I'm the only one I know that mentioned how many of my hives were being depopulated by Desert Toads (Bufo alvarius) here in the Picture Rocks area of Tucson, Arizona.
The desert here is an amazing place, on our small acre there is an huge quantity and variety of wildlife. Even right here on my own acre, enclosed on four sides by a six foot high chain-link fence, I've seen Gila Monsters; many other varieties of reptiles; many various lizards and snakes; including several varieties of Geko; several different Horned Toads, which feed on the Harvester Ant colonies that are scattered across our property; a small colony of Blind Worm Snakes (Leptotyphlops humilis) in my front yard, I've seen three of them when I was digging for fishing worms (I raise my own fishing worms); King Snakes, Corn Snakes, Rattle Snakes, various other unidentified snakes. Those are just a few of the reptiles and amphibians, there are also loads of other animals too. Our street is "Camino de Conejo" which means "Street of the Rabbit" and it certainly is that too. Of all these animals, the Desert Toad (Bufo alvarius), is the only one that seems attracted by the presence of my hives, enough so that they travel many miles through the desert just to live on my property and gorge on my bees, day and night - so much for being primarily a nocturnal creature.
When they arrive in the Spring, the first thing they do is to eat any bees that are on the ground, either dead or alive. If they stopped there, that would be fine,even beneficial, but they don't stop there, they never stop. When I go out to the yard, they are there, some even follow me to each hive, perhaps anticipating bees that will be exposed by my activities. I once set a comb on the ground propped up against a hive, a few moments later I felt a toad bump into my foot, looked down and saw three toads sucking bees off of the comb.
Changing to upper entrances to avoid the onslaught of the toads was a blessing in disguise. Since then I've discovered so many more good things about having upper entrances than I could have imagined.