Tarantulas are residents of Kansas, surprising many who associate these large spiders only with more arid, southwestern states. These native arachnids are a natural part of the state’s ecosystem, particularly in the southern and western regions. Kansas is near the northern extent of their natural geographic range in the central United States. Though typically hidden, their presence becomes noticeable during a specific time of year when they emerge.
Identifying the Kansas Tarantula
The single species of tarantula found in Kansas is the Texas Brown Tarantula (Aphonopelma hentzi). It is also called the Oklahoma Brown Tarantula, reflecting its wide distribution across the central and southern U.S. Aphonopelma hentzi is the largest spider in Kansas, with a leg span reaching up to five and a half inches in mature individuals.
Their coloration ranges from dark brown to black, often featuring a bronze or brass-colored carapace (the upper shell of the cephalothorax). The body is covered in velvety, dense hair, giving them a fuzzy appearance. A notable difference exists between the sexes, known as sexual dimorphism.
Female tarantulas are generally more robust and heavier-bodied than males, and they can live for twenty years or more. Males are typically lankier with longer legs and have a significantly shorter lifespan, often lasting only a few years.
Where and When They Are Seen
The Texas Brown Tarantula population is most robust in the southern tier of Kansas counties, extending northward into the central and western parts of the state. Healthy populations exist in the Red Hills region near Medicine Lodge and the prairie and wooded hills of the southeast, such as Chautauqua and Elk counties. These spiders thrive in open, dry habitats like grasslands, prairies, and scrublands.
For most of the year, these tarantulas remain hidden as they are terrestrial burrowers, constructing silk-lined tunnels or inhabiting abandoned rodent holes. Females rarely leave the safety of their burrows, which serves as a secure place to ambush prey and raise their young. They are primarily nocturnal hunters, emerging at night to capture insects and other small invertebrates.
The most frequent sightings occur during the mating season, from late August through October. Mature males leave their burrows to search for females, a behavior often called the “wandering season.” These males are often seen crossing roads and open areas, sometimes even during the daytime, as they follow pheromone trails left by receptive females.
Temperament and Safety Concerns
Despite their intimidating size, Aphonopelma hentzi is a relatively docile and non-aggressive species. Their primary instinct when disturbed is to retreat into their burrow or flee. A tarantula will only bite if it feels seriously threatened and has no other option, such as when handled or accidentally stepped on.
Before biting, an aggravated tarantula often displays a defensive posture, raising its front legs and showing its fangs as a clear warning. Another defense mechanism involves urticating hairs—specialized barbed bristles on their abdomen that they flick into the air using their legs. These hairs can cause skin irritation, itching, and significant discomfort if they enter the eyes.
The venom of the Texas Brown Tarantula is mild and is not medically significant to humans. A bite is typically compared to a common bee sting in terms of pain and localized reaction, including redness and minor swelling. Allergic reactions are the main concern, and severe symptoms warrant immediate medical attention. Observing these spiders from a distance is the best approach, and they should never be handled.