Whilst it may be cold outside, inside the hive the bees will have already started their nests with the Queen laying increasing numbers of eggs each day. A combination of an increasing amount of brood to feed, together with ever decreasing amounts of winter stores, spells danger for the colony. This is when colonies of bees can and often do starve. If in doubt, place a block of bee fondant directly over the feed hole. This is preferred to syrup this early in the year as a couple of pints of freezing syrup inches above the nest can chill the brood (and the bees!).
The bees will of course need moisture to hydrate the fondant, but this is also true of course with their own sealed stores. They seem pretty adept at this, either popping out on milder days to collect water or using the naturally occurring condensation within the hive itself.
As we move into late March/early April (and the weather begins warm up), if the bees are light on stores then a couple of pints of 1:1 sugar syrup will keep them going until spring really gets going.
It's always a nervous time making the first inspection of the year! Pick a mild day with light winds, when the bees are flying. Hopefully you will find that your bees have come through winter, the Queen has started to lay and the bees look healthy and raring to go, with adequate stores.
If your bees have sadly died and the cause is not obvious, then either remove the hive completely in order to sterilise it in case of disease, or at least seal the entrance to prevent robbing by other colonies and thereby transferring disease to other hives.
If the colony is weak and is failing to build up, the two main suspects are normally Nosema and/or Varroa. Plenty of information on both and lots more besides is freely available at www.nationalbeeunit.com.
If you use solid floors, now is a good time to swap it for a clean one. I would delay any marking/clipping of the Queen until the bees are in a position to replace her in case it goes wrong, i.e. wait until there are drones on the wing.
Where I live there is plenty of dandelion in spring, which really gives the bees an early boost (weather permitting), making any new comb a really bright yellow, and if the weather is really mild can provide a decent spring flow.
Let's hope we get a decent summer this year (hope springs eternal etc.) and may all your swarms be low hanging!
Mike Davies Chairman Lampeter and District Beekeepers' Association.