Over Labor Day weekend, I was exploring the river with a few other St. Croix fans when we paused at a beach. Standing on the sand, I looked down to see a tiny creature swimming around in the shallow water. It was a spiny softshell (Apalone spinifera) turtle hatchling, and we soon saw that there were several hanging out nearby.
Spiny softshells grow up to be one of the largest freshwater turtle species in North America, but these babies were just a couple inches across. They will have a difficult and dangerous childhood, easy pickings for many predators, but those who survive to adulthood can live for decades.
I’ve seen softshell turtles basking on logs before, flattened and drooped over their perch like plastic melted by the sun.
But they have never let me get very close, sliding off almost as soon as I see them. This time, I finally got a good look.
We briefly picked up one of the hatchlings on the beach, and admired its ferocity in the face of invasive giants. It alternated between stretching its neck out to try biting a finger, and pulling its head into the shell as a defense. Spiny softshells are known for being aggressive, and can provide a painful bite — at least, when their mouths are bigger than a finger.
This little one did not give up its attack until it was placed back in the water, where it buried itself in the sand, with only its head sticking out. This behavior is closely connected to their biology and habitat.
Unlike most turtles, spiny softshells are able to breathe underwater. They do this by absorbing oxygen through their skin, greater blood flow, smaller lungs, and other specialized adaptations.
The ability lets the creatures spend long periods of time laying in wait for their food, usually only their head sticking out of the river bottom, buried up to their necks. They’ll nab almost any animal they can manage, from fish to mussels, insects to carrion.
Because of their dependence on underwater breathing, the turtles must live in places where there is enough oxygen in the water. This is especially important during the cold months, when they can spend half the year buried in mud on the river bottom. Moving water like the St. Croix usually provides enough oxygen for them, especially when it’s clean and healthy.
Spiny softshells also need habitat with soft sand or mud on the bottom to bury themselves in. They seek sandy beaches to lay their eggs in shallow holes, laying clutches of up to 30 eggs, and females can be twice the size of males.
These turtles which need the right kind of waters with the right kind of habitat live a precarious existence. Only turtles that survive to eight or 10 years old have the chance to reproduce. The relatively few that survive to adulthood can live up to 50 years. Spiny softshell populations are healthy, but vulnerable to pollution, habitat destruction, and trapping. A web search reveals several websites selling the turtles as pets, usually hatchlings like what we saw.
Our group was happy to simply see the tiny turtles in their native habitat, fierce and fearless, a species that has survived countless generations despite many difficulties.
- Spiny Softshell (Apalone spinifera) – Wisconsin DNR
- Spiny Softshell Turtle – Apalone spinifera – Minnesota DNR
- Spiny Softshell Turtle – National Wildlife Federation
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Mark Hove says
Such a cool turtle!
Sarah Lilja says
Thanks for sharing all these interesting facts about spiny softshell turtles. How lucky were to see hatchlings. We see adults on the river all the time but we’ve never seen a hatchling.
Troy Howard says