To whom it may concern
Well, It is about time to get involved in some of these discussions
about tracheal mites and bees. I would like to clarify some of the
confusion about Ontario bee stock.
In Ontario we have several bee stocks:
1) Ontario stock: It is a bee stock which is used over the years in
Ontario. The University of Guelph attempted to keep this stock in
isolated area in northern Ontario to main the genetics. This
stock is used as a non-slected control in experiments which were done
by Lin's M.Sc (1992) and Dennis Van Engeldorp's M.Sc. 1994. By the way
Kerry Clark, these bees are not form the mite resistant lines which
have been developed over the last three years by Ontario breeders.
2) Ontario Tracheal Mite Resistant Stock: This stock was known as
NewYork stock. This stock was developed by the University of Guelph in
Western NewYork. The stock was originated from 6 lines of commercial
Ontario stocks and 5 lines of British stocks (Imported by Dr. Roger
Morse, Cornell University). The screening and selection of mite
resistant lines were based on the colony test which was described by
Gary and Page (1989). After three generations, the mite levels in
field colonies were 0-5% without any chemical controls. These lines of
bees were imported to Ontario. They have been kept on isolated
island. Now, three beekeepers are cooperating with the university to
get these lines and use them for production.
3) Ontario Bee Breeders stocks: In 1993, 6 bee breeders became
interested in the Mite Resistant stock-technology. They participated
in the screening test for mite resistance by sending frames of
emerging brood from their selected lines (good honey
producers+winterability) to test for mite resistance. The selected
colonies are used as breeders and drone sources for mating. In this
program, the number of the queen producers increased to 22 (including
David Eyre) and the Ontario Beekeepers Association is supporting this
program. It has been a good program to maintain the mite resistant
lines and to get the commercial beekeepers involved in developing
lines which meet their demands. In the last two years , the number of
queens tested was 700 and the top 25% were selected as mite resistant.
4) Buckfast Bee Stock: The University of Guelph imported Buckfast bee
stocks from England and Denmark. As Kerry Clark mentioned that these
stocks were developed for honey production, aggressiveness,....etc. In
addition, the original bees which were used for breeding were
challenged by mite in early 1900's. The selection continued under the
same condition in England where tracheal mite existed and these bees
were known as tracheal mite resistant!!!!. The first test for
Buckfast bee resistance to mites was conducted and reported by Milne
and Otis, 1991. They showed that the buckfast bees were relatively
resistant to tracheal mites in comparison to North America bee stocks.
These results were confirmed by Lin (1992). This does not mean that
all Buckfast lines are tracheal mite resistant.
I would like to discuss several points about the screening test used
for tracheal mite resistance and breeding for resistance:
1. Our definition to mite resistance bee is that bees have low mite
loads (mite/bee) which will not affect their productivity. Also, we
have to consider the frequancy of genes for resitance in the bee
populations. Good resistance means mor colonies with more subfamilies
within each colony are carrying the resistant genes.
2. It is true that the host-parasite relationship is applied in this
case between the tracheal mite and the honey bee. The tracheal mite
is an obligatory parasite on honey bees. Mites have to survive
but we are trying to find a balance point where mites can survive on
bees without causing economical damages.
3. It is true that we are selecting for bees which have low
attraction for mites during the first 7 days of their live. Lin
(1992) and Nasr, Otis, and Scott-Dupree (1995) found that there is a
significant correlation between the results of the colony screening
test and the average mite levels in colonies which were monitored for
1-year. Thus, we choose this colony test to reduce the cost
of selection and breeding instead of monitoring bee colonies for one
year.
4. We can argue about leaving nature to take its course or using
breeding programs. It is a matter of choice. We believe that breeding
programs are very successful in animal breeding and plant breeding.
Also, they can be successful in bee breeding. Therefore, we got the
beekeepers involved in the program and they can select for what they
want. This breeding program is evolving as a part of their management.
As a result, the progress in developing bee stocks will continue to
increase the frequancy of mite resisnat genes as well as the honey
production in the commercial bee stocks.
5. We encourged beekeepers to select high producing honey, early
spring build up, wintering,....etc. Then, these colonies are
subjected to tracheal mite resistance test.
6. At this time, we have 22 beekeepers are involved in this breeding
program. For sure, not all of them have the same levels of success or
experience. I have one bee breeder who has 70-80% of his tested
colonies are showing low tracheal mite loads in the screening test
for resistance. This guy is enjoying his bees in tracheal mite
infested areas without the need of using chemicals. On the
other hand, we have others who still working on the system.
7. Since 1994, an evaluation field test for mite resistance, honey
production, ..... etc. have been conducted to test Ontario Resistant
(NewYork) stock, Ontario bee breeders' resistant stock, Buckfast
stocks, and non-selected bee stocks in two locations in Ontario. The
preliminary results showed a significant resistance to mite
infestation.
8. Avoiding deceptive marketing, we have been working on this program
for the last few years without any advertising. The expenses are paid
by the government of Ontario to the Ontario beekeepers Association.
Non-of the profit is going to be paid back to the government. All the
intension is to breed bees which is resistant to mites and good honey
producers.
Medhat Nasr
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