I am currently reading Africanized Honeybees in the Americas by Dewey Caron. It is a very good book abou spread and effects of AHB.
According to this book (published around 2002), AHB have totally taken over from Brazil south to part of Argentina and North to Mexico. In that area, the EHB popluation was totally replaced in a year or two after the AHB arrived. Going south from Brazil, in Argentina, an area developed where there was a mix of AHB and EHB and some hybrids. That also occurred further north at higher elevations. Going further south (which is a more European/less tropical climate), the AHB taper out completely.
Also, it appears that climate affects AHB behavior. Some pure AHBs are less aggressive when kept at higher elevations/colder climates. Apparently, this can be the case with the exact same bees when they are moved from a lowland area to a higher elevation.
Also, I did not realize this, but EHB really were not adapted to S. America. In fact, prior to the spread of AHB, honeybees in tropical South and Central America did not swarm much at all, and they did not live in a feral (escaped) state. As I see it, the AHB spread like wildfire simply because they were much more fit for the habitat/weather in south and central america than the EHB that they replaced. In S. America, EHB were sort of like tulips -- they would live only if planted and cared for by a human. The AHB were like dandelions and could live and spread on their own.
The big debate is where the AHB-EHB line will be in the U.S. (assuming they don't spread all the way to Canada). The Dewey Caron book is several years old, so it does not have current info. This debate is important to me, simply because I live right on the border of where AHB have spread. They have been confirmed just south of Tulsa, OK. Also, based on what happened in S. America, I suspect that the Oklahoma-Kansas area may present the line where the AHB/EHB mix occurs. (Some people predicted that would occur in north Texas, but that did not happen.)
I have been asked to give a talk to our bee club about liability issues relating to bees, and it seems appropriate to work the AHB arrival into this discussion. For my own info and for purposes of that discussion, I'd appreciate some help from people who have first-hand experience of what happened when AHB arrived in an area.
My questions for folks who are having to deal with AHB are:
1. Where do you live in terms that I can understand without a map (e.g. S. Texas/ C. Texas)?
2. When AHB arrived, did they totally take over the area or are they just portion of the "wild" bees?
3. Do you see bees that you think may be an AHB-EHB hybrid?
4. Are all of the AHB in your area aggressive, or are there some that are not much different than EHB?
5. Do you have any practical suggestions for dealing with AHB when they arrive?
6. Once AHB arrive, can a hobbyist safely raise queens (in the absence of a big operation where you can flood the area with drones)?