It could be starvation, varroa or pesticides IMHO in that order.
Often what seems like plenty of stores soon disappear once brood rearing gets under way. More bees starve in April than December.
It's possibly a little early for a varroa collapse, although if they where heavily infested & the queen also they can collapse anytime. Usually though varroa problems tend to arise when there are most bees in the colony, May & June. If it was pesticides I'd expect to see a lot of dead bees, inside & outside near the entrance.
||My nerve went and although the topbar had taken no sugar all winter I put some in again about two weeks ago. They had been very busy but there are not that many flowers within easy reach at this time of year. They do not tend to fly towards us and the sea where there are loads of primroses and wild daffodils and quite a few trees flowering.|
Like Tavascarrow says, its spring that can be the killer. Ive lost loads in March.
Now I feed at Christmas and again in mid Feb.
I have a huge colony which Im going to split. Like Joanne says Im never going below 2 colonies again.
They were fed in Oct, bit of candy at Christmas.When we inspected, there was LOTS of food available to them.
There were quite a lot of dead bees on the hive floor.
I wonder if the estate had been spraying, there is lots of corn/wheat planted around the orchard.
I had hoped to get another colony last year, but didn`t.
I`me going to speak to the local chap who does swarm collections,he may get one I could have, funds are low atm, and I can`t afford to buy.
We think we can find a space nearer to home to keep them.That would make life a lot easier.
Sorry to hear you lost your colony. As Joanne says, it is better to have two if you can. It might be worth finding if the local estate has been spraying. They have to take reasonable care not to affect bees, and if they find they were the cause, changing their spraying regime may help them avoid bigger trouble in the future.
It is most probably some other cause. Check the dead bees and check any brood left for obvious disease, but even if you feed bees, they don't always take the food, and sometimes they expand so fast they run out of stores before you are aware.