Notropis bifrenatus

Type: fish

Status: not ranked

Species Guide

Bridle shiner

Notropis bifrenatus

Species Type: fish

Conservation Status: not ranked

IDENTIFICATION

Approximately 2 ½ inches in length with a slender, compressed body. There is a black spot at the base of the caudal fin, usually joined to a brown/black stripe along the side of the body and around the snout where the stripe narrows. The dorsal fin origin is slightly behind the pelvic fin origin. It has a small mouth on a blunt snout.

Distribution & Habitat

The range for this species is from the St. Lawrence River in Quebec in the north to Virginia in the south east of the Appalachians. There are also a few isolated populations within eastern North Carolina and South Carolina. In New Jersey, it can be found within disjunct, isolated populations within the northern and western portions of the state.

Habitat for this species ranges from warm-water small creeks and vegetated ponds to large lakes and rivers with clear to moderately stained water. It is usually found over mud, silt, or detritus in sluggish pools or slow current near moderate flows in streams. It also occurs in tidal and slightly brackish water in the southern portion of its range.

Diet

Bridle shiners are invertivores, consuming aquatic insects and other small invertebrates. Detritus and living plants are also eaten. Like other members of the Cyprinidae family, they are stomachless fish with toothless jaws. Food is chewed by pharyngeal teeth (teeth in the pharyngeal arch of their throat). The pharyngeal teeth are species-specific and are a way to identify some species.

Life Cycle

A schooling species, which is sexually mature at 1 year and has a short life span (about 2 years). Spawning occurs between May and August depending on temperature.

Current Threats, Status, and Conservation

Uncommon and declining. This species may be one of the most critically imperiled freshwater fish species in New Jersey. It is currently found in only a few locations relative to its historic range. It is considered highly vulnerable to habitat change. Due to its short life span, isolated populations risk dying-out due to habitat changes.

In 2016, the New Jersey Endangered and Nongame Advisory Committee recommended an Endangered status for this species, but no formal rule proposal has been filed to date.

 

References

  • Arndt, Rudolf G. 2004. “Annotated Checklist and Distribution of New Jersey Freshwater Fishes, With Comments on Abundance.” The Bulletin: New Jersey Academy of Science. Vol. 49, No. 1.
  • Page, Lawrence M. and B.M. Burr. 2011. Peterson Field Guide to Freshwater Fishes of North America North of Mexico.

Text written by Michael J. Davenport in 2016.

Scientific Classification

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Cypriniformes
  • Family: Cyprinidae
  • Genus: Notropis
  • Species: N. bifrenatus