Cutthroat trout
Cutthroat trout, a member of the Salmonidae family, are freshwater fish primarily found in lakes and rivers throughout the western United States, extending from the Rocky Mountains to the Pacific coast. This species is notable for its various subspecies, including the Yellowstone River and Snake River cutthroat trout, each named for their specific habitats. Characterized by their distinctive red markings beneath the jaw, which resemble injuries, cutthroat trout possess elongated bodies, forked tails, and soft-rayed fins.
These fish can exhibit both freshwater and anadromous behaviors, with some migrating to saltwater to spawn. Spawning typically occurs in the winter and spring, with the fish reaching maturity around three to five years of age. However, cutthroat trout populations face challenges; they struggle to coexist with other fish species and are susceptible to hybridization. Conservation efforts, particularly in places like Yellowstone National Park, are underway to protect cutthroat trout from non-native species. Their diet primarily consists of freshwater shrimp and insect larvae, and they can live up to nine years, with larger individuals found in open water environments.
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Cutthroat trout
Cutthroat trout are found in lakes and rivers. There are many subspecies of this species and their names reflect the places where they are found, such as the Yellowstone River and Snake River cutthroat trout.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Salmoniformes
Family: Salmonidae
Genus: Oncorhynchus
Species: Clarki
The bodies of the cutthroat trout are normally five times as long as they are deep. They have forked tails and soft-rayed fins. Soft-rayed fins consist of several soft, finger-like spines held together with a web-like material. Outside and below the lower jaws, red markings are visible. These red markings make the fish appear as if they have suffered injuries to their throats and are the reason for the name, cutthroat. The teeth of these fish are located toward the backs of their tongues.
Cutthroat trout inhabit rivers and lakes and some, called anadromous, move from freshwater to saltwater to lay their eggs. Cutthroat trout populations have grown smaller in many areas for two reasons. First, cutthroat do not live well with other fish species and struggle to feed in areas with limited food supply. Second, cutthroat trout frequently mate with other fish species. The result is hybrid fish, or those which share the characteristics of two fish. These hybrid fish are not included in the cutthroat population. Humans have brought cutthroats to eastern waters to increase the population, but their survival rate is low. In the early 2020s, Yellowstone National Park began removing non-native fish from the Yellowstone Cutthroat's habitat to protect the species.
Cutthroat trout spawn in the winter and spring, with coastal fish spawning in February and March. Cutthroat trout living farther inland spawn in April and May. Spawning is the process by which female cutthroat trout lay their eggs on the bottom of a stream or river. After laying the eggs, the male cutthroat trout fertilizes them. Spawning begins around age four and occurs every other year afterward. At three to five years old, the fish reach maturity, and some cutthroat trout leave the river or stream for the open ocean. These anadromous fish return to freshwater after one to two years in saltwater.
Lake-dwelling cutthroat trout have been known to reach a weight of 41 pounds (19 kilograms). The largest subspecies of cutthroat trout is the Lahontan cutthroat trout (Oncorhynchus clarkii henshawi), which measures 8 to 22 inches (20 to 55 centimeters) if they live in open water. The Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) is a mid-size cutthroat subspecies that may be 6 to 26 inches long (15 1/4 to 66 centimeters) and weigh 2 pounds (almost 1 kilogram). The westslope cutthroat trout (Oncorhynchus clarkii lewisi) is a smaller subspecies. They grow to 6 to 16 inches (15 1/4 to 40 1/2 centimeters) long and average 1 1/2 pounds (3/4 kilograms). In general, fish living in inland waters usually do not exceed 5 pounds (2 1/4 kilograms), while costal and open water fish average 4 pounds (2 kilograms).
Cutthroat trout are found from the Rocky Mountains west to the Pacific coast and from northern California to Alaska. Their diet includes freshwater shrimp and insect larvae. One study in Henrys Lake in Idaho showed shrimp, damselfly nymphs, and midges made up 90 percent of the trout’s food. Cutthroat trout that inhabit saltwater feed on sand lances, shrimp, and an assortment of fish found in shallow water. Here, the trout is often caught by fishermen.
The life span of cutthroat trout is six to nine years.
Bibliography
"Cutthroat trout (Oncorhynchus Clarkii)." Washington Department of Fish and Wildlife, wdfw.wa.gov/species-habitats/species/oncorhynchus-clarkii. Accessed 5 Apr. 2024.
Spaete, Lucas. "Oncorhynchus Clarkii." Animal Diversity Web, animaldiversity.org/accounts/Oncorhynchus‗clarkii. Accessed 5 Apr. 2024.