Hobo Spider: All You Need to Know for Safety and Prevention

The hobo spider, scientifically known as Eratigena agrestis, is a member of the funnel-web spider family Agelenidae. These spiders are known for their long legs and swift-running abilities, which allow them to skillfully construct funnel or tube-shaped retreats in various habitats. Commonly found in Europe and some parts of the United States, hobo spiders prefer places like turf, log piles, rock piles, and areas around homes and yards.

There are a few misconceptions about the hobo spider’s behavior and toxicity. Contrary to popular belief, their venom is not more toxic than that of other spiders, and they exhibit no more aggression towards humans. Instead, these misunderstood arachnids tend to reside in dark, moist areas such as basements and window wells.

Identification of hobo spiders can be tricky since they share similarities with several other species. To accurately identify a hobo spider, one must be aware of certain diagnostic anatomical features. For example, hobo spiders possess eight eyes arranged in two rows, which distinguishes them from other funnel-weaving spiders.

Hobo Spider Identification

Appearance and Markings

The Hobo Spider (Eratigena agrestis) has a few key characteristics to help with identification. Some of these are:

• Brown color
• Oblong abdomen
• Long legs

Hobo spiders have distinctive markings on their abdomen, including a pattern that resembles a chevron. These markings are not always easily visible.

Eyes and Spinnerets

All funnel-weaving spiders, including the hobo spider, have eight eyes arranged in two rows. They also possess spinnerets, which are silk-producing organs located at the rear of their abdomen.

Comparison with Other Spiders

The hobo spider is often mistaken for other spider species, such as the brown recluse or the giant house spider. A comparison table can help clarify the differences:

Keep in mind that hobo spider bites are rarely dangerous to humans, in contrast to the brown recluse and black widow spiders. Additionally, hobo spiders are poor climbers and are usually found near the ground in dark, moist areas, making them less likely to come into contact with humans.

Habitat and Behavior

Outdoor Habitations

The hobo spider, also known as Eratigena agrestis, is a member of the Agelenidae family and is native to Europe. It was introduced in the Pacific Northwest region of the United States, including states like Washington, Idaho, Utah, and Oregon ¹. Hobo spiders build their funnel-shaped webs at ground level, often in locations close to human habitation. These spiders can be found in the following outdoor habitats:

• Woodpiles or log piles
• Rocks and debris
• Railroads and nearby vegetation

These spiders’ webs are used to catch prey, and they are mainly active at night.

Adapting to Indoor Environments

Sometimes, hobo spiders find their way into indoor spaces. They can survive a variety of environments, but can be considered pests when they enter homes or buildings. Below are the common reasons for their indoor presence:

• Seeking shelter from cold or harsh weather conditions
• In search of food (insects or other small arthropods)

If you find a hobo spider indoors, you can either vacuum them up or carefully catch and release them outside.

Note: Although hobo spiders are not aggressive and their venom typically does not cause any severe symptoms in humans, it’s still best to handle them with caution.

In conclusion, hobo spiders are adaptable arachnids that can be found in both outdoor and indoor environments. Being aware of their habitats and behavior can help in identifying and managing their presence in and around your home or property.

Reproduction and Mating

Mating Season

Hobo spider mating season typically occurs in late summer and early fall¹. During this time, both male and female spiders are more active and likely to be found searching for mates.

Mate Searching

Male hobo spiders search for potential mates by wandering around and using their spinnerets to leave a trail of silk. Upon finding a female’s web, the male will often enter the web’s escape tunnel to verify if a mate is present. Some characteristics of hobo spiders include:

• Body length: Males are 7-11 mm, and females are 11-14 mm²
• Long legs
• Funnel-shaped webs

When a male spider successfully locates a receptive female, a courtship process occurs, involving various physical and chemical signals. An example of the mating process can be seen in how the male uses his palps to transfer sperm to the female³.

Comparison of Hobo Spider and House Spider:

Bites and Venom

Symptoms of a Hobo Spider Bite

Hobo spider bites can cause a variety of symptoms. Some of the most common symptoms include:

• Pain: Radiating pain from the site of the bite
• Redness: A reddish to purplish color around the bite area
• Swelling: Inflammation and possible blistering
• Muscle pain: Cramping or twitching in the affected area
• Headaches: Persisting for 2 to 7 days and resistant to pain relievers ¹

It’s important to note that while these symptoms can be concerning, hobo spider venom is not considered toxic to humans in its native European habitat ².

Treatment and Precautions

If you suspect a hobo spider bite, it is crucial to seek medical attention for proper diagnosis and treatment. The Centers for Disease Control and Prevention (CDC) and other experts recommend the following precautions:

• Cleaning: Gently clean the bite area with soap and water
• Ice: Apply ice to reduce swelling
• Elevation: Keep the affected area elevated above heart level
• Pain relief: Take over-the-counter pain relievers as needed
• Medical attention: Consult a doctor if the symptoms worsen or do not improve within a few days ³

Comparison Table: Hobo Spider & Giant House Spider

Following these steps and being cautious when encountering spiders can help minimize the risk of bites and ensure proper treatment if bitten.

Preventing and Managing Hobo Spider Infestations

Exclusion Techniques

• Seal cracks and crevices: Hobo spiders can enter homes through small openings. To prevent their entry, seal exterior cracks and crevices with caulk or weather stripping.
• Install door sweeps: Place tight-fitting door sweeps at the base of all exterior doors to block spider entry.
• Use window screens: Ensure that windows and vents have proper screens in place to prevent entry.

Sanitization and Clutter Reduction

• Eliminate clutter: Reduce hiding places for hobo spiders by removing clutter and debris from basements, garages, and other low-traffic areas.
• Keep areas clean: Vacuum regularly to remove spiders, webs, and egg sacs. Maintain a clean environment to reduce the number of pests that hobo spiders prey on, such as flies and roaches.
• Landscaping: Maintain a tidy outdoor environment by trimming trees and shrubs away from the home and removing piles of wood or debris.

Use of Traps and Insecticides

• Sticky traps: Place sticky traps indoors near entry points and corners to catch hobo spiders. Replace traps regularly as they become filled with spiders or lose their stickiness.
• Insecticides: Apply insecticides directly on hobo spiders for effective management. Read and follow instructions carefully for safe application and keep in mind that insecticides alone may not solve the problem completely.

PROS:

• Effective in reducing spider population
• Immediate impact
• Can be targeted to specific problem areas

CONS:

• Requires ongoing maintenance
• Potential harm to beneficial insects
• May not completely eradicate infestation

By combining exclusion techniques, sanitization and clutter reduction, and the use of traps and insecticides, you can effectively manage and prevent hobo spider infestations in your home.