Ryan McQuoid took these photos of a house invaded by houseflies, thousands upon thousands of houseflies, preparing to overwinter, in the Chinese Camp area, 26 October 2018.
Photos of the adults, showing wing venation, are at the bottom.
It appears the flies were entering by way of one of the two swamp coolers on the roof , and then spreading throughout the house, in “biblical numbers”. This residence was unoccupied, and had been for about two months, and was currently unoccupied. The owner had passed away two months prior. The houseflies are said to have started coming into the house in late September. The house is monitored by a caretaker every few days, and she noticed it suddenly had this huge influx of house flies, notifying us of the problem on 25 October 2018, the day before Ryan took these photos.
Both swamp coolers were dry, so moisture was not an attractant.
Ryan said that when he went on the roof and opened the swamp cooler panels, that hundreds and hundreds of flies poured out, hitting him in the face. Being there were no other points of entry for the flies, Ryan concluded that the swamp coolers were the place of entry. One of the two swamp coolers had hundreds of flies in it as well, but the access to the house had been sealed off with a sheet of foam insulation, apparently placed there by the previous resident.
We see seen housefly aggregations like this, but very rarely. It was a tradition for houseflies, in Columbia, years ago, to overwinter in the top section of a tower at a church. The flies would then come out, around Easter, and we’d get called in to treat and kill them. But I have not seen that in many years. I’d seen similar aggregations of syrphid flies at certain houses in Twain Harte, decades ago. This particular house fly infestation is maybe the worst (or best!) we have seen. The flies were coming in to overwinter. This was not a case of flies breeding inside the structure. The large number of dead flies is due, in my opinion, to the inability of the flies to enter and exit the house, in preparation for a permanent, so-to-speak, overwintering. Many, I think, needed the ability to get back outside, and then re-enter. But the flies could not get back out once they got in.
Ryan helped the caretaker place covers on the swamp coolers, prior to the treatment, to stop further fly entry. Thanks Ryan!!
Jason Mink took photos of this bat house that a resident of Arnold California had mounted on their deck. It actually had bats in it.
The bat house was made by Coveside Conservation Products, in Maine.
22 October 2018.
Chickarees (aka Douglas tree squirrels) took advantage of a rarely occupied home in the Strawberry California (Tuolumne County) area to store their pine cones. The house has a pier foundation, meaning there was no perimeter foundation wall. The chickarees easily burrowed under the siding, gaining entrance to the subarea.
From there, they followed the plumbing, unrestrained, to the where the washing machine’s water exit passed, and had an unblocked entrance to the house.
The chickarees stored pine cones throughout various locations within the multiple story house.
Photos by Jason Mink, 9 October 2018.
Jon Shattuck, one of our service technicians, showed me some photographs he took that day (2 October 2018) of what he suspected of being foamy bark canker. He’d serviced a home in the Monte Grande area, and the homeowner showed him some oak trees, bleeding a foamy sap. I went up and looked. Indeed, this was foamy bark canker, the first case I am aware of in Tuolumne County.
The infected trees were interior live oak, Quercus wislizeni, and the area of attack appeared limited to this one clump of trees. The property owner, Kevin Penfold, said he’d first seen the foamy bleeds about five weeks ago, and they were much worse then.
I searched nearby trees for signs of foamy bark canker, and found nothing. Mr. Penfold uses firewood, but mostly from his own pruning. There is no indication that the beetles and their fungus were transported here. The simplest conclusion is that the oak bark beetles have carried the foamy bark canker fungus with them, via their own dispersal.
Scott Oneto, Farm Advisor for our area, says he saw foamy bark canker in Tuolumne County in 2016, at about the time we had the Angels Oak infestations. But he, like us, had not seen it in 2017 or 2018, until this case. emerged. We must assume that the disease is widespread in our part of the Sierra Nevadas.