Deformed Wing Virus

Colony 1 has been continuously occupied for over 6 years. Every spring, except 2018, there have been bees crawling around outside the hive -- stricken with Deformed Wing Virus or some other paralysing virus. These bees became food for Sparrows.

This year seems worse than previous years. There appear to be more bees crawling and for longer. This might not be worse than usual but it feels it. In April it was mostly Drones which were crawling around. Now it is more likely to be workers.

For at least the last 2 years there have been flightless bees crawling around outside Hive A. These bees were clearly suffering from Deformed Wing Virus or another disabling virus. This year there are none.

The cause was explained to me by a researcher at University of Salford. All winter the Varroa mites feed from worker bees. They accumulate DWV virus particles. In spring, when brood production increases they rush in to infest the new brood and transfer more virus to them. These bees show visible signs of DWV -- deformed wings or an inability to fly.

Hive E is having a Varroa mite crisis. I checked today and for the previous 2 weeks. Each time I found hundreds of dead Varroa mites.

High mite drop can be a factor in colony collapse. I don't expect them to perform well next season - if they survive through the winter. I expect them to be weakened, and any brood raised in early spring will be heavily infected with Deformed Wing Virus or other diseases symptomatic of Varroosis.

For at least the last 2 years I have observed a definite pattern in Hive A. In spring there are lots of crawling bees outside the hive. Some are clearly affected by Deformed Wing Virus (DWV); others maybe by another paralysis virus or by exhaustion.

They crawl around near the hive. If you launch them into the air they fall back to earth. They never make it back to the hive and have probably been ejected by the other bees. The Sparrows eat some of them. The others presumably die out of site.

BBKA News ran an article in June about a new project to study Deformed Wing Virus in untreated hives: the ReViVe project*. This is part of Professor S. Martin's research group in University of Salford.

I contacted the PhD student who is undertaking the study and offered my two new hives. These have come from a feral swarm and have not been treated or controlled for Varroa.

The two hives are now part of that study. I have sample tubes to fill with bees for testing. I'm wondering how to persuade the live bees into the tubes. It's going to be tricky.