Tarantulas are found in San Diego, forming a natural part of the local ecosystem. These large, often hairy spiders are present across various habitats within the county. While their appearance might seem imposing, understanding their presence and behavior helps residents coexist peacefully with these native arachnids.
San Diego’s Tarantula Residents and Their Homes
San Diego County is home to several tarantula species, including the California Ebony Tarantula (Aphonopelma eutylenum) and the San Diego Bronze Tarantula (Aphonopelma reversum). The California Ebony Tarantula ranges from light tan to deep black, while the San Diego Bronze Tarantula is brownish. Both species are substantial, with adult females reaching a leg span of up to 5 inches (13 cm).
These tarantulas prefer semi-arid environments and are terrestrial burrowers, constructing silk-lined homes underground. Their habitats extend across San Diego’s diverse landscapes, including coastal sage scrub, chaparral, grasslands, and desert areas. They are often observed in undeveloped open spaces and rural or suburban communities, particularly in eastern parts of the county like El Cajon, Ramona, Poway, and Alpine. While usually hidden in their burrows, male tarantulas become more visible during mating season, from August through November, as they search for females.
Understanding Tarantula Behavior
San Diego’s native tarantulas are docile creatures that prefer to avoid confrontation. They are not aggressive and would rather retreat or hide from humans than bite. Tarantulas are nocturnal hunters, emerging from their burrows at night to prey on insects, other spiders, and small lizards. Increased daytime sightings during late summer and fall are almost exclusively male tarantulas roaming in search of mates.
Tarantula venom is mildly toxic to humans and not medically significant. A bite from a San Diego tarantula is often compared to a bee sting, causing localized pain, redness, and swelling. Allergic reactions are rare but can occur. As a defensive measure, San Diego tarantulas possess urticating hairs on their abdomens. When threatened, they flick these tiny, barbed hairs into the air, which can cause irritation, itching, and discomfort upon contact with skin or mucous membranes.
Safe Encounters with Tarantulas
Observing tarantulas from a distance is the safest approach. Avoid attempting to handle them, as provocation can lead to a defensive bite or the release of irritating urticating hairs. These spiders are not considered pests and contribute to the local ecosystem by controlling insect populations.
If a tarantula enters your home, safe relocation is recommended. Gently guide the tarantula into a cup or container and release it outdoors in a natural area, such as a nearby open space. If the tarantula exhibits defensive posturing, like rearing up on its hind legs, give it space until it calms down before attempting relocation. For those uncomfortable with direct contact, local animal control services can assist with removal.