Stop it! You're driving me crazy! There are no populations of Brown Recluse Spiders in California period! No matter what the news articles with all their hype say, no matter what a doctor tells you about a spider bit, there are no experts in the field of entomology that will tell you this spider has established it’s self in California. You see, the brown recluse is native to the southeast. It has only been seen in Southern California in association with people and goods being transport from that area into California. Even with these finds no established populations of these spider has ever been found here.
But there is one of the brown recluse relatives that are native to Southern California. The native species that has been seen in small groups is the Desert Recluse. You will find this spider on the outskirts of San Clemente, San Juan Capistrano and all along the foothill areas of Orange County as well as Temecula, Murrieta and Lake Elsinore in Riverside County. It’s also found along the foothills of that area. But it is mainly found in the southern deserts of California, in the eastern parts of the state. Recluses in general are found in cracks and crevices and under rocks. They have very much benefited from human-altered environments where they are readily found under trash cans, plywood, traps, or rubber tires, in boxes, etc. They are often found in association with humans and therefore are considered "house" spiders back east. In the southeast the brown recluse is called the picture spider because it is often found behind pictures hanging on walls.
Several characteristic of these spiders is that in the right environment their populations are usually very dense. If you find one there are more nearby. Unlike many other spiders that disperse by either migrating or being carried by air currents (called ballooning) when small, recluse spiders can expand only outside their native range as a result of human intervention. Like I said earlier, the few brown recluses that have been collected in Orange County and Riverside were typically found in facilities that receive goods from out of state or are unintentionally transported by people who have moved from the South East.
Considering that brown recluse spider bites are not common in the Southeast where they cohabit with people, it is clear that Orange County does not have anywhere near sufficient populations of any recluse spiders to be responsible for the number of cases or illnesses that are attributed to them. All these spiders have the venom that is capable of causing skin lesions. The desert recluse spider's venom is similar to that of the brown recluse and should be considered of equal potency.
The Chilean recluse, which is only in Los Angeles County, supposedly came here on ships docking in the LA Harbor. It has venom more potent than the others. The vast majority of bites from this type of spider heal very nicely without medical intervention but you should always see a doctor after any spider bite. There is still not one proven death from a recluse bite. While there are several highly probable deaths reported in children, these are extremely rare occurrences, about one every decade or so. But as of today no verified bits from this spider have been reported in either Orange County or Riverside County. David Wheeler, WHEELER'S PEST CONTROL,
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