Video of Dr. Greg Hunt of Purdue University, Dept. of Entomology speaking to the Southeastern Indiana Beekeepers Association. He talks a little about pesticides, but what really caught my interest is that he's been selectively breeding for bees that will chew the ankles of varroa mites.
His experiences seem to suggest that finding mites with chewed off legs on the bottom board may correspond to hygienic behaviour in honeybees. After selecting for this behaviour, very few of his colonies require mite treatments.
This overview of honey producing flowers is geared towards apiculture in Hungary, but it provides details on some plants beekeepers in North America will be familiar with too.
It provides data on sugar concentration in the nectar from different plants and trees, as well as information in regards to optimal weather conditions and time of day for nectar production.
A few of the highlights for me:
Lindens (refered to as lime in the pdf) do most of their nectar production over night, and thus the bees visit it primarily in the early morning.
Black locust, produces best with highs above 25°C on humid days free of wind and rain, but raspberry can do well on cooler wet days.
There's lots of anecdotal evidence about the benefits of honey on allergies. I could also add my own positive story to that list, but the science looking into the matter still seems rather limited. So far a few studies have said it doesn't help, so it was nice to see some evidence that matches up with my own personal experience.
Of course It still might depend on what you are allergic to, and how likely the pollen of that plant will be found in the honey you eat. This study checked specifically for allergic reactions to birch, and found some very positive results.
The common arguments against honey helping with allergies is that people have allergy problems with wind-borne pollen, and bees tend to collect more of the heavier, sticky non-wind-borne pollen. It's is, however, important to remember that furry bees carry an electrostatic charge, which makes them pollen magnets, so they may very well be collecting some of that wind-borne pollen just by flying through the air.
This paper covers research during which a large number of feral hives were dissected, described and analyzed. There is a whole lot of interesting information here. This information laid the ground work for Seeley's subsequent research on swarm behaviour. Decades later, this is still the source most people refer to for information regarding bees living on their own in tree cavities.
Some items of interest are cavity diameter and volume, comb width, as well as entrance position and size.
A study performed southern tip of Gotland,an island in the Baltic sea where 150 colonies were left unmanaged with varroa mites. After 6 years it appeared that a host-parasite co-adaptation occured with the 5 colonies, plus an addition to 8 swarm colonies that remained.
Original discovery of feral bees co-existing with varroa
A 2007 study by Seeley looking at the honeybee population of the feral bee population of the Arnot Forest showed a stable host - parasite relationship with the varroa mite.
An interesting part of this paper is that it describes how survivor bees co-existing with varroa were taken out of the Arnot forest and inoculated with mites from another apiary. As mite growth in inoculated colonies occurred at a level consistent with control colonies, we might guess less virulent mites have evolved in the unmanaged bee population of the Arnot forest.
Genetic analysis of the Arnot forest survivor bees
In 2015 Alexander S. Mikheyev, Mandy M.Y. Tin, Jatin Arora & Thomas D. Seeley published a study showing that the mite resistant bees living in the Arnot forest are genetically distinct from the bees in the nearby apiaries. They also compared genes of current bees with museum sample of Arnot forest bees from the 1970's. This comparison shows there was likely a genetic bottle neck, and Arnot forest bees have evolved distinct traits as compared to the bees living in the forest prior to varroa. It also suggests that some influx of some amount of new genetics has occurred in the population, including those associated with africanized bees.
There's lots of lists of flowers to plant to help the bees out there, but this is the first time I've seen a scientific comparison of the attractiveness of different plants.
Figure 3 from the paper seems to offer a quick glimpse at which types of flowers were the favourites.
I've been interested in agastache (anise hyssop), since reading praise for it in beekeeping literature a few years ago and because it's native to North America. This gives me a little extra incentive to try planting a little more of it.
I sent Mihail a question and he was quick to remind me that this study was only conducted in one area and results may vary in different regions. So you may want to take this research as inspiration to try setting up a test garden near your own bees and see how your results compare.
