[srockey]

I live in Florida, and hear about "Africanized Bees" all the time. We are required by the state to requeen any feral hive we collect to get the African genetics, that may be present, out of the hive.

My quesiton is: Why don't the "African" genetics weaken as they continually mate with the other bees which are not "African"? Is the African gene that dominant? Are the others that recessive? It seem like over time, the Africanized traits would slowly "dilute" to the point where they would not be nearly as evident.

Steve

 

[AR1]

Some of the African genetics offer the bees advantages, so those genes will continue to spread. If we keep killing off the meaner hives we can hope that the genetics for aggression will be weeded out. Apparently that has happened in a few places, like Puerto Rico. I hope that we can keep the increased resistance to varroa.

I hope some Texas beekeepers will chime in. They have been dealing with Africanized bees longer than other parts of the US. Has there been any reduction in aggression since they got here?

 

[pjigar]

I started with a BeeWeaver queen 5 years ago. BeeWeaver queens are open mated and I have heard stories about feisty queens from BeeWeaver. I continued rearing my own queens from the original BeeWeaver queen which are open mated. I went from 1 to 20 colonies in last 5 years. I get a feisty queen in some hives which gets terminated on a regular basis, typically when the hive size is small in early spring. Aggressive hive is totally killed if ever encountered. I had an aggressive queen once in 5 year. And I had feisty queens for about 4 times so far.

Definitions:
Normal: Open a smoked colony after five minutes. Bees buzz around you. They may sting you if given an opportunity i.e. if you have exposed skin. No bee will follow you past 10 feet after you close the hive.
Feisty: Bees jump on veil in dozen or two (mostly guard bees) even after smoking. They are actively trying to sting you on purpose. Bees go back to the hive after you close the hive. Some bees may follow for 20-30 feet after you close the hive.
Aggressive: Cloud of bees jump on you after opening a smoked hive. They are trying to kill you. The cloud of bees will follow you for over 100-200 yards after you close the hive.

 

[Litsinger]

Definitions:
Normal: Open a smoked colony after five minutes. Bees buzz around you. They may sting you if given an opportunity i.e. if you have exposed skin. No bee will follow you past 10 feet after you close the hive.
Feisty: Bees jump on veil in dozen or two (mostly guard bees) even after smoking. They are actively trying to sting you on purpose. Bees go back to the hive after you close the hive. Some bees may follow for 20-30 feet after you close the hive.
Aggressive: Cloud of bees jump on you after opening a smoked hive. They are trying to kill you. The cloud of bees will follow you for over 100-200 yards after you close the hive.

I like your definitions and classification system, pjigar. Good mental images.

 

[snapper1d]

I started with a BeeWeaver queen 5 years ago. BeeWeaver queens are open mated and I have heard stories about feisty queens from BeeWeaver. I continued rearing my own queens from the original BeeWeaver queen which are open mated. I went from 1 to 20 colonies in last 5 years. I get a feisty queen in some hives which gets terminated on a regular basis, typically when the hive size is small in early spring. Aggressive hive is totally killed if ever encountered. I had an aggressive queen once in 5 year. And I had feisty queens for about 4 times so far.

Definitions:
Normal: Open a smoked colony after five minutes. Bees buzz around you. They may sting you if given an opportunity i.e. if you have exposed skin. No bee will follow you past 10 feet after you close the hive.
Feisty: Bees jump on veil in dozen or two (mostly guard bees) even after smoking. They are actively trying to sting you on purpose. Bees go back to the hive after you close the hive. Some bees may follow for 20-30 feet after you close the hive.
Aggressive: Cloud of bees jump on you after opening a smoked hive. They are trying to kill you. The cloud of bees will follow you for over 100-200 yards after you close the hive.

I kill out aggressive hives also.I dont even attempt to requeen because the longer they are alive the more chances those drones will mate with my new queens and I dont want any of those genetics.Close them up and a shot of ether and they are done.

 

[trishbookworm]

Wow. pjigar's Defcon 2 is my Defcon 4. Nice to be where winter weeds out a lot of Africanized genes.... My understanding is that Africanized queens in a swarm can actually enter a European queen's hive and usurp it. Looking at the U of Fl entomology page, http://entnemdept.ufl.edu/creatures/misc/bees/ahb.htm , Africanized bees can swarm much more frequently, also assisting in their out-competing European queens to saturate an area.

