How To Help Bumble Bees With Mites

Bombus pratorum worker with phoretic mites. The mites typically attach themselves to the thorax (upper body) close to the head, or around the junction of the thorax and abdomen.

Above is a photograph of a Bombus pratorum worker, foraging on a geranium flower, whilst  festooned with phoretic mites. 

These mites are pretty common, and they spread between bumble bee colonies by attaching themselves to workers, and then dismounting into flowers visited by the bees.  They then wait for the next bumble bee visitor upon which to hitch another lift. 

They are able to remain in a flower head for up to 24 hours, and it takes just 3 seconds for a mite to hop onto the bee's proboscis (tongue) or legs, and climb up onto the bee's body (Schwarz & Huck 1997).

Although a bumble bee can continue to forage quite happily with a few mites on their bodies, indeed, I have seen bumble bees, so infested that they cannot move!

Note: in biology, the term phoresis, or phoresy, refers to a form of interaction where one species (the phoretic species) is transported by another (the host).

It is this type of infestation that provokes queries - i.e. how to help a bumble bee with mites. 

I cover this subject on my page about what to do if you have found a bee and you wish to help it.  However, I had been meaning to cover the subject in more detail and hadn't got around to it, until I received a brilliant email from a lady called Michaela from the UK, and thus I decided to finally write the page.  Michaela kindly allowed me to share the details of her experience along with her excellent photographs. 

Please note that the water dipping method mentioned below can sometimes work.  If you want to try it, simply encourage the bumble bee onto a spoon or stick, and dip the bumble bee into a small cup of clean water.  The mites will sometimes jump off, or at least be loosened.  Have a couple of cups of water ready, so that you can dunk the bee again, in clean water.  Allow the bee to dry off in the sunshine.

From Michaela:


I have found your page really useful and would like to share my experience last night and this morning. [Michaela had visited my page "What To Do If You Have Found A Bee"]

Yesterday afternoon I noticed a bee in my summerhouse and when I looked closely it was covered in mites. I took it inside as it seemed drowsy and to be dying and came across a website where a lady had dipped the bee in a few small cups of water and the mites jumped off. She then left the bee to dry off.  I tried this but the mites stuck fast. I got a very pointed pair of tweezers and some wooden cuticle removers....holding the bee gently I picked off 17 mites and dropped them into a small cup of washing up liquid and water to drown them.

Phoretic mites removed from a bumble bee - Photograph by Michaela Vardanis

The bee revived, I fed it and fascinated, I watched its long proboscis and red tongue lap syrup.  I put him somewhere warm for the night and this morning noticed three more mites!

Again I picked them off - this time it was a tad more difficult as the bumble bee was a bit buzzy and struggling to get away but I managed to pick or flick these ones off and then put him near the open window and happily watched him fly off into the air!

I have pictures of the mites and the bee feeding if you are interested in posting them on your site.  It is quite easy with care to get the mites off.

Michaela also offered the bee (looks likea Bombus terrestris queen) a little syrup to revive it - here it is, dipping its proboscis (tongue) into syrup to feed - Photograph by Michaela Vardanis

The more difficult ones nestle in around the abdomen, but they do roam on the body and you can flick them off with the wooden cuticle stick.

Hope this helps.

My comment:

I am very grateful to Michaela for these excellent pictures - especially the mites - taken with a 100mm lens!

I have also tried the 'dunking' method, and it didn't work entirely for me, (although  I know it can) and dunking may sometimes help to loosen the mites.

You could also try spraying the mites with plain water to see if this will disturb them.

One thing I would ask though - please only attempt to assist bumble bees that are clearly hampered and motionless. 

If a bee has a few mites but is very active on the flowers, it is better to leave it alone.

Certainly, if you try the dunking method and it doesn't work fully, then you could try the method outlined above.  A blunted wooden cocktail stick or tweezers may do the job if you can be gentle enough not to hurt the bee, whilst sufficiently firm to remove the mites.  If the bee is infested, it will hardly be able to move, so the bee should remain fairly still.

After removing mites, you can offer a little sugar water (use one spoon of sugar to two spoons of water).  To offer the sugar water, you can add a few drops onto the work surface close to the bee, or dip a flower head into the sugar water, and offer it that way. However, if the weather is fine and you have a garden full of flowers, I think it's better to put the bee on a flower so that it can feed itself. 

Here I have a a closer photograph of the same bumble bee pictured top of the page, but if you look very, very closely, you can see the mites are slightly loose.  I have seen them apparently gripping on to bumble bees apparently more tightly than this.

A close up of the same Bombus pratorum worker (Early nesting bumble bee) with phoretic mites slightly loose - they are often clinging more tightly than this.

How to rescue a bee trapped
in a spider web.