Sacramento blackfish facts for kids
Quick facts for kids Sacramento blackfish |
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|---|---|
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| Conservation status | |
| Scientific classification | |
| Genus: |
Orthodon
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| Species: |
microlepidotus
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| Synonyms | |
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Leuciscus microlepidotus Ayres, 1854 |
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The Sacramento blackfish (Orthodon microlepidotus) is a type of freshwater fish found in central California. It belongs to the carp family and is the only fish in its special group, called a genus.
Contents
Where They Live
Blackfish mostly live in warm, cloudy waters. You can find them in the Central Valley, in places like slow-moving streams and oxbow lakes. These waters are connected to the Sacramento and San Joaquin Rivers.
They are also common in Clear Lake, the Pajaro River, and the Salinas River. Small creeks that flow into San Francisco Bay are also home to them. Some blackfish live in the Russian River, but they were likely brought there by people.
Blackfish also do well in reservoirs, which are man-made lakes. They have spread to many California reservoirs through the California Aqueduct. They even reached Nevada through the Lahontan Reservoir in 1964. From there, they moved into the Humboldt River area.
What They Look Like
Sacramento blackfish get their name from their shiny black color. Younger fish are more silver, but they get darker as they grow older. Their scales are very small. If you count them along their side, there are usually 90 to 114 scales.
Their forehead is straight, and their eyes are small. Their mouth points upwards. The fin on their back, called the dorsal fin, starts just behind their belly fins, known as pelvic fins. The dorsal fin has 9 to 11 rays, while the anal fin has 8 to 9 rays. The pelvic fins have 10 rays.
Their throat teeth, called pharyngeal teeth, are long, straight, and shaped like knives. This is special and not seen in other similar fish in California. The part of their mouth they use to grind food is quite narrow.
Adult blackfish usually grow to about 35 centimeters (14 inches) long. Some have even been found to be as long as 55 centimeters (22 inches)!
How They Eat
Unlike most North American carp, Sacramento blackfish are filter feeders. This means they strain tiny bits of food from the water. They eat small water creatures called zooplankton, tiny water plants (algae), and floating dead bits. Their diet includes tiny animals like rotifers, copepods, and cladocerans, as well as tiny plant-like organisms called diatoms.
Younger blackfish pick up food items one by one. But adult blackfish mostly use their mouth and gills to filter food from large amounts of water. They open and close their mouth quickly to pump water through. The food bits get caught in a sticky patch of mucus on the roof of their mouth. This mucus is made by a special organ. Then, the fish swallows the food bits along with the mucus.
Bigger blackfish have larger mouths, which makes filter feeding easier for them. Because of this, larger blackfish don't chase individual food items like smaller blackfish do.
Life Cycle and Reproduction
Sacramento blackfish usually live for no more than five years. They grow quickly during their first two years. They become adults and can have babies when they are 2 to 3 years old.
The breeding season for blackfish is from spring through early summer. During this time, male blackfish fertilize the eggs laid by females in shallow waters. Having babies can be very tiring for the fish. Many blackfish die after one or two breeding seasons because of the stress. However, some can reproduce up to four times in their lives.
About Their Name and Family
The scientific name for the Sacramento blackfish is Orthodon microlepidotus. The word "Orthodon" means "straight teeth," and "microlepidotus" means "small scales." These names describe two of the fish's unique features.
The Orthodon group (genus) has only one member, the Sacramento blackfish. This means it's a very unique species with no close relatives in its group. Even though it's unique, the blackfish has been known to have hybrid babies with other fish. These include the Hitch and Tui Chubs. These fish are also part of the blackfish's larger family group, called Leuciscinae, and are found in California.
Their Status and Survival
The IUCN, which tracks how well species are doing, says the Sacramento blackfish is of "least concern." This means they are not at high risk of disappearing. Even though there are fewer blackfish in California's Central Valley than before, they are still doing well.
Blackfish are known for being able to adapt to tough environments. They can handle big changes in water temperature. A study by Joseph J. Cech Jr., a professor at the University of California, Davis, found that blackfish can even live in water with very low oxygen levels. This is called a hypoxic environment.
Sacramento blackfish are important for some businesses. They are sold alive in many Asian fish markets in California. People also think they could be a good species for aquaculture, which is like farming fish.
See also
In Spanish: Orthodon microlepidotus para niños
