Someone upthread said compost made the numbers higher, but I don't think so.
I use beneficial nematodes every spring. I only water the apiary enough to keep scattered wildflowers in it alive, pretty much just watering the plant roots, so I do lose my nematodes in summer, but by then they've handled the higher reproductive stage of most critters like fleas and beetles.
If I had a bunch of rotting watermelon in my compost piles it might contribute to shb. but I feed watermelon rind to my mealyworms and hens. And I keep my hives in the sun, shb hate the sun. I also have sbb, some with sticky-boards underneath (and some with boards but no sticky til I get the bees booted off the boards.)