search the Beediverse Blog


Management

Tiny parasitic wasp of mason bees

Margriet,

Can you verify that this picture is a Parasitic Wasp (or not)?

Thanks.
Valeri Wade
Wild Bird Chalet
705 Kentucky Street
Bellingham, WA 98225
360-734-0969
 

 

Hi  Valerie, Thanks for sharing this photo with us and our friends.  Yes this tiny little wasp is a parasitic wasp of mason bees (and other insects).  You can see from the size of the cocoon in the background how tiny this critter really is!  At the moment that this picture was taken, this wasp was listening for bee movement inside the cocoon  ( it hears with its antennae).  Only live bees are parasitized!!  Great picture Valerie.

 

 Frank wrote yesterday:

 Hi Margriet .. am forwarding an email (in mauve below) with images that I recently distributed to all the folks on my “Bee Team” concerning woodpecker damage on Galiano Island.  I think you will find them interesting.  
 
 Do you get many reports of this sort of thing, or do you have such problems with your own nesting boxes?
I hope the summer has gone well for you,
Cheers,   Frank
 
 
 
Subject: Woodpecker damage on Galiano Island
 
Hi Everyone ..  in response to my earlier email about the possibility of woodpecker damage to our nesting boxes, Paul brought two of his boxes to me from Galiano Island, where they had been thoroughly pillaged by woodpeckers.
 
One puzzling thing is that we have flickers and downies in our garden all year round, but never have any of them shown any interest in the nesting boxes.  And the site on Galiano where the damage was done has escaped predation for years. 
 
Anyway, that’s just one more element of mystery surrounding the life of our bees.
 
I’ve attached four images, one overall image of each of the two nesting boxes, and one detail of the worst damage on each one.  It looks as if the woodpecker(s) managed to clean out the front end of every gallery, even those where it(they) did not enlarge the opening i.e. there is not a single gallery left with chambers right up to the front entrance.  As far as I can tell, the first two or perhaps three chambers are gone, particularly in the enlarged openings.
 
Just how much damage has been done won’t be evident until we open them up in November.
 
It’s a jungle out there!
 
Cheers,
 
f.
 
By the way, if you are wondering what the markings are on the fronts of the nesting box trays, there is some evidence that decorating them in some way makes it a little easier for the females to find the galleries they are working on.  It’s not uncommon to see a female come back to the nesting box from a pollen-gathering or mud-gathering trip and enter a gallery, only to pop out immediately and go to a different one. Sometimes it takes more than two tries before she lands where she wants to be”
 
Hi Frank- these are good examples of wood pecker damage :)   and yes I receive these type  of reports nearly every year.
I think you are lucky a pileated woodpecker has not found these nests.  These giants can demolish whole mason bee homes.
 
From the look of the hole- depth, this woodpecker is likely to be the hairy or downy woodpecker.   You mentioned that they have not been predated on before.  this might be because of food availability.  Early in the spring, I have seen damage from bears, where they actually lick out the pollen lumps!  You would not think it would be worth it, but food must have been scarce at the time.
 
One easy way of protecting the nest from wood peckers is the hang them facing inwards- in July when flight has ceased.  Or you can protect them  with a predator guard.   Be aware that the predator guard has to be a good inch away from the face of the nesting tunnel.  Wire screen is NOT too successful.  I think  wire is usually too thin for the bee to see the wire when they come barreling in towards the nest.
 
If my nests are not protected in some way, woody woodpeckers are sure to find them here at home.
 
Oh by the way- I think the nests are still good to use- and the trimmings will assist bees to orient towards their nesting tunnels.  I would sand these rough chipped holes though.
 
 Margriet
 
reply from Frank:

Thanks for the suggestions of turning the boxes around or using predator guards.  Dick S. was very faithful about turning his boxes around each season, I know.  And I’ll pass along your comment about reusing the damaged trays.  You’re quite right that except for the one that was enlarged to the size of a loonie, they just look like someone had taken a countersink bit to them  I think that bird (or those birds) worked awfully hard for what they got!
 
I’ll let you know what we find when we open them up in November.
 
 
 Hello,
 It July 8/12. Is it too early to put a cloth bag over  mason bee boxes to keep out predators?
We are in Comox, Vancouver Island. – Margaret 
Hi Margaret,
Yes it is time, BUT some bees may still be flying! 
I just visited 2 sites today and in both yurt field structures, bees were still flying in and out of their nests. 
Tomorrow, I will go back to these two sites, and remove all the release shelters- to avoid additional parasitic wasps that might still need to emerge.
I will also bring a battery powered bug killer- like a small tennis racket with an electric battery driven electric zapper.  This should get rid of most of the active parasitic wasps.  In another 2 weeks, I will check again, and all, if not most mason bees will have quit by then.  At this time I will place a net bag around each nest to prevent parasitization by the little wasps.
It is quite amazing to see these critters still flying into mid July.-Margriet

 This is my yurt field structure in Bellingham WA.  It is fully laden with highrises and a lot of the tunnel are filled by mason bees.  Today we removed all the release shelters.  Quite a few bees were flying in and out of the nests…more in a subsequent blog.

From Norm Z.
Can you ID these insects for me? If so what are it’s nesting habits? Thanks

Here they are-lovely photos- any body know what species these wasps are?  Probably parasitic types, since they are hanging around the mason bee nests.-Margriet
When I have large numbers of cocoons, I often use trays.  There are about 2000 cocoons on this tray. One tray is turned over to act as a lid.  Trays are offset by 1/4″ so that emerged bees can exit.  Duct tape or strong rubber bands are used to keep trays in position.
Using 1×1 sticks and set between a couple of highrises, a structure is created to hold trays at the upper level of the yurt, but not under the center hole of the roof.



Base tray holds about 2000 cocoons



Two trays are held in place with duct tape.

Two trays offset to create a 1/4″ gap.



Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Popular Posts

Super walls- a closeup

Super walls- a closeup

December 10th, 2013

   When bee finds a nesting tunnel in wood, plastic or some other material, the female bee will plac[...]

Ezy-harvest of tubes- and it is!

Ezy-harvest of tubes- and it is!

January 4th, 2014

Cardboard tubes are used as nesting material for mason bees.  Tubes are one of the many different ty[...]

Parasitic wasp of mason bee cocoons

Parasitic wasp of mason bee cocoons

December 10th, 2013

Margriet, Can you verify that this picture is a Parasitic Wasp (or not)? Thanks. Valeri W[...]

Stop parasitic wasps by using a net bag

Stop parasitic wasps by using a net bag

December 10th, 2013

From summer to early winter place mason bee homes inside a net bag.  This will prevent your mason be[...]

What Mason bees are these?

What Mason bees are these?

December 10th, 2013

Hi,  I put out a box of 7mm tubes next to my normal 8mm  tubes for the Orchard Mason Bees or O[...]