Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal; pH range: 7.0 - ? ; dH range: ? - 15; depth range 0 - 55 m (Ref. 1998). Temperate; 4°C - 18°C (Ref. 2059); 69°N - 34°N
North America: Nova Scotia to Northwest Territories and eastern British Columbia in Canada; Great Lakes-Mississippi River basins south to southern Ohio and Nebraska in USA and west to Montana, USA. Isolated population in Canadian River system in northeastern New Mexico, USA. Introduced elsewhere (Ref. 5723). Introduced in upper Inn drainage in Bavaria, Germany and accidentally in the 1960’s with Micropterus to southern Finland where it has established a population in Lake Lohjanjarvi (Ref. 59043).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 8.7 cm TL male/unsexed; (Ref. 5723); common length : 5.0 cm TL male/unsexed; (Ref. 12193); max. reported age: 2.00 years (Ref. 12193)
Diagnosed from other species of Gasterosteidae in Europe by combination of the following characters: 4-6 short dorsal spines, never inclined to the left or to the right; without keel on side of caudal peduncle; anal fin origin slightly behind dorsal fin origin; body dark olive green (getting blackish in breeding males), with numerous pale spots or undulating bars on flank (Ref. 59043).
Adults inhabit cool, vegetated, sand or mud bottoms of lakes and ponds. Also in pools and backwaters of creeks and small rivers (Ref. 1998, 10294). Rarely found in brackish water. Feed on crustacean and insect larvae, eggs and larvae of fishes, snails, oligochaetes and algae (Ref. 1998, 10294). Preyed upon by kingfishers, herons, and mergansers and occasionally by fishes like Salvelinus fontinalis and Esox lucius (Ref. 1998). Males build, guard and aerate the nest where the eggs are deposited (Ref. 205).
Males arrive first in shallow waters, establish their territories, and build small nests near the bottom. The male then entices the female to the nest and by prodding her ventral and caudal peduncle area, forces her to release her eggs into the nest. The male then drives the female away, fertilizes the eggs and guards his territory until the young hatch and swim away. Males may build two nests during a breeding season and more than one female may deposit eggs in each nest (Ref. 1998). Eggs hatch in 8-9 days (Ref. 59043).
Page, L.M. and B.M. Burr, 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 432 p. (Ref. 5723)
IUCN Red List Status (Ref. 126983)
Threat to humans
Aquarium: commercial; bait: occasionally
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 1.0000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01047 (0.00411 - 0.02665), b=3.07 (2.85 - 3.29), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.2 ±0.1 se; based on diet studies.
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (tmax=2).
Fishing Vulnerability (Ref. 59153
): Low vulnerability (15 of 100).