Southeast Colorado is home to thousands of the creepy crawlers. Every year in August and September, the male tarantulas leave their burrows in masses and begin searching for a mate.
Scripps News Denver reports that the annual event is often mistaken as a migration because the spiders are more visible than normal and appear to be walking to a desired destination.
That desired destination, in this case, is a female tarantula's burrow, so the pair can breed.
While many people would like to avoid a run-in with a tarantula, the annual event has generated a lot of interest among nature watchers. In fact, the town of La Junta, east of Pueblo, invites people to visit and watch the spiders on their journey.
The most common type of tarantula people can expect to see is the Oklahoma brown.
"This dark brown to black species of the genus Aphonopelma is common here because its females prefer to make their burrows in the plentiful undisturbed prairies on the Comanche National Grassland of Southeast Colorado," La Junta officials say.
Female tarantulas have a lifespan of about 25 years, while their male counterparts typically only live for about 10 years.
