Lost our hives this winter – trying to figure out what we did wrong?
I'm hoping to get some wisdom from more experienced beekeepers than myself. My husband and I had three hives this year, our first nuc from 2020 that we successfully harvested honey from early in the summer, and two nucs purchased this year (received in May). We're located in North Texas west of DFW.
We lost all three hives. The oldest hive first late in the summer, overrun with wax moths. Then today we opened the other two to find them empty as well, with the beginning of wax moth damage. We've placed all the drawn comb in the freezer to kill the larvae so we can use it later, but we're trying to figure out what went wrong.
I'm curious if giving the bees too much space to defend is sufficient to cause a colony collapse? In the two hives today there was evidence of robbing, several dead bees, but not crazy amounts, and not a large amount of mites on the bottom board (we had treated with Apiguard a couple of months ago, and with the second dose I noted maybe 20-30 dead bees with tongues protruding). Could the Apiguard have been the culprit? During our last check I had noted quite a few hive beetles, so we added extra traps, which had a lot of ants in them today. One of the two hives had been weak so we had been feeding a lot to help them out, and I had given winter patties to both (which were still in the hive with a few bees eating on them). No honey in either hive, some pollen in one, and no brood (maybe a couple of dead capped brood in one hive). I didn't see any dead larvae so I don't suspect foulbrood. A couple of weeks ago when it was nice and warm there was a ton of activity, I thought it suspiciously looked like robbing, and now it appears as though it was.
The hive we lost earlier in the year was too destroyed by wax moths to be able to really figure out what caused the hive to die. We are thinking that we were giving the bees too much space (both nucs had two deep boxes, the old hive had two deeps and two medium honey supers).
We enjoy keeping bees, and I hate the loss of life. I would appreciate any help, tips, or clues to help us next year when we try again!