Bee ecology and pollination in the agricultural landscape - July 2011

On Thursday 7^th July the BEH branch meeting was treated to a very interesting and wide ranging talk on ‘Bee ecology and pollination in the agricultural landscape’ by Dr Juliet Osborne, bee ecologist at Rothamsted Research in Hertfordshire.  She described how harmonic radar and mark-recapture can be used to track honey bees, wild bees and bumble bees revealing much about their behaviour that may then be used in advising agriculturalists how to maximise pollination and maintain diversity. There was general amusement at the images of bees sporting long antennae on their backs and Juliet’s explanation about the patience required to work in this way; when making the observations researchers need to spend all the daylight hours watching hives for specific activity.

Crop pollination in the UK in 2008 had a commercial value of £200 mill. for honey bees and when the wild bees are included £430 mill. Understanding their behaviour and how we may  adapt to it has a significant role in ensuring adequate levels of food production. She explained the three areas of interest (field crops, fruit crops and glasshouse crops) and how the pollination requirements of each vary and are satisfied by different types of bee and hoverfly.

One fascinating example was of Bumble bee colonies imported into large glass houses to ensure pollination of tomato crops. Bumble bees are low level foragers with a relatively short range and if fed with syrup will happily collect the pollen from the tomato plants in the glasshouse and in doing so ensure a suitable level of pollination. They are also able to vibrate their wings very fast which releases more of the pollen from the anthers. The pollination can be very precisely managed and over pollination can be avoided to result in fruits of the high quality demanded by today’s supermarkets. The bumble bee colonies can be easily moved between glasshouses with a minimum of disruption.  Conversely honey bees, who are much higher level foragers with a bigger range, in a similar situation would probably not stay in the glass house but exit through the ventilation in search of different forage; neither can they make the wing vibrations to release the additional pollen. There was much more, interesting detail which illuminated the behaviour in relation to the lifecycle of each bee type and its own nutritional needs.

The  discussion included research into forage types and availability. For example borage forage is not widely available, but there is a field of borage at Rothamsted and the ranges of different bees can be estimated using different dyes and mark-recapture, by siting colonies along a transect way from the field, looking at the pollen types collected in individual hives and the frequency of bees from the different hives in the field.

The talk and subsequent question time carried on for a very satisfying hour and a half to a full audience, the turnout of members and guests was excellent with more than one beekeeper present.