endemic to a single state or province
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: California endemic: low elevation waters of Sacramento River system, including Pit River up to Pit Falls; Clear Lake, Lake County; Russian River; common in north (Page and Burr 1991), extinct in Pajaro-Salinas and San Joaquin River systems (Lee et al. 1980). Introduced in some small lakes and ponds in California (McGinnis 1984).
Length: 15 cm
Catalog Number: USNM 31186
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes
Locality: Probably From California, California, United States, Pacific
Habitat Type: Freshwater
Comments: Small to large, low-elevation rivers; lakes. Found in a wide variety of habitats, slow or swift-flowing, clear or turbid water, but usually found in sections with emergent aquatic vegetation or overhanging banks, with sand and gravel bottoms (Moyle 1976).
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Comments: Benthic and planktonic invertebrates.
Life History and Behavior
Mating occurs July-September. Sperm stored until January when fertilization occurs. Viviparous; young born in May or June (Moyle 1976). Fecundity varies female size, 20-80 young (Lee et al. 1980). Young sexually mature a few weeks after birth. Lives up to 7 years.
Molecular Biology and Genetics
Barcode data: Hysterocarpus traskii
There are 2 barcode sequences available from BOLD and GenBank. Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species. See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
-- end --
Download FASTA File
Statistics of barcoding coverage: Hysterocarpus traskii
Public Records: 2
Specimens with Barcodes: 2
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Comments: Decline apparently due primarily to habitat alterations (Moyle 1976).
The tule perch Hysterocarpus traskii is a surfperch (Embiotocidae) native to the rivers and estuaries of central California, United States of America. It is the sole member of its genus, and the only freshwater surfperch.
The tule perch is small, at most 15 cm in length, and deep-bodied, with a definite hump shape between the head and the dorsal fin. Color is variable, with a dark back that may have a bluish or purplish cast, and a whitish or yellowish belly. The sides may have a pattern of narrow or wide bars; the frequency of barred patterns varies according to subspecies. The dorsal fin has a noticeable ridge of scales running along its base, and consists of 15-19 spines followed by 9-15 soft rays. The anal fin has 3 spines and 20-16 soft rays, while the pectoral fins have 17-19 rays.
They are fish of the lowlands, inhabiting lakes, sloughs, streams, and rivers, generally in areas with beds of vegetation or overhangs. They generally gather in groups, sometimes in large numbers. Their diet is primarily small invertebrates sucked up from the bottom or picked from the midwater column.
The tule perch occurs in three separate areas in California, which have become differentiated into subspecies:
- Hysterocarpus traskii traskii originally occurred throughout the Sacramento River-San Joaquin River and out into the estuaries around San Francisco Bay, and is still common as far north as the Pit River, although it has mostly disappeared from the San Joaquin basin. The only unbarred fish occur in this subspecies, about 43% existing in this color pattern.
- Hysterocarpus traskii lagunae, the Clear Lake tule perch, is native to Clear Lake and the two Blue Lakes. Although threatened by alien fish introductions and loss of habitat, it remains common in the lake. A broad-barred color pattern is common only in this subspecies, at 27% of individuals.
- Hysterocarpus traskii pomo, the Russian River tule perch, occurs only in the Russian River and the lower parts of its tributaries.
The formal description of the tule perch was first read by W. P. Gibbons at a meeting of the California Academy of Natural Sciences on May 15, 1854, and then published in the San Francisco newspaper The Daily Placer Times and Transcript on May 18, making it a rare case of a new species being published in a newspaper rather than book or scientific journal. Gibbons chose the genus name Hysterocarpus "womb-fruit" referring to the livebearing common to all surfperches, and traskii (sometimes seen as traski) in honor of J. B. Trask who sent Gibbons the first specimens of this fish.
Names and Taxonomy
Comments: Monotypic genus; the only exclusively freshwater embiotocid. Includes subspecies pomo from the Russian River drainage, lagunae from the Clear Lake drainage basin, and traskii from the main Sacramento-San Joaquin drainage; the three subspecies show some genetic divergence (Baltz and Loudenslager 1984). Original spelling ends with -ii (Nelson et al. 2004).
EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.
To request an improvement, please leave a comment on the page. Thank you!