My name is Dr Margriet Dogterom and am the founder and owner of Beediverse. I write this blog for all who love bees and who want to learn more about these wonderful creatures.
This candling video shows the technique of candling. Set up a 6V flashlight in a dark room. Place washed and cleaned cocoons in a petri dish. Rotate petri dish over light to more clearly see what is inside cocoons. Remove parasitized cocoons. Go to shop beediverse on this web site to order petri dishes.
Well not exactly. We are candling mason bee cocoons here. Placed in a petri dish and on top of a flash light, parasitized cocoons become translucent showing the parasitic wasps inside. This cocoon shows at least 4 parasitic wasps. The thing to do? Destroy! More about candling tomorrow. Click on this link to purchase a petridish from Beediverse
Here is something else to do besides cleaning and preparing for spring. A nifty conversion of a 6v flashlight.
to produce lots of bees for the following year, it is important that the majority of parasitic wasps are removed and destroyed. Identification of parasitized cocoons can be done by ‘candling’.
Randy from Olympia has devised a way of optimizing the light from a 6 volt battery for the candling process. I have not done it myself, but having a steady light for candling would optimize the candling process. Candling can identify cocoons filled with parasitic wasps. Once a cocoon with the parasitic wasps inside has been identified these are destroyed. Freezing is a simple way of destroying these tiny wasps when they are inside cocoons. If the wasp numbers are not kept under control- they can parasitize a lot of healthy cocoons. For full details of Randy’s conversion click on the file below. also click on candling in the search window of this blog.
“…I’ve had good luck with it since I made the conversion, getting steady light while my battery waits patiently for a chance to go camping again. The info is in the attached Word document. … if you think it’s of more general interest, you are welcome to put it out there on your website. Let me know if you have any questions, Randy”.
Optimize Your Cocoon
A comment on this blog asked for more pictures on candling cocoons.
Just today I candled 4000 cocoons. It seems like an awful lot, but when they are in petri dishes it is easy to do candle them- about 30 mins or so. I did see some duds that are of some interest. I call anything that is not a fully developed bee a ‘dud’. The percent ‘duds’ in this batch was 2.5%. Anything under 5% is excellent. But even with 107 duds there are some interesting ones. Few had fully developed parasitic wasps- ready to emerge in spring. Others were bee larvae that had not completed development into an adult. In the next day or so I will take some photos and put them on this blog.
I was teaching a group of people about candling the other day. It is a straight forward procedure but the conditions have to be right. The room that you do the candling in has to be completely dark- a bathroom without a window for example. Any extra light besides the flashlight is too much light and you cannot candle the cocoons.
I have had some questions about candling mason bee cocoons. Joe Sadowski from Burnaby, BC thought of this idea- and it works. Candling is just like candling eggs. In a dark room you shine a bright light under the cocoon. With some experience, you can see the adult mason bee in a fetal position inside the cocoon. You can also see empty cocoons or non- viable cocoons, where the larva has died and not developed into a adult bee.
Here is a batch of mason bee cocoons. Mud has been washed off, and mites have been removed. After washing them, cocoons take about an hour or so to dry and then candling can be done.
Place dry cocoons on a petri dish or similar container,over a 6 Volt flashlight. It is easiest to do the candling in a room without windows.
Turn the lights off in the room and look at the cocoons. You will be able to see right through empty cocoons. In normal light, these cocoons look like normal viable cocoons.
You can also see the viable cocoons with the bee inside the cocoon.
Rock, move and rotate petri dish over the light. The light scatters and allows you to see the non- viable cocoons.
All cocoons sold at Beediverse are candled and non-viable cocoons removed.