Monday 25 March 2013

The Queen is Dead

This morning I got another email from the National Bee Unit about a starvation risk to bees and advising people to give their colonies a quick inspection to check food stores despite the cold. It's late March now, about time the bees start foraging and their keepers start feeding colonies with sugar syrup to build up numbers after the winter die back. Unfortunately the weather's being a bit random and instead of warmer days we've had snow and ice so the bees can't forage and it's too cold for syrup. I gave all three colonies a block of fondant as winter food back in November. The fondant was still there in January suggesting they were still okay for stored food at the time.

Lifting the lid from the nucleus and removing the polystyrene insulation I could see the upside down plastic food box with fondant in it above the feed hole. I initially thought was probably a good sign, after all if the bees aren't eating the fondant they're probably still eating stored honey. I removed the fondant, had a look in the feed hole but couldn't see any movement, if someone opens a hole in your roof when it's 2 degrees outside chances are you're going to be investigating pretty sharpish so the fact they didn't didn't bode too well. I removed the crownboard completely, I could see bees but they weren't moving.

Dead bees

Looking in the photo you can see all the cells have been opened and are empty, this suggests starvation to me. There is some visible mould but I believe that will have grown after the bees had already died -or at least had died back to too few to control moisture level within the hive.

It's quite a dramatic change from when I opened the hive in January and it was stuffed with live bees and stores. It didn't take long to piece together what had happened. Back in January I'd noticed the cluster was towards the left of the hive. As winter wears on the bees die back the cluster shrinks. As the colony had shrunk they'ed wound up clustering in the seam between the two left most frames. The feed hole is above the seams either side of the central frame. When the bees are clustered they won't break the cluster to look for food so they'ed remained in their cluster and starved to death even though there was a block of fondant big enough to sustain them for weeks about an inch away. There was even some capped honey on the outer face of the leftmost frame which they hadn't opened either.

I gave a handful of dead bees to the chickens, I may give them more another day. As I'm certain the bees died from starvation not disease the comb can be cleaned up by the other hives later and reused when I start up a new colony in the summer. As my colonies are part of the EU Pilot Surveillance Programme I shall have to email the Regional Bee Inspector and let him know the colony died. I removed the insulation, and the sliding bottom board to better ventilate the hive dead hive. I also stuffed up the entrance to keep out wax moth, mice and anything else that might want to set up home in the nucleus, and moved onto Hive1.

Once again I could see the block of fondant sitting in it's transparent box above the crownboard. I removed this and three workers quickly came to see what was happening. This could mean there were only three bees left alive in the whole brood box or it could mean the colony is happily clustered and eating stores. It also meant the bees are able to reach the fondant. When bees are cold they move slowly, you can actually watch stray bees outside the hive grind to a halt as evening falls and temperature drops. The three I saw seemed to be moving about as normal though which suggested to me the colony are okay and still able to maintain heat in the hive. The fondant had only been nibbled a little but I decided to swap it for a fresh block anyway just in case it'd dried out or anything. Instead of removing it from it's foil packaging completely I left it on and cut out a rectangle to expose the icing. Hopefully that'll stop the stuff drying out too quickly. I popped the hive back together and moved onto Hive 2.

That was a different story again. The bees had taken about half a cm of fondant directly above the feed hole and when I removed the block to look below it I could see a large number of bees milling about. This suggests suggests two things: one there's a lot of living bees in there, and two they're low stores hence their actively taking the fondant.

Live bees, Hive2
As with Hive1 I swapped the fondant for a fresh block and closed up the hive. I then got my stethoscope out and had a listen to compare the two hives, they sounded pretty much the same to me so obviously Hive1 does have more considerably more than three bees in it.

Over the past few years winter losses have actually been dropping, although there was an increase in the long wet 2011/2012 winter. Here's the figures from the previous 5 winters, taken from the BBKA's winter loss figures published after the October 2011/March 2012 survey.

Percentage loss of total number of colonies in England overall and North East England
Winter2007/20082008/20092009/20102010/20112011/2012
England30.5%18.7%17.7%13.6%16.2
North East43.0%8.9%16.9%17.1%15.9
Hopefully I'll have no further winter losses.

No comments:

Post a Comment