Here is another account and photos, this time from Nikki Simpson. She comments that the fake grass they have under their hives makes it easy to see the dead bees. The top picture is the death toll for one day and the close up shot below shows dead bees with the distinctive dark, shiny bodies as well as young bees.
As a new beekeeper I really wasn’t sure that the volumes of dead bees I found outside the hive in April were normal for the time of year. I was expecting to see the winter bees die and be replaced by new spring bees but the piles we found every day out the front of the hive seemed excessive. Canvassing opinion at the Nosema Clinic in April didn’t shed any light on it, and the death toll continued, consistently losing what seemed like 100s of bees every day. I began to worry if we’d have any bees left, but the colony seemed to be building up as expected so I tried to put the worry to one side but every day my husband would sweep the dead bees into a pile. Strangely, I noticed that while most of the bees looked black and shiny like old bees (with distinctive dark orange stripes at the top of their abdomens), there were also young bees lying on the ground, seemingly unable to walk or fly, but moving feebly. Like yourself, I wondered if it was pesticide poisoning. After reading the newsletter article last month the penny dropped. Everything we observed makes sense in the light of CBPV.
I’ve done some reading since, and there really isn’t much useful information that I could find. There seems to be a distinct lack of research on the topic. I read the Budge et al article in Nature Communications but struggled with the scientific language, so was relieved to find a summary article in the BBKA News, pp.151-154, May 2021. (Recommended reading) There were several points in their research that were interesting to me:
1. CBPV has traditionally been seen as a spring/early summer disease, but their research suggests that more recently it occurs throughout the season, with a slight peak in September. So we may not be out the woods yet! 2. CBPV seems to show clustering by years, most outbreaks are contained within a 40-mile radius, but these clusters do not seem to repeat themselves the following year. So we may catch a lucky break next year and be virus free!
3. Their research substantiates that adult bees are the carriers and found that the faeces of infected bees carry a high viral load (dysentery being a symptom for some bees). Without a known treatment, or any management advice suggested by any sources, other than to remove the floor of the hive so the dead bees can drop out, it’s difficult to know how to help our bees but I wonder if a comb change in the spring is a good idea?
How very unfortunate to have such a devastating disease in year 1, but Nikki and her husband have survived well – here is the concluding sentence of her email:
Our introductory year has been a bit more ‘full on’ than we anticipated but we have loved every minute of it so far!
A comment from Marion
The recommendation from the NBU shown in their video (Chronic Bee Paralysis Virus – Symptoms and Characteristics. – YouTube) that the hive floor be removed from affected colonies to allow dead bees to drop out, as quoted by Nikki above, has cause considerable consternation among some of our members, who have discussed this.
What about robbing? Reducing the hive entrance to a one-bee width is recommended to control robbing, so how would the colonies fare if the whole floor were removed? It doesn’t bear discussion, although several contributors to a beekeeping forum seem to have taken this drastic action. Even if it works at this time of year, there is no way it would in late summer, the worst time for robbing. Maybe these beekeepers haven’t seen robbing at its worst, when there is complete mayhem around the whole hive with the robbers and residents fighting, the robbers winning, then roughly uncapping the stored honey and removing all of it, leaving starving bees to die.
We have been promised contact from our Regional Bee Inspector on this aspect (floor removal) and also on the CBPV problem in general and will report on it. Meanwhile, searches for information and the burning of dead bees continue.