Recent work on pollen quality

Pollen nutrition and colony development in honey bees: part I
IRENE KELLER, PETER FLURI AND ANTON IMDORF
March 2005 | Bee World

> The pollen produced by different plant species may differ considerably with respect to protein and maybe also mineral content. Such qualitative differences might have a strong impact on the foraging decisions of honey bees and could possibly explain preferences for certain pollen types. However, due to our insufficient understanding of the nutritional requirements of honey bees, it may be very difficult to determine which pollen types actually have a high nutritive value for the animals. Most researchers used somewhat arbitrary criteria such as the content of essential amino acids to determine pollen quality.

> No experimental study has so far provided conclusive evidence of preferences for high-quality pollen in honey bees. Indeed, it is possible that honey bees are not able to assess the nutritive value of pollen because they do not consume it directly but transport it to the hive in their pollen baskets. This could also explain why honey bees may readily collect toxic pollen. In conclusion, it is well possible that colonies regulate the quantity rather than the quality of the pollen that is collected. In a natural environment, this may suffice to ensure an adequate supply with all essential nutrients.

Pollen nutrition and colony development in honey bees – Part II
IRENE KELLER, PETER FLURI AND ANTON IMDORF
June 2005 | Bee World

> The consumption of high-quality pollen induces the development of the hypopharyngeal glands in young honey bee workers. As protein-rich secretions from these glands are an important component of larval food, a direct relationship between pollen supply and brood rearing can be expected. Consequently, the availability of pollen is likely to be a central parameter influencing the development of honey bee colonies.

> Several experimental studies have found causal relationships between different pairs of variables associated with pollen supply and colony demography. However, the regulatory mechanisms in honey bee colonies appear to be very complex and a given quantity may be regulated by several others. As a consequence, it may still be impossible to predict the outcome of a given manipulation such as supplementary feeding.

> It also has to be kept in mind that the beekeepers’ interests may differ considerably from those of the bees. Beekeepers will mainly want to maximize the long-term productivity of their colonies. However, producing excessive amounts of honey is probably not an adaptive strategy for honey bees, which are more interested in maximizing their reproductive fitness. Such issues should be considered even in a species such as the honey bee whose behaviour has been influenced through selective breeding.

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm