I’m going to guess that mother nature took care of a problem (as usual) and the new bees will be super bees....working twice as fast as the old bees.
Maybe this is why there’s so bloody much clover in my yard this year...
My Dad and brother keep bees and have lost several hives over the last few years. The most resilient hives are the bees that they catch when they swarm from a hive not a kept hive, in other words a wild swarm.
They have noticed a drop in honey production from the hives that have survived the last few year as well. In some cases getting very little honey from their supers.
Hope this recovery continues!