Chimney sweeps will often come across bees that have taken up residence in a chimney and the most common method of removal is to destroy them with an insecticide fumer smoke bomb. If this drastic course of action is taken it is necessary to first sheet up the fireplace opening securely to ensure that it is bee tight before the insecticide is applied. Tip, before sheeting up, lay a plastic sheet in the chamber and fix it in place with gaffa tape to form a sump, then pour onto it a bag of cat litter. A few seconds after the application of the death gas about 30,000 dying and very angry bees will fall down the chimney and the noise behind the sheet is frightening!
The comb in the chimney MUST then be removed. The easiest way is a trip up the ladder with a long handled scraper in the shape of a garden spade and cut the comb from the side of the chimney. This will fall down into the fire place onto the pile of dying bees. Any honey in the broken comb will be soaked up by the cat litter. Wear a bee suit when doing this as many bees that were out foraging will be returning with supplies. Bees are notoriously light fingered when it comes to honey and will rob it from any unprotected source. If the comb is not quickly removed, robber bees will take the honey back to their colonies with the insecticide residue and those colonies will get sick and die. As bees fly up to 3 miles from their hive this contaminated honey can affect all the colonies within 3 miles of the chimney. Please note it is a legal requirement to remove the comb.
When the comb has been removed, cap the chimney with an bee proof cap (C Caps are best) and if necessary fit a chimney pot for it to sit on. Remove the bees, comb and honey sludge and burn it on a bonfire or in a hot wood burning stove. If the chimney is to be used, leave the cap on it until the start of the burn season then remove it, light a fire and keep it burning for the rest of that day.
We have developed two systems of live bee removal, one for a newly arrived swarm that has been in the chimney for less than 3 weeks and another for an established colony.
A fresh swarm will be at the top of the chimney just under the cap. We have developed a bee vacuum that doesn’t damage the bees and after accessing the chimney, it is a simple matter of sucking them up into a bee box and re-homing them elsewhere.
An established colony is encouraged to leave the chimney by fitting a trap out cone to the chimney pot. This is a fine mesh cone fitted to a C Cap with a hole in the top. As the forager bees can’t now exit the chimney through the usual hole, they climb up the cone and fly out of the top. When they return they can’t find their way back in and will cluster on the chimney. A nucleus box (a small hive) containing one frame of brood comb with fresh eggs and nursery bees and other frames of foundation comb is strapped to the chimney so the entrance to the box is close to where the bees were originally going in. The now homeless bees smell the comb and quickly go into the box and start work. They realise that they no longer have a queen and make a new one from a fresh worker egg, which they feed royal jelly. The new queen is ready after about 4 weeks and begins laying eggs. Meanwhile, every day more workers are leaving the chimney and joining their chums in the box. Eventually the old queen, in the absence of enough staff, will leave the chimney with any remaining bees. She will then be killed by the new queen or the workers. The box must be left on the chimney for at least 4 weeks as the developing queen is fragile. When there are no more bees leaving the chimney through the cone, the box and the chimney cap can be removed. The uncapped chimney is then left open for about another 4 weeks to allow robber bees and wasps to clear out all the honey and grubs. This is fine as the comb is not contaminated with insecticide. All that is left after this time is dry empty comb. This can easily be removed by scraper from the top or a wire rotary brush from the bottom. No need to cut holes in the brick work!
It is worth looking at them every week to see what is happening. Earlier this year I noticed there were too many bees to fit in the box so I replaced it with another one containing fresh eggs as before. The bees made another queen and the result was two colonies from the original one. The removed bees must be re-housed more than 3 miles away to prevent them returning.
If you come across bees in a chimney it is worth contacting your local bee keepers and finding one with a head for heights who may be willing to assist.
Bees can live in chimneys for many years and do not cause any structural damage.
I am able to provide more details regarding equipment used should anyone be interested.
NACS Technical Director