Olive darter facts for kids
Quick facts for kids Olive darter |
|
|---|---|
| Conservation status | |
| Scientific classification | |
| Synonyms | |
|
Etheostoma squamatum Gilbert & Swain, 1887 |
The olive darter (Percina squamata) is a small, freshwater fish. It's a type of darter, which belongs to the same fish family as perches. These fish live in clear, cold rivers and streams in the United States. You can find them in Tennessee, Kentucky, North Carolina, and Georgia.
Olive darters prefer rocky riverbeds in the upper parts of the Tennessee River and Cumberland River systems. They grow to about 5 in (13 cm) long. These fish are insectivores, meaning they mostly eat insect larvae found on the riverbed. Olive darters usually live for about four years and are ready to have babies around age two. They lay many eggs, up to 1500 at a time, which settle into the river gravel.
Sadly, the olive darter is considered a "vulnerable species". This means its numbers are decreasing. Their homes are being harmed by things like habitat destruction and too much dirt in the water (siltation). This often happens because of dams and other changes humans make to rivers. A tiny insect called the hemlock woolly adelgid also harms their habitat by killing important trees near the streams.
Contents
Where Olive Darters Live
Olive darters are found in specific parts of the Tennessee and Cumberland River systems. They live in the headwaters of the Tennessee River. This includes areas like the Holston River and Hiwassee River systems. These locations are in North Carolina, Tennessee, and Georgia.
They also live in the middle parts of the Cumberland River system. This is mainly in the Rockcastle River and Big South Fork areas. These are found in Kentucky and Tennessee. In Georgia, you can only find them in the Toccoa and Little Tennessee River systems.
Olive darters need very good water quality to survive. They like fast-moving water over rocks and boulders. The Toccoa and Nottely rivers in Georgia are perfect for them. They have clear, cold water and rocky bottoms.
What Olive Darters Eat and How They Live
Olive darters are insectivores. This means they mostly eat aquatic insects that live on the river bottom. Their diet includes insects like caddisflies and mayflies. Like many darters, they eat whatever immature insects are available.
These fish prefer streams with a strong current. They like areas with rubble and large rocks. You can often find them in deeper parts of gravelly areas in streams. Sometimes, they are also in shallow pools with rocky bottoms.
It's very important for humans to protect the streams where olive darters live. Human activities can easily harm these special habitats. Things like habitat destruction and introducing new species can change these unique places.
Poor practices in farming and forestry can cause problems. Not controlling soil erosion from construction sites also hurts the streams. More stormwater runoff from cities and factories also pollutes the water. These issues lower the water quality and threaten the olive darters. Runoff and siltation can make the water warmer. This changes the environment the darters need, leading to fewer fish.
Life Cycle and Reproduction
Olive darters can grow up to 5 inches long. They usually live for about four years. Females become ready to reproduce when they are two years old.
They lay a lot of eggs, around 1,500 at a time. This is because the parents don't guard the eggs. The eggs are released into the open water. Then, they fall down and get stuck among the rocks and gravel on the riverbed.
Olive darters usually reproduce between May and July. The females drop their eggs, and the males fertilize them. This way of reproducing helps protect the eggs even without a parent watching over them. Having many eggs also increases the chance that some will survive. This is a common way for many darter species to reproduce.
Protecting the Olive Darter
The olive darter needs clean, fast-moving water in mountain streams. Dams have reduced the places where olive darters can live. The remaining free-flowing streams are at risk from too much dirt and sediment.
Human activities, especially large-scale land development, keep changing the olive darter's home. The olive darter is currently a vulnerable species. This means its survival is threatened by changes to its habitat. Streams are delicate ecosystems. Even small changes can harm them.
Humans are largely responsible for the decline of the olive darter. Not using good land management practices is a problem. Building dams, road crossings, and weirs also creates barriers. These barriers break up the streams. They stop the natural flow of water.
Above a dam, a stream can turn into a lake and fill with sediment. Below a dam, the stream might dry up. If it doesn't dry up, the fish can become isolated. They might be cut off from places to reproduce, food, and the right water flow.
Another threat, not caused by humans, is the hemlock woolly adelgid. This tiny insect kills Eastern hemlock trees. These trees usually grow along stream banks and provide shade. When the trees die, it can lead to more dirt in the water (siltation). This harms the olive darter's habitat.
