I believe this is a juvenile Gulf Coast Toad. I was very surprised to find this little guy in my backyard last summer. As you can see, the toadlet is very small. It is only slightly larger than a toadlet newly transformed from a tadpole. I am not sure how best to estimate the age of toadlets, but I would guess that this one is right around a month old, give or take a week. And, that is what I found puzzling about this observation.
My understanding is that Gulf Coast Toads need a standing body of water to reproduce in. Gulf Coast Toads mate in water, they lay their eggs in water, and they spend almost two months as tadpoles in water. I would expect that even very young toadlets also require close proximity to water, at least for several days after they transform. The problem is there are no standing bodies of water near my house that this little guy could have come from.
The nearest semi-permanent water supply is a small creek that cuts through the middle of our subdivision. At its closest, the creek is several hundred yards/meters away from my house. That means that this little toadlet would have had to traverse the better part of a residential neighborhood, roads and all, in Texas summer heat to make it to my house from the creek.
To further complicate the matter, though, is the fact that my fence has a treated timber baseboard that is actually sunk into the ground. This effectively seals off my backyard from small animals like this toadlet. Still, there are one or two places that it could have made it through, so I cannot totally eliminate it as a possibility.
Is it possible that this is how the toadlet found its way into my backyard? Maybe. Probably. But, is it also possible that Gulf Coast Toads can reproduce in more unexpected places?
Maybe enough water collects for Gulf Coast Toads to breed in unseen places, like under sidewalks, or in water meter recesses. Maybe they are able to make use of standing water in the storm sewage system, and are somehow able to climb out of the deep drains. Or, maybe they are able to breed in areas of vegetation and soil that only stay saturated with water.
There is an area like this in my front yard. Its on the side of my house in a place that sunlight only hits for about an hour every day. Water does not pool here for long, but the ground stays very wet and never fully dries out. The area is a soupy mixture of water, soil, and grass clippings. Is it possible that Gulf Coast eggs could hatch and their tadpoles could live out their larval stage in these kind of conditions? There would be plenty of vegetation for them to eat. Maybe there would be enough moisture there for them to breathe as well. Are there any experts out there who can help address this?
Curiously, I found another toadlet, of similar size, in that exact location in my front yard a little later that day.