Southern Colorado’s Tarantula Mating Season Is Here: What to Expect

Hoping for a fun and unique adventure this fall? Look no further than Southern Colorado, where hundreds of male tarantulas roam the prairie in search of love.

Tarantulas are native to the semi-arid grasslands of Southwestern Colorado, most notably near La Junta in the undisturbed prairie of Comanche National Grassland, and from the Four Corners area to Pueblo. They are seldom seen in the wild for most of their adult life because they live in burrows and ambush prey as it comes across the opening.

From mid-September to early October, mature males, usually around eight to 12 years old, venture from their burrows when temperatures cool off at night to find a suitable female to mate with. Sometimes they roam as far as one mile in a night, which is the equivalent of a human running a marathon, says Maia Holmes, entomologist and education and outreach coordinator for Colorado State University’s Department of Agricultural Biology.

Once they find a burrow, the male taps his feet at the opening and performs other elaborate mating rituals to alert the female to his presence. Once the deed is done, the male must skitter away quickly, or the female might turn him into a late-night snack.

“It’s a bug-eat-bug world out there, so if that’s an option, a female will take it,” Holmes says.

Males use up to 40% of their metabolic energy mating, so even if they survive, they die soon after. Males typically live only 8 to 12 years, while females can live past 20 years. They typically inhabit one burrow for most of their lives. The most common species in Colorado is the Oklahoma Brown tarantula, also known as the Colorado Brown tarantula.

Anecdotally, scientists suspect that tarantula populations are decreasing due to climate change, wildfires and habitat fragmentation, Holmes says. However, tarantula populations haven’t been extensively studied, so scientists don’t know how severely the population has declined.

Tarantulas are part of the prairie’s delicate and intricate ecosystem, providing food for other animals and soil nutrient cycling. As tarantula populations decline, it disrupts the survival of other animals that depend on them.

Landowners can leave native prairie habitat intact to protect these furry arachnids. Everyone can support national parks and grasslands and legislation that supports native habitats and wildlife, Holmes says.

The best time to look for tarantulas is an hour before sunset, usually around 5:45 to 6 p.m.

Outside of Comanche National Grassland, ideal places to look for males are south of La Junta on Highways 10, 350 and 109, and the county roads in between. Other popular sites include Vogel Canyon (15 miles from La Junta), Sierra Vista and Timpas Picnic Area (about 20 miles from La Junta along Highway 350) and Delhi (36 miles from La Junta on Highway 350).

Just a short drive from La Junta, Vogel Canyon also offers picnic shelters, a vault toilet and hiking trails with varying difficulties and lengths.

If you venture on a tarantula expedition, make sure to watch for tarantula road crossings, follow Leave No Trace guidelines and do not pick up, touch or disrupt tarantulas in their native habitat, Holmes says.

You can also register for a guided tarantula tour through La Junta’s Tarantula Festival at visitlajunta.net/tarantula-fest.