Tests for Nosema
To take advantage of the opportunity to test your bees for Nosema,
you will need:
- A labelledpermeable box (eg. match box) for each colony with no fewer than thirty (30) bees in each–giving a moreaccurate result.
The choice of method of collection is yours, but it is suggested you practice beforehand.
Once collected, the bees must be killed; the easiest way is to put them into a freezer for 2-3 hours. Ideally, when tested they should not have been dead much more than 24 hours but samples taken the previous weekend, quickly frozen and kept chilled will be acceptable. If not dead, the microscopists will kill them but how would you know you had enough? Whichever method you use, the bees must be transferred into a permeable container (such as a matchbox) and labelled with the colony number and your name.
How to collect samples for testing:
Nosema is endemic; it may be found in every colony if enough bees are checked. Our check is only that it is not rampant so bringno fewer thanthirty(30) bees from each colony. More is better as more gives a surer result. Bring them in a match box or some other permeable container. Try not to leave them in anything plastic as they rapidly deteriorate.
For a true test, older flying bees are required. Take care not to collect young bees making their initial orientation flights;these are easily recognised by their hovering behaviour in large numbers outside the entrance. When such behaviour is seen, attempts to sample for foragers should be postponed to another hour or day.
Suggestions for collecting them are:
- Choose a good flying day just before the analysis day. Close up the entrance completely with something dark (light colours put them off landing), perhaps a sponge plastic. When hundreds are gathered trying to get in,brush a 30ish load into a large poly bag. Label immediately. Don’t forget to open the entrance before you leave.
- Take a cardboard drinks carton and cut off both ends to make a tube. Put a plastic bag over one end of the carton and rattle the other end against the hive entrance. The bees will come out to see what the fuss is about, fly up the dark tube and into the plastic bag – job done!
- Use a battery driven “Spider Catcher” (as sold by Lakeland Plastics) and release them into a plastic bag; this can be held closed with an elastic band.
- Take a honey or jamjar, remove the lid (keep it separately) and cover the opening with two layers of cling film. Using a pencil or the like, carefully puncture a hole in the centre of the cling film and, by moving the pencil around in the hole; enlarge it slightly without ripping the film. While the bees are foraging, block the hive entrance: towelling material works well, as the bees can’t move around on it very easily. Pick up bees one at a time and push them through the hole into the jar; this can be done with the fingers or use a pair of forceps (tweezers). Or you could wear thin gloves. Generally, the bees can’t escape as they climb up the inside of the jar and cannot get further. When you have thirty bees in the jar, screw on the lid; leave the cling film in place.
- Capture those setting off to forage by covering a restricted hive entrance with the open top face of a deep transparent pot (preferably one with a separate seal-able lid). When there are enough bees inside the pot, slide a sheet of card between hive entrance and pot opening to cover it and remove the pot. Put the pot lid over the card, slide the card away and press the lid closed.
- Prepare your matchboxes, covering a quarter opening with paper stuck lightly into place and punch a hole through with a pencil. Pick them off the flight board one at a time and put them into a matchbox. This opening is covered by a finger or thumb until the latest capture is induced to walk in.
Although authorities such as the COLOSS BEEBOOK and Randy Oliver in Scientific Beekeeping recommend it, it is better not to collect them from a super or from the crown board feed holes. This is because the foragers unload nectar to the young house bees near the hive entrance and it is the young house bees that actually put nectar into the cells in the supers.Since these bees are unlikely to be infected with nosema, there is no point in collecting them for examination.
Also, don’t expect the older bees to be mostly on the outer brood frames; research shows bees of all ages are fairly evenly distributed over every frame.
( Adapted from handout by Jeremy Quinlan )