
Tadpoles - captured momentarily for this photo opp
There’s a ditch near my house that is home to MANY tadpoles. I stop and watch them every day on my walk. Earlier in the season I would have told you that they were probably either wood frog or peeper tadpoles since I saw both of those little spring singers in that ditch, but I’ve long since changed my mind.
Why? I think these little swimmers are too big as tadpoles to grow into those small frogs. Also, they’ve been in the tadpole stage since early May, and they’ve only just begun to sprout the smallest of hind legs in the last few days. Although my National Audubon Society Field Guide to Reptiles & Amphibians doesn’t give me information about tadpoles, I think this is too long for wood frogs and peepers.
I’ve worried about them several times, when the water in that ditch was dwindling, but they’ve lucked out each time with a nice rain.
Most amazing of all is the visual for these spermy-looking critters. I first noticed it on my visit to the ditch in late May. It was also late in the afternoon – on my after-work walk with my dog. Some of the tadpoles were swimming up to the surface of the water — to eat, I assumed — and when they did, their little undersides were luminous! They were glowing orange! To me they looked much as bright and clear as the little orange nightlight I have near my bathroom.

Tadpoles glowing in the ditch
I did an online search for bioluminescent tadpoles, and the only reference I found was for a frog that lives out west somewhere. I did find one reference that said that wood frog tadpoles were iridescent.
So I kept visiting the ditch daily, trying to figure out if what I was seeing was iridescence or luminescence. I couldn’t decide. So one day I captured some in a clear plastic container and drove them a few miles to my friend’s house. It was a dreary, rainy day, and the little guys were understandably more than a little freaked out by their kidnapping and transport. We looked at them for a bit and couldn’t decide, so I drove them back home and put them back in their ditch. (I’m guessing they had some great stories to tell their friends, but that they weren’t believed.)

Tadpoles aglow in the dish
I am truly hoping that someone who reads this post will know about these tadpoles, and can fill me in. Please post a comment and give me information!
by Peg Cherre, Executive Director


This is a good idea. I think I’ll give it a try! (My neighbors already know I’m weird.) I’ll have to do it soon, ‘cuz now that little back legs have started sprouting I think it won’t be long before they’re gone.
Hello Peg! We have never heard of such of thing, but it’s immensely exciting, as we LOVE anything bioluminescent =) Could you take some home and look at them in a dark closet? Or bring a grocery bag and stick the plastic container in there along with your head? People might think you were a little weird (okay, VERY weird), but it should solve the question of whether they are iridescent or luminescent.
Do let us know if you figure out the mystery — this is truly fascinating!