I have seen a worrying number of Varroa bodies on the floors of my hives. This is particularly concerning at the start of the season because it suggests much higher numbers of the mites later in the season. If I was a conventional bee keeper I would treat the hives now. I'm not going to. We'll see what happens.
I periodically look at the removable floors in my out apiary in town. I've seen Varroa bodies on the floor of all the 3 hives there. I haven't been able to count the rate of fall yet but there were enough bodies to be a concern. There are also Varroa bodies in my hive in Headington. This afternoon I cleaned the hive floor and, 4 hours later, found 2 new bodies. This rate of floor is alarming.
The hives which contain colonies 8 and 12 were insulated with cork last Autumn. It wasn't the best job ever but it might have raised the temperature of the inside the hive so that more brood were raised. This would provide a great opportunity for Varroa to breed through the winter. I don't have evidence whether the insulation worked. I will try to count mite numbers to see whether there is a clear difference between insulated and uninsulated colonies. Colony 01 is uninsulated and has the very high mite count. Confusing.
Around the start of April there were also piles of dead bees outside the front of my hives in central Oxford. These were not fresh. It wasn't clear whether they died in the hive and were dumped by undertaker bees during the cold weather, or whether they crawled out. Either way it's not good news. Colony 8 had more dead than colonies 4 or 12.
I don't know what these bees died from. There were non-flying bees outside the hive on the ground. They could be suffering from a paralysis virus. There were no obvious signs of Deformed Wing Virus. I just don't know and I'm not likely to find out now.