The speckled dace (''Rhinichthys osculus''), also known as the spotted dace and the carpita pinta, is a member of the
minnow family. It is found in temperate freshwater in
North America, from
Sonora,
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
to
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
,
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
.
Canada is the northern limit of the speckled dace's distribution, and there it is found only in isolated parts of the
Kettle
A kettle, sometimes called a tea kettle or teakettle, is a type of pot specialized for boiling water, commonly with a ''lid'', ''spout'', and ''handle'', or a small electric kitchen appliance of similar shape that functions in a self-contained ...
and
Granby Rivers. It is possible that, along with the
Salish sucker (''Catostomus'' sp.), the speckled dace was one of the first fish to recolonize the rivers of British Columbia following the
Ice Age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...
. It is believed that
spawning
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquat ...
in Canada occurs once a year during the summer in fish older than two years. During breeding, many males often accompany a single female who broadcasts adhesive eggs over the gravelly
stream bed. Each female produces between 200 and 500 eggs. Speckled dace are
omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...
, feeding upon filamentous
algae and other plant material, bottom-dwelling aquatic insects and
zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...
.
The speckled dace is about long.
Canadian populations of the fish were last sampled in 1977, and then only 400 individuals were collected. Few of the fish caught were adults, suggesting that speckled dace mortality may be high. However, not enough data is available to determine accurately whether the population is self-sustaining or in decline. In Canada, the speckled dace is threatened by its limited habitat and by seasonal flooding.
There are several subspecies, including:
*''R. o. larversi'' - Big Smoky Valley speckled dace
*''R. o. lethoporus'' - Independence Valley speckled dace
*''R. o. moapae'' - Moapa speckled dace
*''R. o. nevadensis'' - Ash Meadows speckled dace
*''R. o. oligoporus'' - Clover Valley speckled dace
*''R. o. thermalis'' -
Kendall Warm Springs dace
*''R. o. velifer'' - Pahranagat speckled dace
*''R. o. ssp'' - Foskett speckled dace
*''R. o. ssp'' - Santa Ana speckled dace
*''R. o. ssp'' - Owens speckled dace
*''R. o. ssp'' - Amargosa Canyon speckled dace
*''R. o. ssp'' - Oasis Valley speckled dace
*''R. o. ssp'' - Long Valley speckled dace
*''R. o. ssp'' - Meadow Valley Wash speckled dace
*''R. o. ssp'' - White River speckled dace
*''R. o. ssp'' - Monitor Valley speckled dace
The Foskett speckled dace, found in "harsh conditions" of the desert waters of the
Great Basin spanning parts of
Southeastern Oregon
Southeastern Oregon is a geographical term for the area along the borders of the U.S. state of Oregon with Idaho, California, and Nevada. It includes the populous areas of Burns, Klamath Falls and Lakeview. The region is also known by its nick ...
and
Nevada
Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...
, has been listed as threatened under the
Endangered Species Act since 1985. From 2011 through 2016, the fish's population fluctuated from a low of 1,728 to a high of 24,888. Prior to listing, the population was estimated to be 1,500 to 2,000. In 2018,
U.S. Fish and Wildlife Service
The United States Fish and Wildlife Service (USFWS or FWS) is an agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats. The mission of the agency is "working with othe ...
officials proposed removing federal protections. Robyn Thorson, the Service's pacific region director, said in a statement; "''We attribute this impressive accomplishment to our partners who have worked so hard on the recovery of the dace. This news builds on other recent successes, including two Oregon fishes that were delisted due to recovery, the
Oregon chub
The Oregon chub (''Oregonichthys crameri'') is a species of ray-finned fish in the family Cyprinidae.
It is endemic to Oregon in the United States. From 1993 to 2015 it was a federally listed threatened species.
This chub is native to the drain ...
and the
Modoc sucker
The Modoc sucker (''Catostomus microps'') is a rare species of freshwater fish native to northern California and southern Oregon. It grows to a length of about and becomes sexually mature at . It feeds on algae, small invertebrates and detritus, ...
.''"
References
* Department of Fisheries and Oceans, Canada, website information on Aquatic Species at Risk.
* https://www.fws.gov/oregonfwo/Species/Data/FoskettSpeckledDace/ Species Fact Sheet / Foskett speckled dace / Rhinichthys osculus ssp.
{{Taxonbar, from=Q2408090
Rhinichthys
Taxa named by Charles Frédéric Girard
Fish described in 1856