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In this lesson, we're going to discuss an uncommon hazard for your pet: venomous spider bites. We'll also be giving you a little information on the three types of venomous spiders you're likely to find in the U.S. At the end of the lesson, we'll provide you with Word about the affects bugs can have on your pet.

Venomous spider bites in the U.S. are not common and this includes those involving pets. In fact, it's very unlikely that you'll ever need to take your pet in to see your veterinarian because of a venomous spider bite. But that doesn't mean it's not possible.

An important thing to note about venomous spider bites and pets is that we don't know if the bites themselves are uncommon, or if those bites are more common than we think, and they simply go unrecognized.

Venomous Spiders in the U.S. to be Aware Of

In the United States, there are three venomous spiders you should be aware of:

  • Brown recluses
  • Hobo spiders
  • Black widows

Each of these venomous spiders carry different concerns and their bites produce different symptoms.

Brown Recluses

Brown recluse spiders are usually between 6 and 20 mm in length (0.24 and 0.79 inches) but may grow larger. While typically light to medium brown, they range in color from whitish to dark brown or blackish gray.

A bite from a brown recluse spider can cause local tissue damage and destruction as well as pain for your pet.

Hobo Spiders

Hobo spiders sometimes build their webs in or around human habitations. The hobo spider lays its eggs in September and they hatch during late spring. They vary considerably in appearance, and identification can be difficult. However, a hobo spider is typically 7 to 14 mm in body length (0.28 to 0.55 inches) and brownish in color.

A bite from a hobo spider causes damage similar to a brown recluse – local tissue damage and destruction and pain – but of the two spiders, the brown recluse is more of a concern.

Black Widows

There are several types of black widow spiders in North America: Southern Black Widow, Western Black Widow, and Northern Black Widow.

Female widow spiders, in general, are typically dark brown or a shiny black in color when they are full-grown, and usually exhibit a red or orange hourglass on the underside of the abdomen. Some may have a pair of red spots or have no marking at all. The male widow spiders often exhibit various red or red and white markings on the upper side of the abdomen.

The venom of widow spiders contains a neurotoxin, which can cause headaches, abdominal pain, and stomach upset. The black widow spider is the one in this group of venomous spiders to be most concerned about.

Pro Tip: Unless you see your pet interacting with one of these venomous spiders, it's probably going to be unlikely that you or your veterinarian will suspect a spider bite, given how uncommon they actually are.

Treatment for Venomous Spider Bites

If your pet gets bitten by one of these venomous spiders, the course of treatment mostly includes supportive care. However, in severe black widow bite cases, there is an antivenom available in the U.S.

A Word About the Affects Bugs can have on Your Pet

Bugs aren't just a nuisance for us humans, they're also a nuisance for our pets. And sometimes, they're more than a nuisance.

Bugs have been known to suck, sting, and bite. Some common pests that your pets may have some trouble with include:

  • Fleas
  • Ticks
  • Wasps
  • Bees
  • Spiders
  • Mosquitos

Dogs seem to suffer more than cats, according to pet expert Cara Armour, perhaps because of their curious nature and how they tend to lead those noses of theirs. Either way, prevention is tricky.

In her story for the ProPetHero blog, Cara writes about how a fun afternoon playing frisbee with her two dogs turned into an opportunity to grab her pet first aid kit and perform back yard triage. Thanks to a wasp nest that wasn't obvious.

One of her dogs was stung on his legs, while the other was stung around her eye. Neither felt particularly great about being stung and Cara had trouble tending to both of them at once.

If you're interested in reading the entire story, you can do so here: Pet First Aid Awareness – Bugs Suck! Cara will also share with you what you can do to treat bug bites and stings (including how she treated those wasp stings) and even how you can help prevent them from occurring in the first place.