May 15, 2011 – Persistent Spiders
QUESTION:
My employee did an interior and exterior treatment of a home recently, and later the owner's wife and my man found spiders under the bathroom toilet. This was the second time, as the cleaning lady found them there last week. These are small spiders you would normally see outside. What is going on with the spiders? Are they coming up the drains like we have seen some roaches do?
ANSWER:
It's always going to be a "best guess" when trying to analyze a problem without being on site. First, I would really think that spiders would not be coming up through drains, managing somehow to navigate through the water trap in the drain. Of course, I always said that about cockroaches too, and lately have been corrected by some people with first hand observations watching roaches walk directly into the water in a drain and not come back out. But, spiders would just seem even more unlikely to feel comfortable immersing themselves, so I'd be inclined to look for other entry points.
I'm going to assume from your description that the spiders found inside are not web spinners, but are small hunting or wandering spiders. Perhaps they were already inside before the treatment was done and just made their way to the toilet afterward, where they then were spotted by the homeowner. If there is a cleaning person perhaps she washed the floor there after any insecticide application and managed to remove any residual on the floor so that the spiders could wander without fear. Perhaps the spiders are finding a way in somehow behind floor moldings or nearby cabinets. It could even be that they were on the exterior walls or in the attic and found their way down from above, bypassing any treatments around the exterior foundation. I certainly would not decide that the spiders must be immune to our normal insecticides, so either they had not spent enough time on the treated surfaces or they managed to bypass it.
You might place a number of insect glue traps along walls inside this home and see what gets stuck on them and where. Spiders would normally travel along walls, and it may just be that they are coming from other places in the home, and this might lead you to entry points that can be dealt with. If they are small spiders they may be less easily seen on carpets but quickly seen on linoleum or tile flooring as in a bathroom. This time of year we also just have the seasonal explosions of bugs, so there is going to be a lot more pressure on the structure by bugs looking to get inside, so perhaps it was just the odds that a few made it past the outside treatments.
View past Ask Mr. Pest Control questions.
My employee did an interior and exterior treatment of a home recently, and later the owner's wife and my man found spiders under the bathroom toilet. This was the second time, as the cleaning lady found them there last week. These are small spiders you would normally see outside. What is going on with the spiders? Are they coming up the drains like we have seen some roaches do?
ANSWER:
It's always going to be a "best guess" when trying to analyze a problem without being on site. First, I would really think that spiders would not be coming up through drains, managing somehow to navigate through the water trap in the drain. Of course, I always said that about cockroaches too, and lately have been corrected by some people with first hand observations watching roaches walk directly into the water in a drain and not come back out. But, spiders would just seem even more unlikely to feel comfortable immersing themselves, so I'd be inclined to look for other entry points.
I'm going to assume from your description that the spiders found inside are not web spinners, but are small hunting or wandering spiders. Perhaps they were already inside before the treatment was done and just made their way to the toilet afterward, where they then were spotted by the homeowner. If there is a cleaning person perhaps she washed the floor there after any insecticide application and managed to remove any residual on the floor so that the spiders could wander without fear. Perhaps the spiders are finding a way in somehow behind floor moldings or nearby cabinets. It could even be that they were on the exterior walls or in the attic and found their way down from above, bypassing any treatments around the exterior foundation. I certainly would not decide that the spiders must be immune to our normal insecticides, so either they had not spent enough time on the treated surfaces or they managed to bypass it.
You might place a number of insect glue traps along walls inside this home and see what gets stuck on them and where. Spiders would normally travel along walls, and it may just be that they are coming from other places in the home, and this might lead you to entry points that can be dealt with. If they are small spiders they may be less easily seen on carpets but quickly seen on linoleum or tile flooring as in a bathroom. This time of year we also just have the seasonal explosions of bugs, so there is going to be a lot more pressure on the structure by bugs looking to get inside, so perhaps it was just the odds that a few made it past the outside treatments.
View past Ask Mr. Pest Control questions.