I can tell you that frequent swarming in Northeast Ohio is not a lifeway that will succeed. European honey bees can be swarm-prone as well, but that means 2 swarms in a year, not 10.

 

[texbiker]

I caught a swarm in a quarantined county in Texas (like most are). Large swarm that couldn't all fit in the swarm trap. Gentlest hive I have ever worked. Maybe they are gentling down.

 

[AR1]

https://www.biorxiv.org/content/10.1101/2020.03.17.994632v1.full

They studied the spread of africanized bees and what the differences are with Euro bees.
Africanized bees collect more pollen and less nectar, and raise more brood. They also burn energy faster. The authors speculate these might be why they can't spread farther north than they already are. They just starve out in winter.
The africanized bees are 60-70% african in their range and less at the borders. They are about 46% africanized in S. California and decline to basically zero % in N Cali.

 

[Fusion_power]

One of the early observations is that there is a cline for genetics of africanized bees such that percentage declines in higher rainfall and/or colder winter areas. Texas tends to have fairly high percentage genetics in the West declining quite a bit in East Texas. I too got some BeeWeaver queens in 2015 and culled 2 at the end of the season keeping the best and gentlest for breeding.

To answer the original question, In one study, Africanized bees have about a 10 to 1 reproductive advantage over European lines. Also, a single Africanized drone can mate with a European queen and the resulting colony can be too hot to handle. Yes, the genetics get diluted over time, but never to the point of completely removing them from the gene pool and in favorable climates, always dominating European genetics.

 

[AR1]

One of the early observations is that there is a cline for genetics of africanized bees such that percentage declines in higher rainfall and/or colder winter areas. Texas tends to have fairly high percentage genetics in the West declining quite a bit in East Texas. I too got some BeeWeaver queens in 2015 and culled 2 at the end of the season keeping the best and gentlest for breeding.

To answer the original question, In one study, Africanized bees have about a 10 to 1 reproductive advantage over European lines. Also, a single Africanized drone can mate with a European queen and the resulting colony can be too hot to handle. Yes, the genetics get diluted over time, but never to the point of completely removing them from the gene pool and in favorable climates, always dominating European genetics.

In that study I posted above, they note that africanized bees do consistently have 20-30% euro genetics, throughout their range. Apparently they picked up whatever superior genes the euros had while still in Brazil and carried them north and south with them. They are a stable hybrid.

They also note that when varroa came in, African genetics increased in the bordering areas but did not replace the existing euro stocks. There is a band of latitude/climate that the africanized bees cannot extend past, except for some minimal gene flow. Get too much and die in the cold.

To me that looks like good opportunities for selection.

 

[Blue Tick]

I caught a swarm in a quarantined county in Texas (like most are). Large swarm that couldn't all fit in the swarm trap. Gentlest hive I have ever worked. Maybe they are gentling down.

When did you collect this swarm? To my knowledge TAIS ended the quarantine on counties back in 2005.

I travel quite a bit with my job and spend/have spent lots of time in Deep SOTX all along the border. Back in the late 90's and early 2000's the bees we encountered there some of the meanest I've ever seen. As time has gone by, I do believe I've seen the genetics making a change, solely from all the hobbyist and commercial folks. Don't get me wrong, there are some that are still just as mean. I've been beekeeping 33 years, started as a kid and worked several years during jr high/high school for commercial beeks. BeeWeaver queens are good and tend to do well dealing with varroa, but some have been known to be a little pissier than others. I think they are aware of this, but given where we are it's just gonna happen. I've noticed my BW queens that are a little grumpier produce a tad better. Just my observations.

 

[texbiker]

When did you collect this swarm? To my knowledge TAIS ended the quarantine on counties back in 2005.

I travel quite a bit with my job and spend/have spent lots of time in Deep SOTX all along the border. Back in the late 90's and early 2000's the bees we encountered there some of the meanest I've ever seen. As time has gone by, I do believe I've seen the genetics making a change, solely from all the hobbyist and commercial folks. Don't get me wrong, there are some that are still just as mean. I've been beekeeping 33 years, started as a kid and worked several years during jr high/high school for commercial beeks. BeeWeaver queens are good and tend to do well dealing with varroa, but some have been known to be a little pissier than others. I think they are aware of this, but given where we are it's just gonna happen. I've noticed my BW queens that are a little grumpier produce a tad better. Just my observations.

