Leptocottus armatus

Commonly found near shore, especially in bays and estuaries; most frequently on sandy bottom (Ref. 2850). Intertidal individuals breath air when out of water (Ref. 31184). Can leave tide pools if aquatic conditions become inhospitable (Ref. 31184). Although some individuals may spend their entire life in highly saline waters (Ref. 28693), some newly metamorphosed young move from the estuarine spawning sites to completely fresh water and may remain there for up to 6 weeks (Ref. 27547). Adults apparently tend to remain in the shallow lower estuary, or farther offshore (Ref. 27547). Feeds mostly on crabs, shrimps and amphipods, but also takes larval, juvenile and adult fishes, as well as polychaete worms, mollusks and other invertebrates (Ref. 4930). Expands its gill covers and produces a low-pitched humming sound when stressed (Ref. 6885). Considered a nuisance by anglers (Ref. 27547).

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: San Quintin Bay, Baja California, north to Kodiak Island and west to Unga Island, Aleutians, Alaska (Lee et al. 1980).

Eastern Pacific: Izembek Lagoon, on the southeastern Bering Sea coast of Alaska to Bahia San Quintin, northern Baja California, Mexico.

Eastern North Pacific: southeastern Bering Sea to northern Baja Calfiornia.

Dorsal spines (total): 6 - 8; Dorsal soft rays (total): 15 - 20; Analspines: 0; Analsoft rays: 15 - 20; Vertebrae: 37 - 39

Length: 46 cm

Maximum size: 460 mm TL

46.0 cm TL (male/unsexed; (Ref. 2850)); max. reported age: 10 years (Ref. 28936)

Distinguished by the large upper preopercular spine ending in 3 or 4 sharp, upturned, curved spinules and by the large, dark spot on the posterior part of the spiny dorsal fin (Ref. 27547). Gill rakers reduced to flat, bony plates, each bearing a cluster of small teeth; lateral line nearly straight; each pore associated with a small subdermal cartilaginous plate (Ref. 27547). Caudal rounded (Ref. 6885). Grayish olive to rather green, occasionally with some yellow, dorsally; orange-yellow to white or silvery below lateral line; spiny dorsal dusky, with a black spot near tips of last 3 spines, a white band below it; soft dorsal fin dusky, with several oblique white to yellowish bands; pectorals yellow with 5 or 6 dark greenish bars; caudal dusky with one or two pale bands; anal and pelvic fins pale (Ref. 27547).

Habitat Type: Freshwater

Comments: Shallow coastal waters, bays, estuaries, or lower reaches of rivers in salinities of 0-34 ppt; most commonly on sand bottom; ranges to depths of about 90 m. Adults usually inhabit lower estuaries; young found in fresh water in rivers and smaller streams, and in upper and lower estuaries. Most spawning probably occurs in bays and estuaries with relatively stable salinities (Morrow 1980). Hatchlings move into fresh water in spring, move down into estuaries in summer.

demersal; amphidromous (Ref. 51243); brackish; marine; depth range 0 - 156 m

Depth range based on 99 specimens in 1 taxon.
Water temperature and chemistry ranges based on 10 samples.

Environmental ranges
  Depth range (m): 0.04 - 212.5
  Temperature range (°C): 7.819 - 10.476
  Nitrate (umol/L): 4.616 - 20.559
  Salinity (PPS): 31.499 - 33.279
  Oxygen (ml/l): 4.214 - 6.862
  Phosphate (umol/l): 0.748 - 1.826
  Silicate (umol/l): 10.583 - 30.305

Graphical representation

Depth range (m): 0.04 - 212.5

Temperature range (°C): 7.819 - 10.476

Nitrate (umol/L): 4.616 - 20.559

Salinity (PPS): 31.499 - 33.279

Oxygen (ml/l): 4.214 - 6.862

Phosphate (umol/l): 0.748 - 1.826

Silicate (umol/l): 10.583 - 30.305
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Depth: 0 - 156m.
Recorded at 156 meters.

Habitat: demersal. Commonly found near shore, especially in bays and estuaries. Sometimes enters lower reaches of coastal streams. Most frequently found on sand bottom. Feeds mostly on crabs, shrimps and amphipods, but also takes larval, juvenile and adult fishes as well as polychaete worms, molluscs and other invertebrates (Ref. 4930). Spawns in February (Ref. 4925). Eaten by birds, marine mammals and fishes. expands its gill covers and produces a low-pitched humming sound when stressed (Ref. 6885).

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: Yes. At least some 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.

Recently metamorphosed young may move from estuarine areas into fresh water.

Amphidromous. Refers to fishes that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.Characteristic elements in amphidromy are: reproduction in fresh water, passage to sea by newly hatched larvae, a period of feeding and growing at sea usually a few months long, return to fresh water of well-grown juveniles, a further period of feeding and growing in fresh water, followed by reproduction there (Ref. 82692).

Comments: Juveniles feed mainly on benthic organisms (e.g., amphipods, insect larvae, and polychaete worms). Adults consume shrimps, crabs and fish, as well as crustaceans and marine worms (Wydoski and Whitney 1979).

Life span seldom more than 3 years. Mostly a sedentary fish, but may move rapidly on occasion. Eaten by cormorants, sea lions, etc.

Maximum longevity: 10 years (wild)

Mature when one year old. Spawns October-March, usually January-February. Females lay between 2,000 to 11,000 eggs, depending on their size (Moyle 1976).

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Comments: Localized threats may exist, but on a range-wide scale no major threats are known.

Not Evaluated

aquarium: public aquariums