Issue
Junior synonym Cottus jaxartensis is a valid species according to Sideleva, 2021 (Ref. 129291) and Cottus nudus is a primary homonyn and permanently invalid (include in Ref. 129291 Quote).
Environment: milieu / climate zone / depth range / distribution range
Ecology
Freshwater; brackish; demersal; pH range: 7.0 - 7.5; dH range: 10 - ?; potamodromous (Ref. 51243); depth range 2 - 2 m (Ref. 58018). Subtropical; 1°C - 16°C (Ref. 45166); 70°N - 40°N, 6°W - 60°E
Europe: North Baltic in Scandinavia south to stream Maurine in southwesternmost of corner of Baltic basin (Germany); lower reaches of streams and rivers and along coast of Sweden, Finland, Russia southwest to Estonia; Danube (except upper tributaries Save and Arges), Elbe, Ems, Weser and Rhône drainages; tributaries of upper Rhine downriver (northward) to about Mannheim; a few of uppermost tributaries of River Tevere, central Italy; Adriatic drainages from Potenza in Italy to Zrmanja in Croatia, except Timavo spring. Locally introduced in Scheldt drainage in Belgium.
Length at first maturity / Size / Weight / Age
Maturity: Lm 4.2 range ? - ? cm
Max length : 18.0 cm TL male/unsexed; (Ref. 556); common length : 10.0 cm TL male/unsexed; (Ref. 556); max. reported age: 10 years (Ref. 74370)
Occurs in cold, clear and fast-flowing water of small stream to medium-sized rivers as well as on gravel or rocky shores of cold lakes and in slightly brackish waters along eastern coast of Baltic coast (Ref. 59043). Feeds on small bottom invertebrates, mainly insects, crustaceans. Pink to yellow eggs are found in clumps attached to undersides of large stones (Ref. 41678). Contrary to statements in older literature, eggs and larvae of fishes are not a common food item (Ref. 45167).
Spawns once a year for several years in low productivity streams, but exhibits multiple spawning within a season in high productivity environments (Ref. 40290, 40754). Male protects several batches of eggs--deposited below a stone--for about 3 weeks. Larvae are not guarded and may occasionally been eaten (Ref. 45166). Also Ref. 26506.
Freyhof, J., M. Kottelat and A. Nolte, 2005. Taxonomic diversity of European Cottus with description of eight new species (Teleostei: Cottidae). Ichthyol. Explor. Freshwat. 16(2):107-172. (Ref. 55856)
IUCN Red List Status (Ref. 130435: Version 2024-1)
Threat to humans
Harmless
Human uses
Fisheries: of no interest; bait: occasionally
Tools
Special reports
Download XML
Internet sources
Estimates based on models
Phylogenetic diversity index (Ref.
82804): PD
50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00933 (0.00553 - 0.01575), b=3.18 (3.03 - 3.33), in cm total length, based on LWR estimates for this species & (Sub)family-body (Ref.
93245).
Trophic level (Ref.
69278): 3.2 ±0.2 se; based on diet studies.
Resilience (Ref.
120179): Medium, minimum population doubling time 1.4 - 4.4 years (tm=1-3).
Fishing Vulnerability (Ref.
59153): Low vulnerability (10 of 100).