Caught the swarm April 2019 Runnels county. As Far as i know no commercial beekeepers in the area. First thing i noticed is they appear to be smaller than the Italians I had when I lived in New Mexico.

 

[pgayle]

https://www.biorxiv.org/content/10.1101/2020.03.17.994632v1.full

Africanized bees collect more pollen and less nectar, and raise more brood. .

Interesting. I do have a colony that tends to hoard pollen. But they are also very good at making honey. I think they would keep growing until they get too tall for me to add boxes. They are "fesity" but not aggressive at all. In good flow you can stand at the entrance and they don't bother you. You've gotta smoke them to inspect, but they are not near as bad as some I have had. They also use more propolis than any colony I have ever seen. Kind of hard to work because of the propolis, but I rarely need to unless I want to steal a frame for a split.

 

[M.Shelnutt]

So are BeeWeavers part African?

 

[AR1]

So are BeeWeavers part African?

They say on their website that the bees are sometimes hot, and given their location may have some. This is from their website:

...

Our mating grounds are in an area where Africanized bees have been for about 20 years. We feel the African bee incursion did severely affect our stock's temperament for the first 5-10 years, beginning in 1994. In the ensuring years, many of those feral African colonies have been watered down by our bees, existing feral bees and other US beekeeper's stock. Inter-breeding with feral Africanized bees does undoubtedly continue but we take measures to minimize their influence. BeeWeaver floods its mating yards with large numbers of drones and selects breeders that are proven to be calm, workable colonies as well as highly productive, disease resistant and pest tolerant bees. BeeWeaver offers a replacement policy for queens that produce mean bees (stinging without provocation, smoke does not calm them, stinging in high numbers). To be replaced, we must receive notification from you within the first four months after the arrival of the BeeWeaver queen, unless you can prove otherwise that the queen is from BeeWeaver...​

 

[Earthboy]

Hi,

It appears the defensive traits have been diluted over the years (about 20 now) based on the infrequent reports of massive stinging incidents across USA. That said, however, we must not forget that the influx of AHB is not a single, one-time, event at all. Even as I type this response, they are coming up, year in and year out. We had AHB DNA identified in the early 2000, but never had a single incident of sensational massive stinging event, much less leading up to fatality. Another point is there is no such as thing as pure Italian, Caucasian, Carniolan, Russian, Buckfast, etc. any more just as in human population, lots of mixes of different strains. In the spring, I work my bees without a smoker, in shorts and a T-shirt, especially when they are in flow. I love my mongrels: they are hardy as hell.

 

[Earthboy]

Wow. pjigar's Defcon 2 is my Defcon 4. Nice to be where winter weeds out a lot of Africanized genes.... My understanding is that Africanized queens in a swarm can actually enter a European queen's hive and usurp it. Looking at the U of Fl entomology page, Africanized honey bee - Apis mellifera scutellata Lepeletier , Africanized bees can swarm much more frequently, also assisting in their out-competing European queens to saturate an area.

I can tell you that frequent swarming in Northeast Ohio is not a lifeway that will succeed. European honey bees can be swarm-prone as well, but that means 2 swarms in a year, not 10.

That frequency could be an excellent strategy for the bees to fight off mites and other pathogens although undesirable for beekeepers. But in my AHB affected area, I have never seen such swarm spinning colony, though.

 

[Litsinger]

A recent research paper posted on Bee-L provided some interesting insights into the AHB/EHB interaction. Three interesting take-aways:

There does appear to be a fairly stable latitude line wherein ‘A’ genetics are not significantly present- near the 37th Parallel in North America:

Broad surveys show that scutellata -like mtDNA and phenotypes are common in northern Argentina and the southern US, and drop off towards more temperate latitudes, indicating that the rapid spread of these traits has dramatically slowed, if not stopped, on both continents. However, we lack a genome-wide view of the range limits of scutellata ancestry and do not know whether individual high-fitness alleles have already introgressed into higher latitudes.

