Relevant link while we are riffing (warning: kid’s music.)
One thing that makes me a bit dubious about some of the answers here is that my pond has big bushes that that just about completely cover the water from above. How likely is it that a bird would go thru all those obstacles to get to the water? Or would it just go elsewhere? I admit I am very ignorant on this subject.
Just to cover all the bases, did Moses ask you to let his people go and you refused?
Clearly it’s spontaneous generation.
Frogs likely use their sense of smell to find water, perhaps by smelling the algae growing in it.
Toads basically live on land and only use water for breeding. Most frogs live closer to permanent water sources. Toads will travel over land for some distance as they follow food and cover more than water. If they stumble across a pond or puddle in breeding season they jump in the puddle and start calling. Toads within a couple hundred yards might show up
Have you considered the possibility that someone (a non-frog) deposited frogs, toads or tadpoles in your puddle?
Human transport explains how many exotic species crossed impenetrable barriers, sometimes well-meaning, sometimes not so much as a joke.
Birds love, love, love bushes near water. Visit a wetland (marsh, swamp, bog, etc.) sometime if you’ve never had a chance, especially during dawn or dusk, and you’ll see hundreds of birds hiding in the plants in and around the wetland. They offer nesting/roosting areas, tall things to scout for prey from, abundance of insects and other food, protection from predators, water, etc.
I’m not really sure how they’re able to identify wetlands from above, but maybe it looks different (glittering sunlight) than you see it from ground level. What does it look like from Google Earth?
What? I don’t understand this. First of all, what would the motivation be? And second, how would they come to know that I even had a pond?
Maybe look over the fence?
People don’t need a (logical) motivation for pranks or just plain mischief. I’ll admit this explanation is a stretch, but it’s not impossible.
Cane toads were imported to Australia by someone who thought it was a good idea. It’s common for exotics to be smuggled into a country by the ignorant, not knowing the damage they could cause, or those wishing to make a buck. Maybe someone thought your pond needed frogs.
Hope you don’t find any alligators, although that would take care of the frogs.
Yes, I know of a very large pond, at least 100 feet in diameter, which fills with water in the winter and is full of frogs in the spring. Then the rain stops for five months, the pond goes dry, and the frogs disappear to reappear in the spring. They didn’t actually go anywhere. They are simply buried in the mud at the bottom of the pond.