Yellowfin cutthroat trout
Encyclopedia
The yellowfin cutthroat trout (Oncorhynchus clarki macdonald), a subspecies
of the cutthroat trout
, was officially identified in 1891 and named after the US Fish Commissioner, MacDonald. The yellowfin cutthroat is extinct.
in what is now the state of Colorado
. The two lake
s which formed were named the "Twin Lakes
" by the area's settlers. Both lakes held small greenback cutthroat trout
from the early days of the Wild West, but in the mid-1880s reports circulated of much larger trout, up to 10 pounds (5 kg) in weight, with bright yellow fins.
. They found both the greenback and what they proclaimed to be a new species the "yellowfin cutthroat". In his report Jordan took credit for the name and described the fish as follows:
Jordan's specimens have recently been re-examined by American biologist Robert Behnke, who commented, 'I have no doubt that Jordan was correct; the yellowfin trout and the greenback trout from Twin Lakes were two distinct groups of cutthroat trout'.
to Twin Lakes. The greenback population interbred with the rainbows, resulting in cutbow
s, but the yellowfin disappeared completely. The yellowfin is now extinct.
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the cutthroat trout
Cutthroat trout
The cutthroat trout is a species of freshwater fish in the salmon family of order Salmoniformes. It is one of the many fish species colloquially known as trout...
, was officially identified in 1891 and named after the US Fish Commissioner, MacDonald. The yellowfin cutthroat is extinct.
Natural history
At the end of the last ice-age boulders and clay moraine blocked off a tributary of the headwaters of the Arkansas RiverArkansas River
The Arkansas River is a major tributary of the Mississippi River. The Arkansas generally flows to the east and southeast as it traverses the U.S. states of Colorado, Kansas, Oklahoma, and Arkansas. The river's initial basin starts in the Western United States in Colorado, specifically the Arkansas...
in what is now the state of Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
. The two lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
s which formed were named the "Twin Lakes
Twin Lakes, Lake County, Colorado
Twin Lakes is a census-designated place and a U.S. Post Office located in Lake County, Colorado, United States. The population as of the 2010 Census was 171...
" by the area's settlers. Both lakes held small greenback cutthroat trout
Greenback cutthroat trout
The greenback cutthroat trout is the easternmost subspecies of cutthroat trout. This subspecies, once widespread, today occupies less than 1% of its historical range and is currently listed as threatened under the Endangered Species Act. It was adopted in 1994 as the state fish of...
from the early days of the Wild West, but in the mid-1880s reports circulated of much larger trout, up to 10 pounds (5 kg) in weight, with bright yellow fins.
Discovery and naming
In July 1889, Professor D. S. Jordan and G. R. Fisher visited Twin Lakes and published their discoveries in the 1891 Bulletin of the United States Fish CommissionUnited States Fish Commission
The United States Commission of Fish and Fisheries was established on February 9, 1871 , as an independent commission with a mandate to investigate the causes for the decrease of commercial fish and aquatic animals in U.S...
. They found both the greenback and what they proclaimed to be a new species the "yellowfin cutthroat". In his report Jordan took credit for the name and described the fish as follows:
Color, silvery olive; a broad lemon yellow shade along the sides, lower fins bright golden yellow in life, no red anywhere except the deep red dash on each side of the throat.
Jordan's specimens have recently been re-examined by American biologist Robert Behnke, who commented, 'I have no doubt that Jordan was correct; the yellowfin trout and the greenback trout from Twin Lakes were two distinct groups of cutthroat trout'.
Extinction
Until about 1903, greenback and yellowfin cutthroats survived together in Twin Lakes, the populations remaining isolated as both breeders and feeders. The end for the yellowfin cutthroat came soon after the introduction of the rainbow troutRainbow trout
The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....
to Twin Lakes. The greenback population interbred with the rainbows, resulting in cutbow
Cutbow
A Cutbow is a fertile hybrid between a rainbow trout and a cutthroat trout . While cutbow hybrids may occur naturally, most native populations of rainbows and cutthroats were separated by geography or habitat...
s, but the yellowfin disappeared completely. The yellowfin is now extinct.