The Buckfast hybrid bee was a honey bee developed by "Brother Adam", (born Karl Kehrle in 1898 in Germany), who was in charge of beekeeping at Buckfast Abbey. In the early 20th century bee populations were being decimated by Isle of Wight disease. This condition, later called "acarine" disease, after the acarine parasitic mite that invaded the bees' tracheal tubes and shortened their lives, was killing off thousands of colonies in the British Isles in the early part of the 20th century.
Brother Adam began importing resistant stock from other nations, creating a vigorous, parasite-resistant hybrid honey bee known as the Buckfast bee among beekeepers. This ignited a controversy with some beekeepers, led by Beowulf Cooper, declaring that hybrids were not good for British beekeeping and seeking to find remnants of the British black bee that Brother Adam had declared extinct, from which to breed back to a pure strain, as close as possible to the original bee. Cooper founded an association, now known as the Bee Improvement and Bee Breeders' Association, to improve and propagate the British bee.
The Buckfast bee is popular among beekeepers and is available from bee breeders in several parts of the world. Most of their qualities are very favorable. With the exception of the American variety they are extremely gentle, and some authorities rate them higher than the Italians in most categories. Their main drawbacks are that they have a strong tendency to lock combs together with brace combs, and they are very liberal in their application of propolis to inner surfaces of their hives, thus acting to defeat one of the main purposes of the modern beehive -- that combs should be easily removable for inspection.
While the European variety of Buckfast are considered very gentle, the American variety is far more defensive. There is a debate among beekeepers if this defensiveness is due to breeding for Varroa resistance or partial hybridization with the AHB (Africanized Honey Bee) of the Buckfast line in America. The issues are further clouded in that the two leading American queen breeders are breeding for Varroa resistance and are also located in AHB territory. AHB are usually considered by most experts to be more resistant to Varroa than the European Honey Bee. Note that earlier North American hybrids derived from the originally gentle European black bee stock also had a reputation of being markedly more defensive.