In North America, we find that honey bees in California have up to 42% A ancestry in the south, tapering down to approximately 0% in Davis, our northernmost sampling site. In comparison, earlier extrapolations based on mitochondrial surveys may have somewhat overestimated genome-wide A ancestry in California (e.g. 65% of foraging bees in San Diego County and 17% in Monterey County carry A mtDNA haplotypes). We also find excess A-like mtDNA diversity in California. While this finding is potentially consistent with scutellata maternal lines being favored during the expansion into Southern California, this pattern is not strongly replicated in South America and even in North America, A mitochondria do not appear to have introgressed far past the northern range limit for nuclear A ancestry.

Below this range, there appears to be a mosaic of genetic combinations that differ in their relative make-up based on fitness to the local environment:

Thus, we conclude that honey bee fitness is more likely to be tracking environmental variables with smooth transitions over broad geographic regions (e.g. climate), which may create intermediate environments where ancestry intermediates have higher fitness, thus broadening the observed hybrid zones. These proposed dynamics are similar to well-studied cases in other systems where bounded hybrid superiority and/or local adaptation to continuous environments maintain adaptive clines across broad geographic regions.

These genetic combinations likely not able to be phenotypically defined as distinctly AHB or EHB:

Our findings add to the genomic evidence that scutellata-European hybrid honey bees cannot be treated as a single genetically and phenotypically cohesive group. We show that bees have intermediate scutellata ancestry proportions over large geographic areas, with no evidence that scutellata-European hybrid honey bees share any defining scutellata ancestry loci (including mtDNA). Colonies within these wide hybrid zones have largely unknown colony-defense behaviors and are likely to show high variance in many traits, overlapping with variation within European bees. These bees defy ‘Africanized’ (vs. ‘non-Africanized’) labels currently used by researchers, beekeepers, and policy makers.

 

[Earthboy]

A recent research paper posted on Bee-L provided some interesting insights into the AHB/EHB interaction. Three interesting take-aways:

There does appear to be a fairly stable latitude line wherein ‘A’ genetics are not significantly present- near the 37th Parallel in North America:

Broad surveys show that scutellata -like mtDNA and phenotypes are common in northern Argentina and the southern US, and drop off towards more temperate latitudes, indicating that the rapid spread of these traits has dramatically slowed, if not stopped, on both continents. However, we lack a genome-wide view of the range limits of scutellata ancestry and do not know whether individual high-fitness alleles have already introgressed into higher latitudes.

In North America, we find that honey bees in California have up to 42% A ancestry in the south, tapering down to approximately 0% in Davis, our northernmost sampling site. In comparison, earlier extrapolations based on mitochondrial surveys may have somewhat overestimated genome-wide A ancestry in California (e.g. 65% of foraging bees in San Diego County and 17% in Monterey County carry A mtDNA haplotypes). We also find excess A-like mtDNA diversity in California. While this finding is potentially consistent with scutellata maternal lines being favored during the expansion into Southern California, this pattern is not strongly replicated in South America and even in North America, A mitochondria do not appear to have introgressed far past the northern range limit for nuclear A ancestry.

Below this range, there appears to be a mosaic of genetic combinations that differ in their relative make-up based on fitness to the local environment:

Thus, we conclude that honey bee fitness is more likely to be tracking environmental variables with smooth transitions over broad geographic regions (e.g. climate), which may create intermediate environments where ancestry intermediates have higher fitness, thus broadening the observed hybrid zones. These proposed dynamics are similar to well-studied cases in other systems where bounded hybrid superiority and/or local adaptation to continuous environments maintain adaptive clines across broad geographic regions.

These genetic combinations likely not able to be phenotypically defined as distinctly AHB or EHB:

Our findings add to the genomic evidence that scutellata-European hybrid honey bees cannot be treated as a single genetically and phenotypically cohesive group. We show that bees have intermediate scutellata ancestry proportions over large geographic areas, with no evidence that scutellata-European hybrid honey bees share any defining scutellata ancestry loci (including mtDNA). Colonies within these wide hybrid zones have largely unknown colony-defense behaviors and are likely to show high variance in many traits, overlapping with variation within European bees. These bees defy ‘Africanized’ (vs. ‘non-Africanized’) labels currently used by researchers, beekeepers, and policy makers.

The article above this thread seems to echo a similar finding, if not almost identical. Good read, though, on both.

 

[Litsinger]

The article above this thread seems to echo a similar finding, if not almost identical. Good read, though, on both.

You are right- the initial paper posted by AR1 was the preprint and now the peer-reviewed version is out.