It's mid October now and the La Junta area has already received one light snow. Nothing stuck, of course, but with the changing season one might think that their chance to witness Southeast Colorado's famous tarantula "migration." Well, one would be wrong: Michelle Stevens, zone archaeologist for the U.S. Forest Service, says that the media got an early jump on the seasonal spectacle.
"It's actually mid-September to the end of October, typically, with a little buffer on each side," Stevens told the Tribune-Democrat.
The "migration" isn't really a migration either, Stevens said. Mid-September to October is the Oklahoma Brown Tarantula's typical mating season, which explains why the large spiders show up so frequently during this time. The spiders observable during this "migrational" period are almost guaranteed to be male, as they are seeking females to mate with. The males are likely seven to 10 years old and tend to die after mating. The females, however, can live up to about 40 years.
There isn't much research on the precise travel habits of spiders in the area of Comanche National Grassland area, where Stevens mostly works, but Stevens said they likely don't travel further than a mile.
"We are typically recommending that visitors look for them on the roads because that's where they're most visible.," Stevens said. They can walk around on their own and that's fun, but again, early morning or late afternoon just before dusk or just after dusk are good times to see them."
This year, Stevens has observed more tarantulas near Timpas, but she's also seen plenty on local county roads and even on San Juan Avenue near the edge of La Junta. She recommends that anyone planning to search for tarantulas along the grassy shoulders of country roads should be prepared with close-toed shoes and pants. Particularly for dusk excursions, Stevens recommended that people bring water, a cellphone and a flashlight with them.
Stevens also urged caution when driving through the grasslands at night: The area has open ranges, meaning cattle can and will be on and along roads at times.
"There could be cows on the road, and a black cow is really hard to see on the road," said Stevens. "They don't come with reflectors.
"Be careful. Slow down, be careful about where they park. Look for traffic. If we're looking for (tarantulas) in the road we want to make sure there's not (incoming traffic). It sounds obvious, but-"
Stevens said that spiders, of course, are not the only creatures to inhabit the grasslands of Southeastern Colorado. Snakes live amongst the grasses and in burrows similarly to the tarantulas themselves. While the spiders are shy during midday, at any time of day, Stevens said, one can find webbing along the ground. The webbing is not always indicative of the Oklahoma brown tarantula - other spiders weave webs as well, of course - but if the webbing is situated over a hole about the size of a half dollar, then that's a good sign it belongs to an Oklahoma brown.
The tarantulas build their burrows by digging an approximately 12-inch tunnel. At the end of the tunnel is a chamber where the tarantula rests. When hunting, the tarantulas will web their prey and take them back down below.
"That's why the agricultural land isn't prime (to find tarantulas), because that plowing destroys that habitat, and that's why you need to get out of those areas," Stevens said. "But these burrows, at all times of day there's a good chance. A lot of the wildlife on the Comanche grassland and in this part of the state occurs underground."
Visitors to the grasslands of Southeastern Colorado might also encounter the Oklahoma brown tarantula's greatest natural enemy: The tarantula hawk.
"They are big wasps about this size," said Stevens. She held her fingers about two inches apart. "What they do is they sting the tarantula, and they take it down into the wasp's nest and lay eggs on the tarantula's back."
The tarantula is immobilized by the wasp's venom. The wasp's eggs hatch only a few days later, larvae feast on the potentially still living spider.