Slimy sculpin | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Scorpaeniformes |
Family: | Cottidae |
Genus: | Cottus |
Species: | C. cognatus |
Binomial name | |
Cottus cognatus J. Richardson, 1836 | |
Synonyms [2] | |
|
The slimy sculpin (Cottus cognatus) is a freshwater species of fish belonging to the family Cottidae, which is the largest sculpin family. They usually inhabit cold rocky streams or lakes across North America, ranging from the Great Lakes, southeast Minnesota, northeast Iowa, southwest Wisconsin and northeast Canada. Slimy sculpins have also been found roaming the cold streams of eastern Siberia. [3] They are commonly confused with their closely related relatives, Mottled sculpin (Cottus bairdi), and with tubenose gobies who are both freshwater fishes as well. The slimy sculpin is a nocturnal fish that usually spends most of its time on the stream bottom and seeks shelter under rocks and logs, especially during spawning season. When it swims, it sometimes appears to be "hopping" along the bottom because of its inefficient ability to swim. This is partly due to the absence of a swim bladder, which normally gives buoyancy to a fish. [3]
The fish has been studied in waters where there is current freshwater acidification. Sculpin were found to be less active and have lower rates of reproduction when found in these waters. For these reasons, slimy sculpin have been identified as a good indicator species for changes in acidification among lakes, ponds, and streams. [4]
Slimy sculpin are native to the United States, Canada, and the Russian Federation. In North America, slimy sculpins are found mainly in Lake Superior and its tributaries, Lake Michigan, and small cold streams found in southwestern Wisconsin, as well as the upper Mississippi River basin. [5] They have also been found in other areas of North America such as southeast Minnesota (mostly in the Mississippi River), northeast Iowa, the upper Columbia River, Alaska, and most all of Canada, especially in Ottawa. Slimy sculpins have also been found in eastern Siberia, Russia. [3]
The slimy sculpin can easily be distinguished by its pair of free and independent pelvic fins, as well as not possessing any scales. [6] The first and second lobed dorsal fins are narrow and touch; the first dorsal fin has 7–9 soft spines while the second has 16–18 fin rays. The lateral line ends below the second dorsal fin and is incomplete, but the lateral line system still helps orient the slimy sculpin in streams by balancing the pressure of currents. The anal fin has 11–13 fin rays and the pelvic fins possess 13–14 fin rays and is in the thoracic position. [7] The mouth and snout are terminal and very wide, and also contain a band of fine conical teeth in both the upper and lower jaw, but do not possess barbels. Adults weigh in around 3-7g and measure up to 6.3–9.1 cm long. The maximum weight of a slimy sculpin is 16.86g and the maximum length is 12.8 cm. [8] When the fish moves, it is an inconsistently rapid and darter-like motion that looks like it's hopping due to its irregular compressed body shape. The sides, back and head of slimy sculpins are dark brown/olive and are mottled with dark irregular blotches and a light cream/white belly. If slimy sculpins lie motionless for a while they camouflage in so well with their surroundings that it is almost impossible to distinguish them. [8] Although they don't have any scales, they do have a few fine prickles anteriorly below the lateral line. [2] Slimy sculpins often look very similar to the tubenose goby as well.
Slimy sculpins often inhabit swift rocky-bottomed cold streams, oligotrophic lakes, and even brackish waters at a preferred temperature range of 9-14 °C. [9] Nocturnally active fishes, they usually roam around in deeper waters ranging from 37–108 meters deep. [8] During the breeding season, females often lay their eggs under sheltered areas like large objects such as rocks or tree roots found at the bottom of lakes or streams that males will guard.
Males often become dark on their backs and sides, and orange on their first dorsal fin during mating season. [6] Males having orange on their first dorsal fin during breeding season is a survival disadvantage, meaning that they can be more easily preyed upon, yet still survive- showing to females that they are fit and have high reproductive success, therefore females are more attracted to these visually distinctive males. Males find nesting sites about 12 cm wide for females, and attract them to these nesting sites until spawning occurs which usually takes place in late April and May under protected areas such as stones or tree roots. [7] Once the eggs are laid, males drive the females out and lure a new female into the nest to lay her eggs. Males then protect the nest for 3–4 weeks containing many females' eggs until all of the eggs hatch. Male slimy sculpins have also been seen protecting their young after hatching as well. [2] Slimy sculpins live up to 4–7 years.
The primary food slimy sculpin prey on is invertebrate benthic insects, which make up 85% or more of their diet, but has also been known to eat crustaceans, fish eggs, and small fish. The invertebrate benthic insects on which the sculpin prey includes aquatic insects such as mayflies, caddis flies, stoneflies, and dragonflies. [5] Predaceous fish that eat slimy sculpin are lake trout, brook trout, salmon, northern pike, and burbot that are native to cool freshwater streams just like the slimy sculpin. There is speculation that sculpins have been known to prey on trout egg that were loose from the redds. However, sculpins predation on stoneflies has reduced stonefly predation on trout eggs and their young. [8]
This species is currently at low concern for conservative action and does not need protection or major management plans. [3]
The spoonhead sculpin is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. This species is widespread in northeastern North America.
The lake chub is a freshwater cyprinid fish found in Canada and in parts of the United States. Of all North American minnows, it is the one with the northernmost distribution. Its genus, Couesius is considered monotypic today. The genus was named after Elliott Coues, who collected the holotype specimen.
