We had a black snake (Pantherophis obsoletus) catching some rays on a rock ledge. Black snakes are great for keeping mice and venomous snakes at bay, so I like to have them around. But that's not really the topic of today's post...
In the spring and summer, I'm always collecting data from my own hives and tweaking the Mite Calculator variables as needed. But the True Mite Load are not based on my own data, and are "sketchy" as I say on the main page. Today I edited the formula for the True Mite Load after coming across a University of Georgia Bee Lab study that showed an additional 1/3 of a colony's mites were present in the amount of capped brood that would equal about what you'd find in a deep hive body with a strong laying queen. (That's a mouthful.) Previous guesstimates I'd seen indicated this amount of capped brood would have about 1/3 the total mites in the hive. This sounds like semantics on the surface, but consider this: If you have a hive with 40,000 bees and a phoretic mite load of 3% (1200 phoretic mites), then an additional 1/3 (400 mites) would give you a total mite population of 1600 mites, or 4% true mite load. Meanwhile, if you figure the 1200 phoretic mites represents 2/3 of the total mite population, then you've got 1800 mites, or 4.5% true mite load. This difference is further exacerbated when adding the second brood chamber. So for now, I'm basing the True Mite Load calculation off the UofGA study. As I continue to learn and find new information, I'll refine or correct the numbers to reflect my best understanding of reality.