There has been a marked increase of interest in bees which are not being kept by beekeepers, sometimes referred to as feral colonies’ or ‘wild colonies’.
The swarming season which is now upon us is perhaps the best time to think about this subject, as so many beekeepers are contacted by members of the public, with requests to remove bees from attics, chimneys, window-sills, cavity walls, ventillation ducts and other places in buildings where a swarm has decided to set up its home. Frequently there is nothing we can do to help the householder, except to reassure them that bees are not aggressive, and that the colony may even die out over the next two or three years, if it has a heavy infestation of varroa mites. Most of the householders nowadays say that they do not want to harm or kill the bees, and many have heard of varroa; but the length of time a colony may remain in one of these inconvenient spots is by no means an easy matter to determine. Urban beekeeping is increasing, with various States in the US changing their legislation to allow this. The loss of bees as well as other pollinators from agricultural landscape areas, and the increasing importance of urban sites for bees has been emphasised in much recent research.
I was very impressed by a project to survey the ‘feral’ bees which the Scottish BKA has undertaken, reported in the Scottish Beekeeper in February this year. Volunteers make spring and autumn reports, which clearly indicate how well these ‘feral’ colonies fare over the entire year. The Scottish volunteers monitored twenty-nine sites in 2017, but Magnus Peterson, who is running the project, notes that if volunteers fail to report their sites for two years, they have to be deleted from the list. This report actually included twenty-two updated sites. The information gathered is extremely interesting and I would very much like to see a similar project here in Ireland. For example, there is a category for ‘re-colonizing’ specific sites, where a colony may have died out. One site ‘remained untenanted for 4 years’ but was re-colonized this year. As Peterson points out, this demonstrates the continuing attraction of the site and the importance of continuing to monitor sites even when the colony has died out. He gives the figures for the last five years of the survey, showing a re-colonization rate as high as 35% (in 2014), the lowest figure of his set being 10% in 2013 - evidence of quite substantial re-colonization by feral bees. The scent of the old nest, and probably remaining wax, would act as a kind of ‘lure’, I suppose. Peterson notes that sometimes bees flying in and out of sites may in fact be ‘robbers’ rather than a living colony. The deserted sites may even pose a risk to managed colonies in the area, if the robbed colony had serious disease. Optimistically, he also points out that ‘such creatures as wax moths and mice, which are normally regarded as pests by beekeepers, may well be considered as the bees’ (and the beekeepers’) friends’ if they clean up the mess of the abandoned hive. The suspicion that feral bees might constitute a ‘reservoir’ of bee disease is not uncommon, but the evidence I have found seems to point in the opposite direction.
A detailed study carried out in Western Australia in 2006 was specifically tasked with finding out whether the feral colonies acted as reservoirs of AFB [Rob Manning et al, ‘Surveillance of swarms and feral honey bees (Apis mellifera) for the presence of American foulbrood (Paenibacillus larvae sub.sp. larvae) spores and their habitat preferences in Western Australia’]. The researchers found evidence of large numbers of feral colonies:
‘The density of feral honey bee colonies is relatively low in terms of colonies per hectare, but in some areas, particularly in areas of high plant diversity (long/multiple flowering periods), suitable habitat and access to water, feral colonies can occur in high densities. The high-density aggregation of Apis mellifera colonies was reported by Oldroyd et al. (1995) which showed through DNA analysis, that in particular areas, a mix of related and unrelated colonies can exist. In Australia, measurements of feral honey bee colony density are few... (but they) indicate there could be upwards of 1.2 million feral colonies in existence. In any case, there is a very high probability that the number of feral colonies would exceed the number of registered commercial beehives in Western Australia which has varied between 35,000 to 50,000 colonies.’ The researchers found that 3.3% of the 151 feral colonies sampled were infected with AFB and they state that this is ‘similar to other published data.’ They considered that there could be a threat to managed bees in near proximity, mainly from robbing.
In South Eastern Australia, Professor Oldroyd more recently found that ‘disturbed’ areas such as agricultural lands supported fewer feral colonies than 'natural' areas, such as the national forests and parks. He commented, ‘We suggest that colony density may be lower in disturbed than 'natural' areas due to the reduced availability of nest sites and possibly pesticide usage. Because the number of colonies recommended for adequate pollination is 100—1000 colonies/km2, there are insufficient bees to provide optimal crop pollination in the areas we surveyed.’ [Apidology, May 2015]
The underlying question of the relationship between managed and unmanaged colonies of honey bees is addressed in a forthright way by David Heaf on the Natural Beekeeping Trust website. He asks: ‘Are feral bees strictly wild?’ ... Norman Carreck, a distinguished apiologist, Science Director for the International Bee Research Association and editor of the Journal of Apicultural Research, has stated that in his view all bees are wild. Prof. Thomas D. Seeley, who has worked for decades on wild honey bees in tree cavities, writes: ‘l too prefer to refer to colonies living on their own as ‘wild colonies’ rather than ‘feral colonies’ since to my mind honey bees were never really domesticated, so the term ‘feral’ (= having escaped from domestication and become wild) is inappropriate for honey bees.’ The preference for the expression ‘wild’, over ‘feral’, may reflect the influence of the ‘rewilding’ idea of conservation. Just recently several animals have been described as ‘rewilding successes’, including bison in the Netherlands, beavers in the UK and giant tortoises in the Galapagos - but this idea may not fully address the question of unmanaged colonies of bees.
