The winter we had has been a very mild one and, as a consequence, many colonies have come through with more bees than usual. Today I checked most of my hives with the intention of placing a queen excluder and a super above the crown board to provide space should the bees need it. If they become too cramped early in the season they can start swarm preparations quite early. Supers were only added to strong colonies, i.e. those with three quarters or more of adults in the brood box.
However, instead of giving some colonies more space some needed feeding again even though they already had one or two nuc feeder trays. I find it easier to use these small trays to provide a top up rather than bring the contact feeders back into use. Because some colonies have almost a brood box of adults, they are also raising lot more brood than usual and to raise that brood bees need stores.
So do check your colonies, especially the stronger ones as they are the ones prone to starvation. Use a strong syrup to tide them over; the temperature is high enough now for them to take it down.