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Why do catfish swim in the deep?

Sam, age 5

Catfish are bottom feeders. they hang out where the food is. They use their sensitive barbels, which look like cat whiskers, to find insects, fish, mussels and crayfish in the depths of the water. Channel catfish and black bullheads also eat decaying and dead matter that lie on the bottom.

Staying near the bottom of a stream may also help catfish conserve energy. Water on the bottom of streams moves slower than the water above.

What do turtles do in the winter when all the ponds are frozen?

Courtney, age 12

Many turtles that live in the water lie on the bottom or dig into the mud at the bottom of a pond or river in the winter. They don’t need as much oxygen because their heart rates slow down when the temperature of the water goes down. Cold water has more oxygen than warm water. Blood vessels near the surface of the turtles’ skin allow them to absorb oxygen from the water. When the water warms up, turtles will surface more often to get enough oxygen to breathe.

Some aquatic turtles and most land turtles dig shallow holes in soil and under leaf litter when it gets cold. Some move into abandoned burrows dug by other animals. Some species of turtles do not need to dig too deep to escape freezing temperatures. their liver produces a chemical that acts like antifreeze. Just as antifreeze keeps the water in an engine from freezing in the winter, this chemical keeps the turtle’s blood from freezing. Blood carries oxygen throughout their bodies even when everything else is frozen.

Kids: have a question?

Professor Oakley Q. Nutkins
Outside In, Missouri Conservationist
P.O. Box 180
Jefferson City, MO 65102-0180