Monthly Archives: December 2011

Six inch diameter petri dishes are very handy to have when keeping mason bees, especially when storing cocoons.  Winter storage of cocoons containing live bees can be problematic since you need humidity and air.  Petri dishes allow both air and humidity to pass under the lid and over the lip and into and out of the pretri dish.  Tiny strips keep the lid off the base and thus allowing air to pass.  All this means that living things can be stored in petri dishes.  Another good feature of a petri dish is that organisms can crawl around inside the petri dish, be safe and not escape.
About 100-200 mason bee cocoons can be stored in each petridish.  Petri dish are stackable and can occupy very little space. 
Here are a few ways to use  6″ petridishes:
1.  Store cleaned cocoons inside a refrigerator that is a manual de-frost fridge)
2.  Each petri dish can be labelled according to location and other information.
3.  Store suspect cocoons-I call these DUDS!
When candling, cocoons that do not contain a bee can be set aside and left refrigerated until spring.  In spring, the petri dish is left on the counter.  If any bees emerge they can be released.
4.  Store unknown organisms until emergence
5.  Petri dishes are stackable and occupy very little space.
Stack of petri dishes with cocoons inside a manual defrost fridge.
A thermometer is an important tool to make sure the temperature
is right for keeping cocoons under hibernating conditions. 
In late Jan temperature is lowered to between 2-4C or 35-39F

Always keep a container of water inside the fridge. 
This is an easy way to make sure that humidity is above 60%.

Label each petri dish.

In a manual defrost fridge, there is a freezer compartment
that will require defrosting each year.

In spring, the occasional male will emerge even
though temperatures are low.

For spring emergence, cocoons can be placed into Starter
cottages or Emergence Cottages.  These can be temporarily
stored in the fridge, until weather conditions are reasonable.

Store cocoons inside Petri dishes that may contain parasitic wasps. 
Place on kitchen counter in spring.  If any bees emerge
 they can be released.  Parasitic wasps can be destroyed by freezing .

Here is an update from researcher Mike

“We would very much appreciate if you could place a request on your blog. Coastal B.C. would be convenient, but we are willing to consider anything. We do have a colleague collecting stylopized Polistes in Eastern U.S.A.; that is where we found the large Colletes aggregation I referred to in my last email. Please don’t hesitate to contact us if you think of anything.”

This researcher would like assistance with locating a ground nesting colony of Andrena bees.  (Stylopized bees are parasitized bees).  If you have seen any ground nesting bees, please respond to this web.  Your help is greatly appreciated.  I think he would like the locations to be in the Vancouver region of BC. 

Check out the two links below for beautiful photos of various bee species and stylopized bees.

Hello Dr. Margriet Dogterom,
This year I embarked on an project involving the signalling in Strepsipteran parasites of Polistes wasps. Next spring we would like to expand our research to Andrena bees. Ideally, we need to locate large aggregations to provide a ready supply of stylopized bees. We found one large aggregation that turned out to be Colletes, and another that is not very accessible (It’s on a city boulevard).

Ideally we need to locate colonies before emergence next spring, as the stylopized bees emerge first. Would you happen to know the whereabouts of any Andrena bee aggregations? 
Thank you,
Mike

Photos of stylopized bees

Photos of mason bees and other bees