|The Question: We have a very old hot tub that hasn’t been used for years and the cover has collected a good amount of water from rain and now looks almost like a tiny pond! We recently we have discovered that it is filled with tadpoles! My dad thinks it is a from a tree frog because he has heard them. Should we move them to a nearby water source? Or just leave them alone?
Submitted by: Patrice, Connecticut, USA
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The Short Answer: Patrice, gray tree frog (Hyla versicolor) is probably a good guess because they are known to lay eggs in everything from ponds to puddles. Trent University in Ontario has a nice chart that compares some of the common North American tadpoles. You’ll see that gray tree frog tadpoles have red or orange on the tail. Tadpoles of some other species in the genus Hyla also have red on the tail, but the gray tree frog is the only frog in that genus found in Connecticut. So if you see red or orange on the tail, it’s a good bet your tadpoles are gray tree frog babies.
Unless you think the water will dry up, I would just leave them. They’ll feed on algae and other stuff growing in the water and they’ll prey on small creatures like mosquito larvae. Moving them is risky. One benefit of breeding in puddles and other temporary bodies of water is a lack of fish, turtles and most predatory aquatic insect larvae that eat tadpoles. You might move them somewhere where there are predators that will eat them. Or you might move them to a place where they won’t find the right kind of food. The best bet might be to trust that the gray tree frog(s) chose your hot tub pond for a reason, and hope for the best.
If you really want to help your tadpoles, the best thing would be to make sure the puddle doesn’t dry up. That would be sure death for them. So add water if the puddle gets low, but make sure you’re not adding chlorinated water straight from your tap. That might kill them. You could fill a couple of buckets with water in advance, and let them sit for several days. Any chlorine will evaporate and algae will begin to grow. If you later add the contents of the bucket to the tadpole puddle, it will give them water and food at the same time.
You could also try supplementing their food supply with scrunched up tropical fish food if you happen to have some. But don’t overdo it. If you overfeed, the uneaten food will release ammonia and nitrites, which might kill the tadpoles.
It takes about six to eight weeks for gray tree frog tadpoles to metamorphose into adults. Let us know how it goes. Good luck!