Brown Recluse Spiders in Washington State: How to Identify, Avoid, and Treat Bites

Brown Recluse Spiders in Washington State

The brown recluse spider, also known as the violin spider or Loxosceles reclusa, is one of the most dangerous spiders in the United States. This spider gets its name from the violin-shaped marking on its cephalothorax. While brown recluse spiders are most common in the southern and central United States, they have been spotted in Washington state on rare occasions.

Appearance and Identification

Brown recluse spiders are usually between 6-20 mm (0.25-0.8 inches) in body length. Their legs span approximately 2.5-4 cm (1-1.5 inches). They are a light to medium brown color with a darker violin-shaped marking on the cephalothorax (fused head and thorax). The neck of the violin points toward the abdomen. These spiders have six equal-sized eyes arranged in three pairs in a semicircle pattern. Their eyes reflect light, helping identify them at night.

One key identifiers of a brown recluse spider is that they have no spines on their legs and only six eyes (most spiders have eight). Their legs are also very long compared to their body size. Brown recluse spiders can easily be confused with other harmless spiders, so it's important to look for the telltale violin marking and other distinguishing features when trying to identify one.

Venom and Bite

The brown recluse has a cytotoxic venom that can cause serious wounds in humans. Their venom contains the toxin sphingomyelinase D, which breaks down cell membranes and tissues. However, the brown recluse typically only bites when threatened or pressed against the skin.

Bites usually occur on the limbs or torso. At first the bite site is painless, but pain and itching develops 2-8 hours later. A small white blister forms surrounded by a large area of purple, red or brown discoloration. The damaged tissue then becomes hard and forms an eschar that eventually sloughs away, leaving an open wound that can take weeks or months to heal.

While extremely rare, severe reactions can occur including fever, chills, dizziness, nausea, and systemic injury to internal organs. Seek immediate medical care if bitten by a brown recluse spider.

Habits and Behavior

Brown recluse spiders build irregular webs in dark, secluded locations like attics, crawlspaces, cellars, and sheds. They are nocturnal and actively hunt at night. During the day, they hide in piles of rocks, rotting logs, rubble, and other undisturbed areas.

The brown recluse thrives in hot, dry conditions. They avoid the sunlight and are rarely seen out in the open. They are also slow-moving compared to other spider species. Still, they can move quickly over short distances, and will bite if pressed up against human skin.

Range and Distribution in Washington

The natural range of the brown recluse spider spans across the southern, central, and parts of the western United States. They are most common in Oklahoma, Texas, Arkansas, Missouri, Kansas, and Louisiana. Established populations also occur in parts of Indiana, Ohio, Kentucky, Tennessee, Georgia, and Alabama.

In the western states, brown recluse populations are much less dense and scattered. A few areas of southern California, southern Nevada, southwestern Utah, western New Mexico, and central Arizona have recorded populations. There have also been rare documented sightings in Washington state.

While the climate of Washington is normally too cold and wet for the brown recluse to thrive, global warming may allow small isolated populations to persist. Most sightings in Washington occur near warehouses, shipping containers, and boxes of goods transported from southern states. The spiders are accidental stowaways and cannot survive Washington winters outdoors.

How to Avoid Brown Recluse Spiders

To reduce the risk of encountering brown recluses in Washington, follow these tips:

• Clear away debris piles, leaf litter, and clutter around the home, especially in crawl spaces and cellars.
• Store boxes of items from southern states outside of the living area.
• Inspect or shake out clothing, shoes, and bedding that have been sitting in piles or boxes.
• Install sticky traps in undisturbed corners and crevices to monitor for spiders.
• Seal cracks in foundations and openings around windows.
• Wear protective clothing like gloves, long sleeves, and pants when handling items stored for long periods.

Being aware of the potential presence of brown recluse spiders is key. Their populations are sparse and isolated in Washington. With proper care and home maintenance, the chances of encountering one is extremely low.

What to Do if Bitten

Seek medical attention immediately if bitten by a spider you suspect is a brown recluse. Try to safely capture the spider in a container to show the doctor for identification.

Wash the bite area with soap and water and apply an antibiotic ointment. Apply an ice pack wrapped in cloth to reduce swelling and pain. Do not apply heat, cut into the wound, or apply baking soda, as these can increase tissue damage.

Signs of a severe reaction include fever, chills, joint pain, vomiting, headache, and/or a spreading rash. Seek emergency care right away if any of these symptoms occur.

While the vast majority of suspected brown recluse bites do not come from this spider, it's important not to take any chances. Always have a doctor assess the bite just in case it was from this venomous spider.

Conclusion

Brown recluse spiders are uncommon in Washington state and established populations do not exist here due to the unsuitable climate. Most sightings occur in isolated incidents near warehoused goods from southern states. Still, due to the dangerous venom of the brown recluse, caution should be taken around areas these accidental stowaways may hide.

Proper home maintenance, avoidance of clutter, and careful inspection of stored belongings can greatly reduce the chances of encountering one. Seek immediate medical attention if you suspect you have been bitten by this venomous spider.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.