Pugnose Minnow

Opsopoeodus emiliae

SARA Status
No Status
NS
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

SARA Status

  • No Status NS
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX
COSEWIC
Not at Risk
NR
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

COSEWIC Status

  • Not at Risk NR
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX

Description

The Pugnose Minnow (Opsopoeodus emiliae) is a small, short-lived and somewhat mysterious fish in the carp and minnow family (Cyprinidae). As its name suggests, it has a tell-tale rounded snout, as well as the following other features:

  • small, slender and elongated body, reaching a maximum length of about 6 cm;
  • bluntly rounded snout and very small, upturned mouth;
  • forked tail and short pectoral (behind the head) fins;
  • silvery-coloured with a distinct, thin black line running the full length of each side of the body;
  • criss-cross pattern of scaling on the upper body;
  • nine dorsal rays (spines in the back fin) compared to eight dorsal rays like other Canadian minnows; and
  • spawning males turn dark silver-blue and develop many small, sharp tubercles around the mouth.

Habitat

In Canada, the Pugnose Minnow is only found in southwestern Ontario, where small populations are limited to Lake St. Clair and its smaller tributaries, and the Detroit and Sydenham rivers. Its small numbers have made research on this fish a challenge, and exact sizes of remaining populations in Canada are not known. However, recent monitoring suggests the Pugnose Minnow has been lost from the Thames River, and that its historical range has decreased by more than 80 per cent. In the United States, the Pugnose Minnow is common and widespread, from Texas to Wisconsin and across to South Carolina and Florida.

More research is needed on the biology and preferred Canadian habitat of the Pugnose Minnow, as it is typically found here in areas considered less ideal than where they were historically found—possibly because their ideal habitat no longer exists. For example, Pugnose Minnow used to be found in habitats described as clear, slow-moving, heavily vegetated waters, but are now typically found in warm, turbid (murky), slow-moving waters, with little to no vegetation, over substrates (bottoms) of silt, clay or sand.

The lifespan of the Pugnose Minnow is believed to be three years, and sexual maturity is likely reached at one year of age. The spawning behaviour of this fish is unique compared to other North American cyprinids. In late spring, spawning males choose a flat surface, such as the underside of a rock, and lead females there to lay eggs. The females will lay up to 120 eggs at a time in a single layer along the flat surface and the males guard the nest and eggs from predators. Spawning is repeated many times over six to seven days and the eggs will typically hatch after six days.

The Pugnose Minnow mainly feeds on small aquatic insects such as midges, but may also eat larval fishes and eggs and small aquatic crustaceans such as water fleas. Its upturned mouth suggests this fish is a mid-water or near-surface feeder.

Threats

This species may never have been common in Ontario as it is at the northern limit of its range here. The main threat to the species is loss of clean, well-vegetated habitat. Current threats include increased turbidity, and alteration and destruction of wetlands.

Further Information

For more information, visit the Species at Risk (SARA) Public Registry Profile.

Pugnose Minnow

Pugnose Minnow (Opsopoeodus emiliae) (© Joseph R. Tomelleri)

Illustration of an adult Pugnose Minnow by © Joseph R. Tomelleri

Scientific Name: Opsopoeodus emiliae
SARA Status: Special Concern
COSEWIC Status: Threatened
Region: Ontario

Distribution of Pugnose Minnow in Canada.

Distribution of Pugnose Minnow in Canada.

Did You Know?

This species has recently been re-assessed as Threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). It was previously listed as Special Concern in 2003 under the federal Species at Risk Act and a management plan was developed in 2009. If the species is listed as threatened under SARA, a recovery strategy will be developed.

Pugnose Minnow (Photo credit: Konrad Schmidt)

Photo credit: Konrad Schmidt

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