First and Foremost: This is only to satisfy my own personal curiosity. I am not pest certified in this state and referred my client to a good pest outfit. I will not be advising my client directly in regards to these THOUSANDS of big dead beetles. I’m just DYING to know, though. I’ve never seen anything like this!
Here are the details:
The home is 11 months and 2 weeks old. The crawlspace vents are all very well screened (likely trapping the beetles inside the crawl). All of the beetles were dead. Very dead. Dried out. Their dead little bodies were built up in piles, like snowdrifts, throughout the crawlspace. I found no damage to the structure whatsoever. All of the beetles were in the same adult life-stage. The home is in the Pacific Northwest, near Seattle. Images attached.