ride out the intense summer heat.

Beating the Heat with Estivation: When temperatures spike, and water becomes scarce, desert tortoises enter a dormant state called estivation—a kind of summer hibernation. During this time, their metabolism slows dramatically, helping them conserve both energy and water. They’ll remain in their burrows for weeks or months, waiting for cooler temperatures and seasonal rains to return.

Timing Is Everything: Rather than braving the intense midday heat, desert tortoises are most active during spring and fall, limiting their movement to early mornings and late afternoons in warmer months. This crepuscular activity pattern minimizes exposure to the sun and reduces the risk of overheating or dehydration.

Internal Water Tanks: Desert tortoises have a fascinating adaptation that allows them to store water in their bladders, sometimes for months. This internal reservoir can be reabsorbed as needed during droughts. One spring rainfall or a feast of wildflowers can replenish their water stores for an entire season. It’s why handling wild tortoises is discouraged; when frightened, they may release their stored water, potentially threatening their survival.

Built-In Protection: Their thick, scaly skin reduces moisture loss. At the same time, the tortoise’s high-domed shell provides both protection from predators and insulation from the sun. It also shades internal organs and reflects radiant heat, further protecting the animal from thermal stress.

Eating for Hydration: Spring is feast time and Desert tortoises consume water-rich plants like grasses, wildflowers, and succulents to build up both nutrient and water reserves. This adaptation is especially vital before summer dormancy, when water sources may vanish entirely.

Efficient Waste Management: Unlike humans, desert tortoises don’t excrete liquid urea. Instead, they produce uric acid, a pasty substance that conserves water. This remarkable kidney efficiency is a key to their success in such a dry ecosystem.

A Keystone of the Desert: Beyond their survival, desert tortoises play a crucial role in the desert ecosystem. Their burrows provide homes to over 40 other species, including burrowing owls, snakes, and insects. Protecting these creatures helps safeguard an entire desert community.

A Conservation Milestone: Draft General Conservation Plan: In late 2024, the U.S. Fish and Wildlife Service released the Draft General Conservation Plan (GCP) for the Desert Tortoise in California. This comprehensive strategy provides a framework under the Endangered Species Act, helping regulate development while enforcing conservation standards.

Key highlights include:

• Standardized mitigation measures to reduce habitat fragmentation on non-federal lands
• A focus on long-term habitat connectivity to support tortoise migration and gene flow
• Requirements for monitoring and adaptive management of tortoise populations

This Plan is especially relevant to Anza-Borrego Desert State Park, where habitat corridors and protected land buffers are essential to maintaining viable desert tortoise populations. As development pressures increase and transmission projects, such as the Imperial Valley to San Onofre 500kV line, loom, this framework becomes even more vital.

ABF supports science-based conservation planning, and this draft represents a critical tool for protecting species like the desert tortoise before it’s too late.

What You Can Do: If you see a desert tortoise in the wild—observe, but don’t touch it. And support conservation efforts that protect these extraordinary survivors and the fragile habitat they call home.

📄 Read the Draft General Conservation Plan for the Desert Tortoise in California