Tuesday, December 4, 2012

Why do African Honeybees Seek Out and Preferentially...

Why do African Honeybees Seek Out and Preferentially

Re-infest Former Honeybee Colony Sites in Structural Cavities?

          Having exterminated African honeybee colonies (hives) since 1993, in residential & commercial structural cavities, we and most all other bee exterminators agree that other African bee colonies often re-infest or inhabit cavities very close in proximity to the initial infestation.  Although we, at AAA Africanized Bee Removal Specialists, Inc., have developed numerous techniques using highly specialized enzymatic products that significantly reduce, if not eliminate this attractive bee pheromone scent inside of the actual colony cavity, we have found that with each passing season, that new colonies are inhabiting other structural cavities very nearby the initial infestation.  If anything can be done to help reduce the probability of re-infestation, determining the main cause and, if possible, correcting the problem could save the homeowner not only the endangerment and expense of another African Bee Colony, but also reduce the chance of other colonies continually re-infesting, building honeycomb inside and consequently damaging the structure.
          At first it was thought that each season’s additional cumulative infestations, and the increasing colony density of African Bee Colonies, were the main reasons re-infestations were increasing.  Then we noted that infestations were increasing in the proximal area surrounding the original bee colony infestation site, even when the entrances were well sealed.
             We began an experiment using actual African honeybees to ascertain the reasons for this phenomenon, and not only did we conclude that new bee colonies were highly attracted to the initial site, therefore supporting the intense pheromone reduction and treatment our company performs while exterminating a bee colony, but we also discovered that bees are highly attracted to the surface of that structure for about 8 feet surrounding the original colony entrance.  This explains why homeowners experience subsequent infestations in their structures nearby the site of original infestation.

 Methods of our experiment
           We constructed small cages from lumber and 1/8" hardware cloth screen.  These “bee cages” were created with a compartment wherein we could insert live bees through openings on the end.  We selected live worker bees from live exposed African bee swarms and inserted approximately 100 bees in a bee cage.  Bees from swarms were selected because they were of prime age to be comprised of mostly scout bees which, are the bees that are sent out to find a new home for their colony.
          We returned to jobs where we had exterminated an African Bee Colony from a structural cavity in a customer’s home.  We randomly selected former sites with a variety of surfaces from various stucco textures, to wood and lumber siding, to unpainted backyard block walls.  All sites selected were older than one year from the date of the extermination, and excluded sites that had already more than one extermination performed.  We positioned a bee filled bee cage directly against the structural surface at varying distances from the original colony’s main entrance and observed the actions and reactions of the caged bees.
          The results were astounding; the closer to the original bee colony entrance, the quicker the caged bees would all turn and move to the side of the cage touching the structural surface.  The reaction diminished at about 7-8 feet from the original entrance.  Also, we observed that the area where the caged bees reacted was often below the original entrance as well as to the side indicating that the original colony’s bees were spraying their pheromone scent on the exterior of the structure adjacent to the colony as they were either approaching the entrance, or exiting the entrance, or both.  The scent would then fall downward with gravity resulting in the bee attraction pattern we observed.  Although it is still unknown if the bees intentionally spray their pheromone scent, it is probable that such scenting is in fact intentional.  We named the exterior area with the pheromone scent the “pheromone target area.”  

          We duplicated the experiment numerous times while at a site of a former extermination.  We also rotated the bee cage device 180̊, which then effectively caused the pheromone scent perceived by the bees to then be on the opposite side of the cage.  As one might expect, the bees quickly adapted and moved to the side touching the surface of the structure.  Numerous additional variations were employed to ensure that the results were accurate.  It was remarkable how the bees could detect and be attracted to the area surrounding a former bee colony site.

 Research results, discussion and conclusion
          It is well known and accepted by bee scientists, that the pheromone scent bees apply to their occupied colony cavities cannot be removed with detergents or vinegar.  Therefore, during a bee colony extermination, our company uses specific enzymes, under pressure, that have been shown to denature and chemically change the pheromone substance on the interior and exterior of the cavity the bee colony has occupied.  However, until the research explained in this article, the surrounding area around the exterior of the colony entrance was not previously thought to require any treatment.

          When our company does a honeycomb removal and we can gain access to the interior of the cavity the colony occupied, we apply a very effective multi-step process using enzymatic agents to clean, denature and deodorize the bulk of the pheromone scent from the interior surfaces of the cavity.  To see how these products might work on the exterior, we applied them to the surface area surrounding about 8 feet in each direction from a colony entrance when we had previously recorded that site was attractive to our cages bees.  The products we have developed have a relatively strong fragrance at first, so we returned after one week to repeat the test.  We were gratified to see that this additional enzymatic pheromone denature work to the exterior surface of the structure had very noticeable results.  Although, the surface of and location on the structure (i.e. if it is a corner) will likely cause some variance to the success, the caged bees were not attracted to the same structural surface area to which they had been attracted to previously, indicating great value in performing this pheromone treatment on an 8 foot area surrounding the original entrance especially when a honeycomb removal is not necessary.

          During a honeycomb cut-out and removal, our pheromone cleaning process involves several steps applying these enzymatic agents and also scrubbing the interior surface of the cavity.  It is important to note that we did not do any scrubbing of any exterior surfaces as this would likely result in causing a change in the sheen or color of the paint on that surface.  As stated above, there was great value in applying two separate enzymatic products mixed to our specifications in a two step process and apply these products to the exterior surfaces within 8-10' of colony entrance in all directions, but especially below the entrance. 

           With this new evidence that bees will indeed spray their pheromone scent on the structural surface several feet outside the colony entrance, as an additional service, our company will offer to apply the various enzymatic pheromone denaturing treatments to the “pheromone target area” surrounding the original bee colony entrance.  Based on the convincing research results stated above, our company believes that this additional service is crucial in helping to prevent future African honeybee infestations that would otherwise occur.

1 comment:

  1. I had never heard about these things before. I hope we will get more new information on African honeybee in future. Really appreciated for your research.