Striped Smoothhound Shark

About the Species

The striped smoothhound is a shark. The species once commonly occurred off the coast of southern Brazil, but due to significant fishing pressure, particularly on juveniles and newborns by commercial and artisanal fisheries, the species experienced a significant decline. The main threat to the striped smoothhound is bycatch in various commercial and artisanal fisheries operating in its coastal inshore habitat, including nursery areas. In 2017, NOAA Fisheries listed the species as endangered under the Endangered Species Act.

Protected Status

Appearance

The striped smoothhound is one of the most distinctive of the smoothhound shark species, due to its large head, very small eyes and sharply pointed snout. The striped smoothhound is grey or greybrown on its dorsal side and white underneath. Newborns and juveniles have dark bars of uneven widths running across the upper surface of their head and body. Although the distinguishing vertical bars are still present in adults, they are not nearly as defined as they are in juveniles.

Behavior and Diet

Although knowledge of the striped smoothhound’s diet is limited, one study from Brazil suggests the species eats a large amount of crustaceans (mostly boxcrabs), followed by fishes and mollusks.

Where They Live

The striped smoothhound has a very restricted coastal distribution; it lives near the seafloor in depths between 3 and 820 feet along the continental shelf and slope of the southwestern Atlantic in Brazil, Uruguay, and Argentina. During the winter, adults are concentrated in southern Brazil between Rio Grande and Chuı´ off Rio Grande do Sul. In the summer, a portion of the population migrates south to waters off Uruguay and Argentina while the rest of the population remains off the coast of Rio Grande do Sul as year-round residents.

Lifespan & Reproduction

There is very little information on the striped smoothhound’s life history, and the lifespan of the species is unknown. Pregnant females migrate into shallow waters (less than 66 feet deep) along the Rio Grande do Sul coast of Brazil to give birth from October to December after a gestation period that lasts between 11 and 12 months. Striped smoothhounds have 4 to 14 pups per litter, with an average of 8 pups.

Threats

Commercial and artisanal fishing

The primary threat to the striped smoothhound shark is overutilization in commercial and artisanal fisheries. While this species’ naturally low abundance likely prevented a targeted fishery from developing, the striped smoothhound was historically caught (and is still caught) as part of the multispecies smoothhound fisheries. It is also caught as bycatch in fisheries for other species such as drums, flounders, and mullets. These fisheries operate on the Plataforma Sul, off the coast of Rio Grande do Sul, Brazil, which comprises one third of the striped smoothhound’s geographic distribution and is where the species was historically most abundant. In this particular area, the species is vulnerable to numerous fisheries operating in its shallow coastal nursery area.

Scientific Classification

Kingdom	Animalia
Phylum	Chordata
Class	Chondrichthyes
Order	Carcharhiniformes
Family	Triakidae
Genus	Mustelus
Species	fasciatus