The Arctic lamprey, also known as the Japanese river lamprey or Japanese lampern, is a species of lamprey, a jawless fish in the order Petromyzontiformes. It inhabits coastal freshwater habitat types in the Arctic. Some populations are anadromous, spending part of their lives in the ocean. It is the most common and widespread lamprey in the Arctic region.
The deepwater sculpin is a species of freshwater fish in the family Cottidae of order Scorpaeniformes. It is a glacial relict, native to a limited number of deep, cold lakes in Canada and the United States.
The mottled sculpin is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. This species has a wide but scattered North American distribution.
The Pacific staghorn sculpin is a species of marine ray-finned fish belonging to the family Cottidae, the typical sculpins. This species is found in the eastern Pacific Ocean. It is the only species in the monospecific genus Lepidocottus.
The European bullhead is a freshwater fish that is widely distributed in Europe, mainly in rivers. It is a member of the family Cottidae, a type of sculpin. It is also known as the miller's thumb, freshwater sculpin, common bullhead, and cob.
Eldon's galaxias is an endangered galaxiid fish endemic to New Zealand. One of several fishes in the genus Galaxias found in Central Otago, it has a very small home range and is at risk of being driven to extinction by trout introduced for recreational fishing.
The alpine bullhead or Siberian bullhead is a species of freshwater fish in the family Cottidae of sculpins. It is found in China, the Czech Republic, Denmark, Finland, Germany, North Korea, Moldova, Norway, Poland, Romania, Russia, Slovakia, Sweden, and Ukraine. This fish is listed as being of "Least Concern" by the IUCN.
The fourhorn sculpin is a species of ray-finned fish belonging to the family Cottidae, the typical sculpins. This species has a Holarctic distribution and can be found in marine, brackish and fresh waters.
Semotilus atromaculatus, known as the creek chub or the common creek chub, is a small minnow, a freshwater fish found in the eastern US and Canada. Differing in size and color depending on origin of development, the creek chub can usually be defined by a dark brown body with a black lateral line spanning horizontally across the body. It lives primarily within streams and rivers. Creek chubs attain lengths of 2–6 inches (5.1–15.2 cm) with larger specimens of up to 12 inches (30 cm) long.
The banded sculpin is a freshwater fish dwelling mostly in small to moderate sized streams in areas of swift current. Young and juvenile C. carolinae can mainly be found in pools, riffles, and other shallow habitats while adults tend to prefer deeper waters. C. carolinae primarily eats insects and insect larvae, but their large mouths enable them to eat prey nearly as large as themselves, including other sculpin. To prevent predation, including by other fish, the color and pattern of the sculpin tends to match its environment. Most Cottus carolinae are mottled brown with dark vertical banding and usually reach about three inches in length. They have a broad head which rather quickly narrows into a slim body, giving them the appearance of a tadpole reaching adulthood.
Etheostoma exile, the Iowa darter, is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to the lakes and streams of Iowa, along with about 17 other species of darters.
The eastern elliptio is a freshwater mussel in the Unionidae family, native to Canada and the United States. It is a bivalve member of the phylum Mollusca. Not only is it found in Canada and the United States, but it is frequently the most abundant species of mussel found in its home waterways. It is the most common mussel in the Delaware River and the most common mussel found in the state of New Hampshire and Vermont. It can be found in the substrate at the bottom of lakes, ponds and rivers. Size is variable, but can reach up to 13 centimetres (5.1 in) in length.
Percopsis omiscomaycus, also known as the trout-perch, the grounder or the sand minnow, is one of two species in the family Percopsidae. Its name comes from the Greek root words perc, meaning perch and opsi meaning appearance. The species name omiscomaycus is thought to be derived from a Native American word meaning trout. These are freshwater fish that prefer clear to slightly turbid water, and are found in rivers and lakes throughout North America. They are a generally small fish found in deep waters by day, but which migrate to shallower waters at night.They are most often seen washed up on beaches and are rarely seen alive or correctly identified. The trout-perch possess characteristics similar to both the trout and the perch. They are an important source of food for many predator fish such as walleye, northern pike, and lake trout. They are not a major human fishery, but are occasionally used as a bait fish.
The Coastrange sculpin is a freshwater sculpin of the genus Cottus. They are commonly found near the ocean in western North America, namely Canada and the United States. It is also known as the Aleutian sculpin.
The prickly sculpin is a species of ray-finned fish belonging to the family Cottidae, the typical sculpins. It is native to the river drainages of the Pacific Slope of North America from Seward, Alaska south to the Ventura River of Southern California. It extends east of the Continental Divide in the Peace River of British Columbia. It has also been introduced to several reservoirs in Southern California.
The shorthead sculpin is a species of fish in the family Cottidae. Shorthead Sculpins are bottom-dwelling small fish, typically sizing around 13 to 15 cm long. They have large heads and fanlike pectoral fins. They have 7-9 dorsal spines, 15-19 dorsal soft rays, and 10-14 anal soft rays. Narrow caudal peduncle. Palatine teeth and coloration being dark brown and yellow.
The inland riffle sculpin is a species of fish in the family Cottidae. It is found in the United States, inhabiting the lower Columbia River drainage in Washington, to Morro Bay in California. It is also found in the Puget Sound drainage in Washington. It reaches a maximum length of 11.0 cm. It prefers rocky riffles of headwaters and creeks.