Squatina oculata
The smoothback angelshark is a cartilaginous fish similar to a ray or skate. The species once occurred in waters throughout the Mediterranean Sea and along the eastern Atlantic, from Morocco to Angola. It is no longer observed in many areas of the Mediterranean and is rare throughout the rest of its range. The main threat to the smoothback angelshark is commercial fishing, particularly by demersal fisheries, like trawl fisheries, that primarily operate in depths where the smoothback angelshark occur. In 2016, NOAA Fisheries listed the species as endangered under the Endangered Species Act.
Angelsharks are recognized by their batoid shape (similar to a ray or skate). The smoothback angelshark can be distinguished from other angelsharks by its big thorns, sharp, tooth-like structures on the skin, that are present on the snout and above the eyes, a first dorsal fin that originates well behind the pelvic rear tips, and noticeable white spots in symmetrical patterns on the pectoral fins and body.
Smoothback angelsharks are ambush predators, meaning they lie in wait for prey to pass closely overhead before attacking. They eat small fish, including goatfishes.
Smoothback angelsharks are found in continental shelf and upper slope sediment habitats in the Mediterranean Sea and eastern Atlantic. These sharks are nocturnal bottom dwellers occurring in depths of 66 to 1837 feet and prefer to spend most of their time buried in the sand or mud during the day.
World map providing approximate representation of the smoothback angelshark's range.
Little is known about the growth and reproduction of smoothback angelsharks. Female smoothback angelsharks give birth to live young with a gestation period that likely lasts around a year. Litter sizes range from 5 to 8 pups. Based on the presence of gravid females and young smoothback angelshark, the Gulf of Tunis may be a nursery area for the species.
The primary threat to the smoothback angelshark is overutilization in commercial and artisanal fisheries, particularly demersal fisheries (e.g., trawl fisheries). Historically, angelsharks were so common that fishermen developed a special net designed specifically for catching them. However, over the last 50 years, significant population declines in angelsharks have been observed, with these declines coinciding with the start of trawling activities in the northeast Atlantic and Mediterranean. Because angelsharks are sedentary, bottom-dwelling species, they are highly susceptible to being caught in demersal and trawl fisheries. Consequently, as these fisheries expanded with the use of steam-powered trawlers in the 1890s, angelsharks began to suffer significant declines in abundance throughout their historical range. Evidence of illegal fishing operations have also contributed to declines in smoothback angelshark populations. The species is now considered to be possibly extirpated from the western Mediterranean, and is considered rare throughout the rest of its range in the northeast Atlantic. Because the demersal fisheries that historically contributed to the decline in smoothback angelshark are still active throughout the species’ range and primarily operate in depths where these angelsharks occur, the species remains at risk of overutilization.
| Kingdom | Animalia | Phylum | Chordata | Class | Chondrichthyes | Order | Squatiniformes | Family | Squatinidae | Genus | Squatina | Species | oculata |
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