OKEHAMPTON Bee-keepers held their last meeting of 2013 earlier this month with around 40 members in attendance.

Clare Densley, head of beekeeping at Buckfast Abbey, gave a talk on research she is doing there into using the small predator mites stratiolaelaps as a method of combating the much larger varroa mite, which is a parasite of honey bees. She discussed the method to use non-chemical means to combat the varroa mites, generating much interest.

The stratiolaelaps mite is a small, non-specific predator. The mite occurs naturally in media such as leaf mould. It has been used for several years in horticulture for the natural control of fungus gnats and thrips and spider mites. It has been introduced into chicken houses to control red spider mite.

Initial trials at Buckfast compared five test hives with five control colonies. About 200 stratiolaelap mites per colony were added to test hives in small pots in a soil substrate. Varroa levels in both test and control hives were reduced at the start of the trial, using chemical intervention, to create a level playing field. Monitoring of varroa drop showed low counts being maintained in the test colonies, against steady rises in the numbers of varroa in the control hives. Control hives required chemical intervention to safeguard the bees. Additional doses of stratiolaelaps were added to test colonies periodically, twice during the year following the initial dose.

The bees in the test colonies thrived well with no side effects from the stratiolaelaps. Clare showed test results with comparison graphs, displaying varroa counts throughout the trial period. The test colonies maintained a consistent low level for most of the trial. Control hives displayed characteristic 'spikes' in varroa levels preceding knock-back by chemical interventions.

The group's next meeting is at 7.30pm on Thursday, January 9 when Simon O'Sullivan, one of the Okehampton branch's committee members, will talk about research into pollination and encouragement of pollinating insects such as honey bees.