Hibernating wasps

by Richard Jones

It's so easy to disturb hibernating insects during winter tidying. The thing to remember is not to rouse them before their time, or they'll surely perish.

Hibernating waspsThe loose bark on old logs is one of the most important hibernating sites for all manner of insects. Here they can remain sheltered from predators, and also from their main enemies during winter: frost and damp. This week they will be sorely tested by the snow.

I regularly find queen wasps curled up, with their wings folded and tucked down underneath their bodies. With metabolism turned down to barely tick-over, they are immobile and can be closely examined (but not picked up) without risk of startling them into defensive action.

Wasps are handsome creatures, and well worthy of respectful study. These ones (pictured, above) were beautifully snug and dry under the bark of a large oak log in Beckenham Place Park.

Parasitoid wasps - ichneumonI recently found this group of related insects (left). They are ichneumons, parasitoid wasps which lay their eggs inside living caterpillars. The hatching grubs then eat the caterpillars alive from the inside. These specimins had chosen a much damper situation under the bark of a pine log.

It's so easy to disturb hibernating insects during winter tidying. The thing to remember is not to rouse them before their time, or they'll surely perish. If they cannot be replaced back in the same place, move them to a similar sheltered, but cool spot elsewhere in the garden. Even raise a new wood stack around them. Anything found indoors, disturbed by the central heating, can be let go into an unheated shed or outhouse where they will settle back down again until temperature and day length switch on the right internal trigger in their body clocks in spring.

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Gardeners' World Web User 05/02/2009 at 17:35

"We never see butterflies in the garden" says my mother, then when cleaning out the log store over Xmas she finds two hibernating peacock butterflies. So they were there, we replaced them as best we could, the covered log pile seems to desirable realestate for invertebrates so we will try to create one exclusively for them.

Gardeners' World Web User 01/10/2009 at 23:34

We have an apparently large wasps nest within a ventilator grille in the outside wall of our bungalow, very near to fruited pear trees. My husband and I are arguing as to whether we get rid of them. I don't want to as they are useful garden predators, but he is afraid they could be causing damage to the under-floorboard area where they seem to be living. They are zooming in and out of the ventilator grille hundreds of times a day. I was stung by one of them on the foot recently whilst cutting back a shrub, with my back to the nest. Obviously in the flight path of one irritated wasp! Any suggestions?

Gardeners' World Web User 16/05/2010 at 11:27

kill them, the only good wasp is a dead one.

Gardeners' World Web User 01/12/2010 at 16:28

Do NOT kill hibernating queen wasps - they will provide the population next year which will control a large number of garden pests. The real enemy of wasps is human ignorance and the more you find out about these wonderful insects, the less likely you are to be interested in killing them.

Gardeners' World Web User 31/01/2011 at 15:40

Found a wasp in garden yesterday and i think it is a queen. Took pity on it and brought it in as thought i was dying and is now living in my back bedroom, it's wings are intact and buzzing but it cannot fly should i leave it there or put it outside again as i think i might have interupted its hibernative stage ?

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