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  • From: Randall Austin <ra41717 AT gmail.com>
  • To: Blair Christian <blair.christian AT gmail.com>, ocba AT lists.ibiblio.org
  • Subject: Re: [ocba] News report of AHB in Tennessee...
  • Date: Tue, 10 Apr 2012 18:15:26 -0400

The facts of this story do provide a bit of comfort for those who may be worried about African Honey Bees. First my disclaimer: I'm not an expert by any means but I have studied AHBs a bit, have read many good books about them, and have worked with them while doing development work in the Dominican Republic.

First, random AHB finds have occurred many times over the years, including way up north. A single find doesn't really mean anything, although it is interesting.

Second, this find was by a beekeeper in a managed hive, not "loose". Despite what you would logically think, buying packages from AHB-infested areas is NOT the way that AHB spread. One reason for this is that even if you buy free-mated queens from an AHB-infested area, it is likely the production queen which produced the off-the-rack queen in your package was a "known quantity" (European), not AHB. If so, the AHB genes come in through the drones that mated with her, not the queen. The subsequent workers are hybrids, and hybrid AHB are inferior to either pure AHB or pure European (they have features which create competitive disadvantage). The spread of AHB from Brazil has been marked by "hybridization zones" at the leading edge of the incursion, but those are back-filled by some-what pure AHB (queens and drones). True embedding has occurred when the maternal genes are AHB, not just the paternal genes. So a few hot hives in a beekeeper's yard, when the source is known, don't necessarily signify anything of importance.

Third, there have been AHB in Arkansas and Florida for several years, but this find was between Knoxville and Chattanooga. It is impossible for me to believe that they got there, previously unobserved, via migration from Arkansas or north Florida, and as I mentioned it is migration that is the problem, not scattered finds.

Fourth, the article talks about the bees being "17% Africanized". I assume this means that 17 percent of the sample of bees showed AHB traits. So that supports the assumption that the queen was European and she just got mixed up with a bad crowd.

Fifth, David Tarpy at NCSU is a genuine expert --- he has published on the topic. He has posted a fact sheets about AHB on the NCSU apiculture department website. So if AHB ever gets here, we have excellent support.

If you want to read a great book on the topic, try Dewey Caron's "Africanized Bees in the Americas". He'll calm any hysteria you may have while also explaining how AHB are NOT "just like our bees but meaner." They have many, many traits in addition to aggression that are totally undesirable for Piedmont NC beekeeping.

Randall Austin


On 4/10/2012 5:11 PM, Blair Christian wrote:
To clarify what I was getting at, it looks like there may be one to
four genes related to tendency to sting. But I still don't know what
the "definition" of "Africanized" means....
http://www.genetics.org/content/148/3/1203.short

FYI: A "QTL" is basically the location of a gene which can have more
than type. They interbred EHB and AFB many times, examined each of
the colonies for tendency to sting, then looked at the type of each
gene for the thousands of genes and tested whether there was a
relationship between a gene (loci) and a trait (tendency to sting).
The LOD is a statistical measure related to p-values or false
positives... Here are papers that cite that one above
http://scholar.google.com/scholar?cites=4247904885524219267&as_sdt=5,34&sciodt=0,34&hl=en

I don't know if that research has been reproduced, but it looks like it was...

Here's an attempt to repeat that research
http://www.springerlink.com/content/6r5hqmrdht3rxvk1/

It looks like there is a relationship between a gene they named
"sting1" and defensive/guarding behavior.. I didn't have time to
fully parse it.

Here's another one looking at population genetics of Africanized/not bees:
http://www.culturaapicola.com.ar/apuntes/revistaselectronicas/Oldroyd/22.pdf
The gist seems to be that there are different gene variants floating
around in Africa. Do all of them display "Africanized" behavior of
stinging?

Here's an interesting article about guarding:
http://www.sciencedirect.com/science/article/pii/S0003347287801720

So more specifically, my question is: Suppose you are a state
inspector. What "definition" do you use before making a press release
saying you have AHB? Do you find a hive that displays "aggressive"
behavior, then test? Or do you test randomly? FYI: I called the
Tennessee state apiary inspector Mike Studor to see what criteria he
was using...

The thing I don't like is using scientific names with abandon- in
reality, there are usually genes underlying these behaviors, so it's
much better to talk about "bees with version XYZ of the sting-1 gene"
being in an area, or saying that the percentage of colonies with at
least one copy of the XYZ variant of gene sting-1 is above some
value....

Some of this is discussed in:
http://en.wikipedia.org/wiki/Africanized_bee#Morphology_and_genetics


So what is the upshot? My guess is that genes from Africanized bees
will become more common over the years and we probably won't notice
any big changes- there could be more swarming, smaller colony/swarm
sizes, more absconding, more stinging- but only a little every year...
My guess is that as we order more packages from Georgia or farther
south where some Africanized bee drones are intermingling with virgin
bees going into package bees, we'll see this behavior, but we'll
consider it "normal" because it won't change much from year to year.
We'll consider it normal unless we were to say, do some beekeeping
overseas or farther north..

I studied some genetics, and I rambled a bit, but if anybody has any
questions or clarifications, let me know and I can try to answer
them...

Best,
Blair

On Tue, Apr 10, 2012 at 3:56 PM, Blair Christian
<blair.christian AT gmail.com> wrote:
So it looks like there are AHB (Africanized Honey Bees) in TN. Are
they really all around and we just don't notice because we're not
looking for them? Are they so hybridized now that they aren't as
aggressive? Does anybody know how you officially classify a bee as
AHB? Is it through genes, phenotype or both?

http://www.businessweek.com/ap/2012-04/D9U24OP80.htm
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