Hands-On Science: Raising Tadpoles

Life science takes on a whole new meaning when you’re raising tadpoles from tiny eggs to hopping frogs.

For young children, the best science curriculum is simple acts of exploration and observation. Be open to new discoveries and seize opportunities to involve yourself in the unfolding of natural processes whether by sitting and watching, spending more time in nature, or being intentional about answering your questions. How does that happen? How does that work? Why? When? What?

A few years ago, my husband seized an opportunity for my boys when he took my youngest son (then 2 years old) to a park, and together they found hundreds of tiny black tadpoles in a pool of water in the shoals of a stream. With a cup from the car, my husband scooped up a few of the tadpoles, and my two-year-old proudly and carefully carried the cup back to the car. Imagine my eldest son’s surprise when he and I returned home, and his brother told us we were going to raise tadpoles. Could we do that without hurting them? I wondered. Raising tadpoles was much easier than I thought it would be. We used an old container box—the kind that can slide under a bed—and put it on the front porch. We filled it with water and some big rocks, and my husband used the water conditioner that we use for our fish aquarium to get the chlorine out. Later, we returned to the stream where we found the tadpoles and collected water from it because there are microorganisms in it that the tadpoles could feed on. (If you raise tadpoles, you might want to start with water from the source where you find your tadpoles, if you don’t already have a habitat set up.)

My husband also purchased a cheap water filter from the pet store, but we didn’t use it to filter the water. Instead, we let it gently circulate the water and make bubbles—this put oxygen in the water. Tadpoles have gills like fish and breath by passing oxygenated water through their gills. However, we have seen tadpoles living quite comfortably in puddles or stagnant water, so a filter may not be necessary.

Next we wondered what to feed our tadpoles. Luckily we found some frog/tadpole food at the pet store, but we also put frozen spinach leaves into the box—the tadpoles loved it! And as I said, we gave them water from the stream so they could eat any microorganisms from it.

When we weren’t keeping vigil over our tadpoles, we kept a piece of old window screen on top of the box to keep out mosquitoes or any predators that might come up on our porch. We felt it was important to keep the tadpoles outside so that they would experience the same temperatures they would have at the stream.

After the habitat was set up, all we needed to do was watch them grow. And they grew fast! As it turned out, our little frogs were fowler toads, which we recognized as soon as they started to get their spots because fowler toads like to live around our house too. Other frogs might have taken much longer to transform into adults, but since I had two little boys watching the whole process, I was grateful for the quick transition. Every morning we would run outside to see our tadpoles, and we could see a difference in them. They got bigger and bigger, they sprouted back legs, front legs, and their coloring changed. Oh the excitement!

During this process, I learned from my herpetologist friend that whenever we find tadpoles around here (in north Georgia) that are solid black, they are definitely toads. Other tadpoles, such as those from tree or chorus frogs, are clear, and if viewed from the bottom, you can see an orange-colored circle, which is their intestines.

We learned on the Savannah River Ecology Laboratory’s (SREL) website that female fowler toads lay eggs in strings with clutches of up to 25,000 eggs in spring or summer after a heavy rain, and that tadpoles go through metamorphosis within two months. But we only had our little tadpoles from June 15 to July 4.

Two out of three of the toadlets lost their tails within a day and were sitting up on the rocks in the habitat. Since they were no longer tadpoles, we no longer knew what to feed them, so on July 4th—a very fitting day—we decided to release them back near the stream where we found them. The third one, which had always developed about one day behind the others, was still in the water and had a tail, so we found a shallow part of the stream to put him in with plenty of leaf cover for him to hide under.

It was a wonderful experience for me, let alone for my children, who delighted in the whole process. I am happy that my husband took that opportunity to do something special with his boys, and I’m glad we gave those three little tadpoles a safe place to grow and reach the next stage of their lives. 

Tadpole Notes:

If you want to raise tadpoles, you should first check your state’s regulations about collecting them from the wild. Some states prohibit this. Furthermore, if you buy tadpoles online, make sure you find a species that can be released into your area (if you plan to release them).

Carolina.com is a reputable resource for schools, and many of their products can be used in the home as well. (This is the company that we purchased butterfly larvae from. You can read about that in the summer 2014 issue of home / school / life.) They will state on their website, if you live in a state where a live specimen cannot be shipped.

This column was originally published in the spring 2015 issue of HSL.

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