Spring teased us today. It looked good for a few minutes. The sun was shining and we could imagine that someday it could be Cancun-warm here. But we will get another layer of snow tonight here in western Canada. Nevertheless, people are starting to peak at their bees. A neighbourhood beekeeper sent the lovely photo, above, which he took a few days ago. Mark said his bees are looking good – both hives are alive – and he starting feeding them some pollen substitute. The snow, by the way, provides great insulation and the exposed hive-fronts are facing south.
March is often the worst for wintered bees in our climate. Old over-wintering workers shuffle off to their last snow pile and the weakened hives sometimes suffer greatly from the stress of fluctuating temperatures, low stores, and small clusters. The queen will do her best, but her brood needs warmth and food.
With that in mind, I thought that I’d share the list of common beekeeper excuses for dead hives. These data were gathered from beekeepers by CAPA, the Canadian professional apiculturists’ association. Bees in your area may succumb to other winter maladies, but here’s what Canadian beekeepers self-reported last spring:
Poor queens topped the list as the number one reason for winter losses in most provinces. However, in Alberta, Canada’s main beekeeping province, beekeepers say most hives were lost because of “ineffective varroa control”. Now, that’s a real problem if it means that mites are out-witting the dope we use to kill them.
Weak fall hives was cited as the main culprit in Manitoba and the second leading cause of winter loss in four other provinces. This could be due to mites weakening the hives in autumn or it could be because brood nests plugged out in August, leaving no open areas for the queen to lay. We almost had this problem a decade ago in our own operation. We ran around sticking empty frames into the brood nests in early September. That saved our bees, but many operators were caught off-guard – Alberta had high winter losses that year.
Starvation was the third most common explanation for losses over 2016-2017. This may happen if bees build up too fast in February and beekeepers can’t get into remote snow-filled apiaries. Starvation might also happen in weak colonies that can’t generate enough heat to move their cluster to nearby honey combs. That’s always sad for the beekeeper to discover – ten pounds of honey inches away from a dead mass of starved bees.
Quite a few beekeepers simply said that their bees were killed by “weather”. I’m not sure what that’s supposed to mean. Too cold? Wrap the hives and keep stronger wintering colonies. Too windy? Shelter them. Too long a winter? Well, that’s a killer for all of us and I don’t have an easy answer.
Winter losses for Canada were around 25% last year. That’s an awfully high loss. In the days before mites and cell phones, losses were around 10%. (Cell phones has nothing to with it, but the days before mobiles were good days.) I don’t know if we’ll see 90% success in wintering again – we might eventually subdue mites, but ag-chemicals, pollution, and other bee stresses will likely keep losses high. Beekeeping’s not for the faint-hearted.
Winter’s not over yet. Hopefully, Mark’s bees will begin to build nice populations and they won’t suffer during the next two months of unsteady weather. He’s keeping an eye on them and he’s ready to give them any help they’ll need.