Talk by Wally Shaw to a joint meeting of East Devon and West Dorset Beekeepers, 14th January 2020
Where did it all go wrong for honey bees?
Apis mellifera was introduced all over the world in 19th century, including Asia, where it met with Apis cerana and its long-established parasite, Varroa jacobsonii mites. The parasite jumped species and, at some point, became a genetically distinct species, Varroa destructor. This new mite entered the UK in 1992 and the rest is history.
What do we do about it?
Importing bees is not the answer with the attendant risks of importing exotic pests as well (Tropilaelaps, Small Hive beetle etc), plus the very real risk of disease organisms being imported with the bees. The Welsh Beekeepers Association (WBKA) have pledged to minimise imports and make Wales self-sufficient for bees. The WBKA’s pragmatic solution is to enable all beekeepers to make increase/raise queens for themselves. Wally believes this is not as difficult as it is often made to sound.
How queen rearing is taught in Anglesey.
The WBKA publication ‘Simple Methods of Making Increase’, written by Wally and available on the WBKA website, is a good starting point. The simple, small-scale methods are arguably better for the bees and help to retain genetic diversity.
In their first year, ‘Beginners’ are provided with a starter colony, a 5-frame nuc of locally adapted bees. In their second year the ‘Improvers’ are taught to make their second colony for themselves, thereby acquiring a skill for life.
Locally adapted bees have been shown to be better adapted to our highly variable climate, need less management and on average produce higher yields (see COLOSS experiments). Local adaptation will only occur with minimal importation of ‘different’ strains of bee. They will be genetically stable and will be similar in beekeeper’s hives and local feral colonies. Two-way traffic between hives and feral colonies is desirable.
Anglesey bees and Apicentric beekeeping
The characteristics of Wally’s local bees are almost pure Apis mellifera mellifera. They are black without prominent stripes, thrifty with reduced brood rearing in poor conditions, they never exceed their resources and they hoard pollen.
Apicentric means the needs of the bees should be considered first, based on the biology and ecology of honeybees. This is not the same as natural beekeeping.
We need to understand bees
The apparent ‘intelligence’ of bees is a series of hard-wired programmes initiated by various stimulae or prompts, so bees can be conned into doing what we want e.g. with pre-emptive swarm control, but can be confused by, say, an artificial swarm using the Pagden method. Apicentric beekeeping allows the colony to choose the new queen for themselves.
Apicentric guidelines for making nucs
Nucs should be populated with bees from the same colony that raised the queen cells.
Each nuc given 2 or more queen cells on the frames on which they were raised.
Queen cells harvested as soon as possible after sealing (day 8 or 9).
The Nuc entrance should be blocked while being populated.
Completed nucs IMMEDIATELY removed to remote mating apiary.
The reasons why this seems to work are:
It is more NATURAL. The new queens are raised by their own sisters.
Supplying multiple queen cells allows bees to exercise their choice.
Blocking the entrance and moving immediately to another apiary prevents loss of flying bees which ensures good age balance in the nuc.
Using newly sealed cells means there will be a minimum of 9 days to mating. The bees have time to familiarise with their new surroundings.
Selection criteria for breeder colonies
Performance of queen should be known e.g. a queen in her 3rd year.
Only make a small number of new colonies from any one queen. This helps to maintain genetic diversity.
The breeder queen’s colony should be healthy, a good honey cropper, not too prolific, of a reasonable temperament, and not too swarmy.
The second part of Wally’s talk focussed on ways in which bees might acquire Varroa resistance or tolerance.
Over the last 25-30 years breeding strategies have been looking at traits such as grooming, hygienic behaviour, Varroa sensitive hygiene (VSH) and shorter capping periods, with very limited success. When introduced into an open-mating situation the ‘improvements’ are often dissipated.
It has been assumed that natural selection would solve the problem given time, but any Varroa treatment will prevent or seriously slow down natural selection.
There are instances of colonies left untreated in honey production apiaries becoming resistant to mites and able to keep the mite population in check and still produce a good homey crop.
A completely new behavioural mechanism has been found – bees uncap and re-cap brood.
First bees investigate sealed brood cells by examining cappings with tongue and antennae.
Cells perceived to have a problem are uncapped with the mandibles, removing cappings and pupal skin.
Most cells later re-capped.
Some cells may be uncapped more than once.
Other cells may be left uncapped or partially re-capped.
A few cells may have brood removed and discarded (VSH).
It seems this behaviour reduces the number of viable daughter mites that finally emerge, but the uncapping and re-capping does not affect the emerging brood. Mostly, only brood cells in which Varroa has bred are uncapped, which implies bees can detect breeding mites. Whatever the mechanism, uncapping affects the mites but not the pupa and appears to be a result of natural selection.
Uncapping behaviour can be observed in ALL colonies so far investigated, so has probably arisen through natural selection acting on an inbuilt trait which is universal in Apis mellifera.
Wally’s parting remarks were: For natural selection to work, we need to move towards non-treatment!
Strangely, uncapping behaviour does NOT appear to apply to drone brood. More work needed to clarify such issues.