Wednesday, August 27, 2014

Honey Bee Hive Population of 4,000 Triggers Rearing of Male Reproductives

(From Entomology Today http://entomologytoday.org/2014/08/21/honey-bee-hive-population-of-4000-triggers-rearing-of-male-reproductives/)

Honey Bee Hive Population of 4,000 Triggers Rearing of Male Reproductives

A western honey bee drone. Photo by Alexander Wild.http://www.alexanderwild.com
When a colony of honey bees grows to about 4,000 members, it triggers an important first stage in its reproductive cycle — the building of a special type of comb used for rearing male reproductives, also known as drones. Drones are male honey bees that develop from unfertilized eggs. Their sole purpose in a colony is to mate with virgin queens from other colonies, thereby spreading the genes of the colony that produced the successful drones.
A team of experts from the Department of Neurobiology and Behavior at Cornell University, led by Michael Smith, studied what starts the reproductive cycle of honey bee colonies. The results are published in the journal Naturwissenschaften.
They found that while every colony built worker comb (non-reproductive comb), not every colony built drone comb (reproductive comb). In fact, only an increase in the number of workers stimulated the workers to start constructing drone comb. This was seen whenever colonies contained 4,000 or more worker bees.
“Colonies with more workers built a greater proportion of drone comb, but colonies with more comb, more brood, or more honey stores, did not do so,” Smith summarizes. “We estimate that a colony needs approximately 4,000 workers to invest in building drone comb.”
The researchers were still left wondering about precisely how an individual worker bee knows how many other workers there are in its colony. Smith and his team speculate that this might have to do with how crowded individuals feel while working side by side in the hive. They are currently engaged in further research to shed more light on this mystery.
The researchers believe that their findings are also relevant to other social systems in which a group’s members must adjust their behavior in relationship to the group’s size.
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Study Finds Honey Bees Originated from Asia, not Africa

(From Entomology Today http://entomologytoday.org/2014/08/25/study-finds-honey-bees-originated-from-asia-not-africa/)

Study Finds Honey Bees Originated from Asia, not Africa

Photo by Alexander Wild. http://www.alexanderwild.com
In a study published in Nature Genetics, researchers from Uppsala University present the first global analysis of genome variation in honey bees. The findings show a surprisingly high level of genetic diversity in honey bees, and indicate that the species most probably originates from Asia, and not from Africa as previously thought.
“The evolutionary tree we constructed from genome sequences does not support an origin in Africa,” said Matthew Webster, one of the authors. “This gives us new insight into how honey bees spread and became adapted to habitats across the world.”
Another unexpected result was that honey bees seem to be derived from an ancient lineage of cavity-nesting bees that arrived from Asia around 300,000 years ago and rapidly spread across Europe and Africa.
Extensive losses of honey bee colonies in recent years are a major cause for concern. Honey bees face threats from disease, climate change, and management practices. To combat these threats, it is important to understand the evolutionary history of honey bees and how they have adapted to different environments across the world.
“We have used state-of-the-art, high-throughput genomics to address these questions, and have identified high levels of genetic diversity in honey bees,” Webster said. “In contrast to other domestic species, management of honey bees seems to have increased levels of genetic variation by mixing bees from different parts of the world. The findings may also indicate that high levels of inbreeding are not a major cause of global colony losses.”
Also hidden in the patterns of genome variation are signals that indicate that climate change has strongly impacted honey bee populations historically.
“Populations in Europe appear to have contracted during ice ages, whereas African populations have expanded at those times, suggesting that environmental conditions there were more favorable,” said Webster.
The researchers also identified specific mutations in genes that are important in adaptation to factors such as climate and pathogens, including those involved in morphology, behavior, and innate immunity.
“The study provides new insights into evolution and genetic adaptation, and establishes a framework for investigating the biological mechanisms behind disease resistance and adaptation to climate — knowledge that could be vital for protecting honey bees in a rapidly changing world,” Webster said.
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Pesticide bill aimed at protecting honey bees awaits Governor Brown's signature

Pesticide bill aimed at protecting honey bees awaits Governor Brown's signature


(from KCBX FM Central Coast Public Radio San Luis Obispo 90.1)
A honey bee lands on an orange blossom in San Luis Obispo County.
Credit Randol White
Santa Barbara County Assemblyman Das Williams (D-Carpinteria) says he hopes Governor Jerry Brown will sign his bill involving the use of a controversial class of pesticides.
Neonicotinoids are the most widely used, and possibly among the most harmful for honey bees according to Williams. His bill, (AB) 1789, has passed the legislature and is now awaiting the governor's signature. It would create a timeline for the Department of Pesticide Regulation to complete its current reevaluation of those compounds.
If signed by the governor, the department would have until mid-2018 to complete its findings, and then two additional years to adopt any necessary control measures.
Agriculture is the number one industry in Santa Barbara County and Williams says he's encouraged by the reaction farmers have to his legislation.
"It's a lot of organic beekeepers and organic farmers that have been supporting this bill," said Williams. "I just also appreciate that the Grange and the farming groups that don't use organics are also neutral on this bill."
Williams says conventional farmers understand that science can help find alternative methods for pest control, while saving the important honey bees in the process.

EPA Approves ASPCRO Guidance on Label Pollinator Language

EPA Approves ASPCRO Guidance on Label Pollinator Language 

(from NPMA's epestworld newsletter of 8-26-14 ePestWorld <npma@multibriefs.com>)
NPMA
The Association of Structural Pest Control Regulatory Officials (ASPCRO) has received a response from EPA to a document submitted in April, seeking guidance for interpreting the new pollinator protection box and use directions on neonicotinoid labels. In EPA’s late July response, the agency confirmed that the ASPCRO guidance letter reflects the appropriate interpretation of the pollinator protective labeling. Click here to view a copy of the EPA response and here to view the original ASPCRO guidance letter.