Have you ever been in a situation where you are spending time with your special pet and you notice their focus is on something else? You can't quite make out what they're distracted by - until you get closer. Once you are in range you can see what has caused this perturbed behavior. It's a BIG spider! Not just any spider, but a big DEADLY spider. Deadly spiders are not a huge threat in the United States, but there are a few species to look out for. Two of the more common species are black widow spiders and brown recluse spiders. Both species are venomous and can be deadly to humans, horses and pets.
Black Widow
There are a variety of species of black widow spiders found in North America. The appearance of each species varies subtly - but they all are recognizable by their black coloration and a red hourglass pattern on their underbelly. Black widows are not aggressive spiders, but will bite if they feel threatened. Their venom is a neurotoxin that causes paralysis, muscle rigidness, and breathing difficulty. Healthy adult humans and large animals who are bitten may suffer little - but a bite from a black widow could cause death in children and small animals.
Brown Recluse
A brown recluse spider is not as easy to recognize as the black widow. This spider is generally a light brown color with a dark violin shaped spot on its back. An odd characteristic of this particular spider is its set of three pairs of eyes (verses four pairs common in most spiders).
Brown recluse spiders are known to hide during the day in dark crevices and walls of homes, barns and tack rooms. This species is not normally an aggressive spider either, but will bite if threatened. The venom of a brown recluse is powerful hemotoxin and may not be noticeable until a few hours after a bite. This venom is potentially deadly and resulting in necrosis (soft tissue death), but more commonly causes nausea, vomiting, rash and fever.
It is never a good idea to take a risk with poisonous spiders. If you find one in your home, pet living quarters or barn be sure to take action immediately. You can use household pesticides like a spray to get into niches and crevices or a household fogger.