Northern madtom facts for kids
Quick facts for kids Northern madtom |
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The northern madtom (Noturus stigmosus) is a small freshwater fish. It is part of the catfish family. This fish is quite rare, which means scientists don't know a lot about it.
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Where the Northern Madtom Lives
The northern madtom lives in the Ohio River valley. You can find it in parts of Canada and the Northeastern United States, all the way down to Tennessee. In Canada, it is considered an endangered species.
This fish likes places with fast-moving water. It prefers areas with sand, silt, or rocky bottoms. It can live in water that is a bit cloudy. However, it cannot survive in water with a lot of pollution from dirt or mud. Keeping the water clean is very important for these fish to have babies.
In most places, the northern madtom is found in only a few streams or creeks. For example, in Pennsylvania, it lives in just one creek. Because of this, it is often called "critically imperiled," which means it's in great danger. In Tennessee, it is a bit more common, but still needs special care.
What the Northern Madtom Eats
The northern madtom eats small insects and other tiny invertebrates. Because there are so few of these fish, scientists haven't learned much about their exact diet. We don't know how much or what specific types of food they eat.
Northern Madtom Habitat
Northern madtoms live in different types of places depending on where they are. In the northern parts of their range, like Canada, they live in larger rivers. They can even be found in some lakes, such as Lake St. Clair.
Further south, like in Tennessee, they usually live in smaller creeks and streams. These smaller waterways have a moderate current. No matter where they live, northern madtoms always prefer areas with sand, gravel, or rocky bottoms. They can handle some cloudy water, but they avoid places with a lot of mud or silt.
Sometimes, northern madtoms share their homes with other fish. Some of these are similar species, while others are invasive species. Invasive species can compete with the northern madtoms for food and living space. However, scientists don't know much about how this competition affects the northern madtoms.
Northern Madtom Reproduction and Life Cycle
Northern madtoms get ready to have babies in early summer. They only start to lay eggs when the water temperature reaches about 23 degrees Celsius (73 degrees Fahrenheit).
They are thought to have only one group of eggs each year. A female can lay between 32 and 160 eggs. This wide range might mean that females lay eggs in more than one nest.
Northern madtoms are "cavity nesters." This means they build their nests in hidden spots. They have been found making nests under large rocks, logs, and even inside holes dug by crayfish. Sometimes, they even use human trash like bottles, cans, and boxes for their nests!
The male northern madtom guards the eggs. After the eggs hatch, the male continues to protect the baby fish for about one month. Young northern madtoms are usually found in water that is warm, has a good pH level, and enough oxygen. The water depth and speed also need to be just right.
Protecting the Northern Madtom
The northern madtom is listed as "vulnerable" at the federal level. This means it could become endangered if its situation doesn't improve. In many states, especially in the northern areas, it is listed as "critically imperiled." This is because there are so few of them, and they are spread out in small groups. This also suggests that they need very specific places to live. They are very sensitive to changes in their habitat.
One of the main reasons the northern madtom is declining is the loss of good places to live. This happens when people change the land for buildings or farms. Building small dams in creeks where they live also hurts them. More dirt and mud in the streams also negatively affect these fish.
Because scientists don't know much about what the northern madtom needs, there aren't many specific plans just for them. Current efforts focus on protecting their natural homes. This includes keeping stream flows steady, preventing riverbanks from washing away, and stopping dirt from building up in the water. Scientists try to count the fish using nets and traps. However, because they are so rare, it's hard to learn a lot from these counts.
See also
In Spanish: Noturus stigmosus para niños
