Unfortunately and sadly, those numbers don't sound far off the mark in my opinion. Similar losses I believe are mounting in Tennessee. Early Spring is the most dangerous time of the year for our beehives due to a number of factors but these factors are heavily compounded if the hives make it into Spring in very weak and unhealthy condition.
In my opinion mites, that are continuously being incorrectly treated for late Fall & Winter survial by insisting upon using varroa mite treatments that treat and are effective on phoretic mites only as opposed to employing treatments that kill the reproductive/foundress varroa mites.
Other factors that are causing these Winter losses and weakenings such as tracheal mites. Most beekeepers do not treat for tracheal mites. They are very difficult to detect visually until K-wing virus starts effecting the bees.
Another big factor is beekeepers are NOT checking their hives on a frequent enough basis to ensure the hives have adequate food resources that are in contact with the cluster.
Although I am sure many will argue the point of whether or not hive insulation is necessary, it has been my experience that properly insulated hives have a much higher survival rate than those that are not insulated. Beehives in which the internal temperatures are stabilized from dipping below approximately 35 - 40 degrees F, the bees will still cluster up but are able to move around inside the hive to access food resources inside the hive that may not be in contact with the cluster. Once the internal hive temperature drops much below approximately 35 - 40 degrees F, the bees typically will NOT break out of the cluster. If food resources are not in contact with the cluster, the bees will starve and then freeze to death in many cases.
Lastly, many beekeepers insist upon carrying their beehive into the Winter in double and triple deep brood box configuration. This is far too much space for the cluster to occupy and keep at a suitable temperature. Even if the cluster is large enough to do this, they typically consume large amounts of food resources to do this and if not closely monitored to remove empty brood boxes as food resources are consumed and adding food resources as needed, will again run up against the issue of starvation and freezing to death.
In early Spring as hives begin to brood up, leaving the hive insulation on until any danger of sudden freezes can help to significantly reduce hive losses due to sudden late hard freezes like we had last April in the 3rd week. Once the hive has a significant amount of brood present, the bees will NOT cluster up in the event of a sudden hard freeze and will sacrifice themselves to protect the brood typically ending with the entire hive lost over night. Even the largest and strongest hives are susceptible to this. Ask how I know???
As to the issue of the Flow Hive. In my opinion, they sound good and the video's look good but then I think about how well these Flow Hives will hold up over several seasons with the bee propolizing them and the bugs that may get into them while in storage over the Winter, not to mention the prohibitively high cost. I think I'll stick with the conventional honey super.
Anyway........that's my humble 2 cents worth on this.
