[IPM Strategies] Tracking the Brown Recluse

Silverfish — a somewhat innocuous yet damaging pest with the potential to wreak havoc on a number of things you might find in an art gallery: vintage books, canvas, you name it — that’s what Tony Stobbe was looking for on a recent job at a local gallery in Fernandina Beach, Fla.

He found silverfish, but also something else entirely: the first documented population of brown recluse spiders (Loxosceles reclusa) in Nassau County, Fla. Small and venomous, the bite of a brown recluse, though considered rare, is dangerous.

“I was able to look at two initial samples,” said Stobbe, a technician with BugOut Service, Jacksonville, Fla. Stobbe said that in late May 2012, he had returned to check up on several glueboards he had placed throughout the gallery, and there they were — spiders. Stobbe had a sneaking suspicion of their identity. “They had six eyes in the perfect arrangement, the perfect amount of hair. I was pretty positive those two were recluse spiders.

“Ever since then it’s been kind of a personal battle, you might call it,” he continued. “Almost a kind of hobby. I would stop by every couple of weeks, to try to track them.”

Since he found those first specimens, Stobbe estimated that he’s found a total of 80 brown recluse spiders inside the small art gallery, both alive and dead. “They were living it up,” Stobbe said. “It was amazing when I started going through all the old files, in the boxes. I can’t believe nobody was harmed over the years with that many spiders.”

An IPM Strategy. Stobbe credited an Integrated Pest Management approach in his successful identification and management of the spider population. He said the location of the infestation posed a challenge.

“The gallery is quite an old building,” he said, noting that the structure has housed a wide variety of different tenants over the years. For instance, a restaurant occupied the space before it became a gallery. “There’s lots of strange construction, which made (the spiders) hard to track. Usually the recluse spiders are transported by freight, movement in and out. The gallery doesn’t have a whole lot of packing coming and going. I’m curious if there is any other activity at any of the other buildings nearby.”

BugOut performed specialized treatments on the building on a handful of occasions to control the population. Stobbe said he used a map of the building to track the spiders’ locations.

Goodbye, Spiders. Since first discovering the infestation last year, Stobbe and BugOut Technical Director Linda Prentice have been able to stop the brown recluses in their tracks. At its worst, Stobbe said he was finding up to six spiders upon each inspection. That number has dwindled.

“I’ve gone through at least 110 insect traps,” Stobbe said. “As crazy as it might sound, I’m going to miss (the spiders) when they’re gone. It’s been like a hobby for me to see how many of them I could collect. It’s a regular account so we’ll be checking it at least once per month through (2013) just to make sure.”

Stobbe said he felt satisfaction in his encounter with the brown recluses. The species has a habit of popping up throughout the state of Florida every so often, though according to the Journal of Medical Entomology, not often enough to warrant Florida being considered a state where the spiders have an established presence.

“I’ve been trying to discover brown recluses since I’ve been doing this, about 12 years,” Stobbe said.

Mission accomplished.

The author is associate editor of PCT magazine. He can be reached at bdelaney@giemedia.com.