You could call Louis Coticchio âSpider Manâ, but youâre more likely to find him crawling under houses than climbing up skyscrapers. Heâs a man with a mission: debunking the myth that brown recluse spiders in Florida cause horrifically painful bites that necrotize into life-threatening wounds.
âIn the first place, only about 100 recluse spiders were verified between 1904 and 2018, so less than one spider a year,â Coticchio said. âAnd then, my most recent experiment shows that Mediterranean recluses â the species most likely to be seen in Florida â are extremely reluctant to bite humans, even when handled.â
A student at the ±«Óătv (±«Óătv) with 25 years' experience handling animals, Coticchio has spent the last four years traveling the state looking for recluse spiders, usually following reports of residents being bitten.
âThe funny thing is that Iâve found breeding populations of recluse spiders in 20 locations in Florida, where no one has ever experienced a bite, sometimes after cohabiting for 10 to 20 years,â he said. âBut no recluses were found at the other 107 locations Iâve visited where people claim to have been bitten or seen a recluse."
Itâs almost the stereotypical chicken-and-egg situation, only backward. Someone gets bit by something, and everyone blames it on a brown recluse. That makes it even more likely that the next time someone gets bit, it must have been another recluse. The trouble is that there is no way to scientifically verify that the bite actually came from a recluse spider.
Coticchioâs new Facebook page, the , includes contributors from a âwhoâs-whoâ of experts in the world of venomous spiders. âWeâre trying to dispel some of the myths about not just recluse spiders, but most spiders living on this planet. While some species of spiders may be more defensive than others, spiders are not out to get you,â he said.
âLou has an extraordinary passion for spiders,â said Dr. Debi Cassill, his lead research advisor in ±«Óătvâs Department of Integrative Biology. âWithin the first five minutes of our meeting, I was âtwo-thumbs upâ about his research ideas and invited him to use my lab over the summer for whatever project he wanted to do.â
After nine years as a zookeeper specializing in venomous animals and having crawled under houses in nearly every county in Florida searching for spiders without a single bite, Coticchio was comfortable saying recluse spiders arenât likely to bite, but his latest experiment at ±«Óătv makes it even more clear.
âI used a medical gel to simulate human skin, then created shapes to represent different parts of the body. Using âno-killâ tweezers that squeeze the spider but not hard enough to kill it, I tried to get the spiders to bite. I pinched legs, poked faces, squeezed them from both sides and put pressure on their whole bodies while they were upside down."
âEven in those extreme circumstances, the spiders bit less than 36% of the time, and then only when they were upside-down and squeezed at the same time," he said. Wolf spiders, often seen in homes and generally considered to be non-defensive, were more defensive than the recluses but still didnât bite until they were under intense pressure.
Coticchioâs myth-defying research on recluse spiders follows similar work on brown and black widow spiders. It turns out that brown widows are more defensive when guarding their territory from other widows, and were far more defensive than black widows. The non-native brown widows actively hunt and kill the much-shier black widows in the field and the lab, making them more a hazard to native ecosystems than a danger to human beings.
Going forward, heâs looking at how the Mediterranean recluses â typically hitchhikers from international travelers â are arriving in Florida and then dispersing. âRecluse spiders have very low to no dispersal rates, but the Mediterranean recluse may be different,â he said. âWeâre looking at that in the lab now, but itâs still highly unlikely that breeding populations will ever be established across the state.â
And for Tampa Bay readers who still live in fear of spider bites: 14 of the 20 breeding populations of Mediterranean recluses Coticchio has found live in St. Augustine, with the only breeding recluses found in the Tampa Bay region living in a home where people had recently returned from Europe.
"They were concentrated in the garage near the luggage and no one has been bitten,â he said.
Spiders, particularly recluse spiders, may have a bad rap but itâs extremely unlikely that Floridians will ever be bit by one, he adds.
Original article appeared in .