With the coming of the varroa mite in the early 1990s, and the heavy losses this caused, Irish beekeepers generally believed that most, if not all, of the feral or wild colonies in Ireland had probably died out: hence the advice to householders with swarms in inconvenient places, that the bees would probably die out in three years or so. However, Professor Seeley’s research in the Arnot Forest has shown that the surviving colonies evolved to cope with the varroa mites, and indeed have increased the density of their colonies to near the old levels. The fear that varroa would wipe out all wild bees proved incorrect. The immediate comparison which springs to mind would be the devastation of bees in these islands with the advent of Isle of Wight Disease in the early part of last century. This plague too was put down to a mite - the tracheal mite (Acarapis woodi), although this diagnosis was subsequently contested by Bailey and others at Rothampstead. The evidence which was not in question was the sudden, serious increase in colony losses. I would like to remind you of the despairing views which Isle of Wight disease occasioned: ‘This dreaded disease eventually reached Ireland, when in Midsummer 1912, the first infected colony, imported from England, was discovered in a small apiary in Dun Laoghaire. By August 1912 Isle of Wight Disease had appeared ‘ferociously’ at Lurgan, and in 1913 it began to spread to apiaries throughout the country... On 19th September 1917, the Department had made a grant of £30 towards the work of testing the drugs Izal, Bacterol and Hydrogen Dioxide for the control of I.O.W. disease...’ [James K. Watson, Beekeeping in Ireland, 1981]
The thought of applying these chemicals to bees may well shock you. It has been our misfortune to see something which may be comparable to I.O.W. disease, in the U.S. Colony Collapse Disorder, which has also been attributed to a mite - varroa - by many experts. This diagnosis was generally accepted but has more recently been questioned as the cause of the colony losses, and many other factors are now being cited as contributing to the severe, sudden losses. However, the question of whether the feral colonies may be providing a reservoir of varroa mites, which can explode in the form of a ‘varroa bomb’ to infect kept colonies in the vicinity, is still being widely canvassed. In the earlier example, Brother Adam vehemently denied the possibility of the dark ‘Old English’ bees (A. mellifera mellifera) being able to survive I.O.W. disease in the wild, and his programme of breeding from imported strains of bees is credited with restoring beekeeping in Britain and Ireland. However, there have been feral colonies of ‘Old English’ bees discovered since in places like church belfries, which quite simply must have survived, recovered and continued to thrive on their own, like the bees in Arnot Forest. I would like to believe that the very same resilience of these dark bees is true in Ireland, if only we knew enough about our ‘feral’ or ‘wild’ colonies.
The extraordinary ability of A.m.m. bees to continue without any beekeeping by humans is demonstrated by the existence of the Tarraleah bees in Tasmania, Australia. In 1977, H. Ayton published The Black Bees of Tarraleah, which describes the colonies of A.m.m. living deep in the forest in one of the most chilly and damp areas of Australia. These bees were described as ‘pure’ A.m.m. and Ayton believes that they probably escaped from the earliest bee colonies which were brought to Tasmania in 1831. Although Australians usually state that these bees were brought from Britain, it is my personal hope that one day we will be able to prove that they originated in Ireland - after all, the convict ships which carried the stocks departed with horrible frequency from Kinsale. As Professor Oldroyd of Sydney points out, these particular bees would survive much better in the Tarraleah area of Tasmania than any other type, although many other bees were imported over the years, precisely because they are well adapted to the climate of the Tasmanian highlands. He notes that the feral colonies in Tasmanian coastal areas, with less chilly, damp conditions prevailing, have typically A.m. ligustica genotypes, but that this completely changes to A.m.m. in the highland forest areas. He says: ‘We hypothesize that A.m. ligustica and hybrids have lower fitness than A.m.mellifera in cooler regions.’ [Heredity 74, 1995]
Perhaps the word ‘native’ interestingly bridges the gap between ‘wild’ or ‘feral’ bees and the managed bees which we call ‘dark Irish bees’ when we proudly display them in our observation hives at shows, like the recent Bloom in the Park in Dublin, although in other countries A.m.m. goes by other titles, such as ‘German black bees’, ‘Brittany black bees’ or ‘Old English black bees’. In fact, I was patriotically annoyed the other day to find a recent article in a US beekeeping journal (which shall be nameless) stating that these darling dark bees of ours are notoriously ‘bad tempered’ and should be bred out! I would back the A.m.m. bees to survive even such a malicious opinion.
Article by Mary MONTAUT
