Coastal stingaree  (Urolophus orarius)

Classified as Endangered (EN) on the IUCN Red List (1).

The coastal stingaree is a rare endemic of southern Australian waters and is seldom seen in the wild (3). As with most rays, the body of this species is flattened and disc-shaped, with the pectoral fins broadly expanded and fused with the head and trunk. Characteristic of the round ray or stingaree family (Urolophidae), the coastal stingaree possesses a remarkably circular-shaped body disc. Like other rays, this species has a long, relatively narrow tail that is distinctly demarcated from the disc-like body. Most species of stingaree possess one or more long venomous spines about half way down their tail (2). In addition to this defensive poisonous sting, most stingarees have cryptic coloration, which acts as camouflage in the sandy or rocky bottom of their habitat (4). The coastal stingaree is greyish-brown with dark mottling on its upper surface and paler underneath (3).

Restricted to the Eastern Indian Ocean in the waters of southern Australia, where the species is known from the Great Australian Bight Marine Park around to the waters of western Victoria (2) (3) (5).

A marine, bottom-dwelling species found in shallow coastal waters, from depths of 20 to 50 m (2) (4).

Very little is known about the biology of this species (3), but there are certain characteristics known to be typical of stingarees (Urolophidae) which the coastal stingaree is likely to possess. This family of rays only has one litter a year, sometimes one every two years, and usually gives birth to between two and four live young per litter. Since so few young are produced, it is important that they survive. Thus, extended nurturing inside the mother’s body produces large young able to feed and fend for themselves, with no reported evidence of post-birth parental investment. Some stingaree species have a gestation period of around three months, which usually occurs at some point across spring, summer and autumn. Many stingarees feed on bottom-dwelling fishes, worms, shrimp and other small organisms in the substrate around them, with some species able to eat hard-shelled mollusks and crustaceans (4).

Stingarees are rarely targeted by fisheries or sold commercially, but large numbers are caught incidentally as bycatch. Because of their low birth rates, slow reproductive turnover and sometimes restricted range, stingarees are particularly susceptible to the damaging effects of over-fishing (4).

The coastal stingaree occurs in the Great Australian Bight Marine Park (GAB), within which exists a Benthic Protection Zone (BPZ) that affords some degree of protection to this bottom-dwelling species. However, the Park’s mission is not only to maintain current levels of biodiversity, but also to provide ecologically sustainable use of marine resources. As such, a number of fisheries and recreational fishing are still permitted to operate in certain areas, and exploratory drilling for petroleum commenced in 2003 and further exploration activity is anticipated in the future (5). These activities may threaten the coastal stingaree, and there are currently no conservation measures directly targeting the species.

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the conservation of sharks and rays see:

• Save Our Seas Foundation:
  http://www.saveourseas.com
• Project Aware:
  http://www.projectaware.org/