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Circular Stingaree

Circular Stingaree

Urolophus circularis

Stingarees are similar in appearance to stingrays differing only  by their smaller size and having a rounded fin at the end of the tail that is not as whip-like as other rays.  The body (disc) of the circular stingaree is greatly flattened and rounded, with their width being similar to their length.  They have raised eyes with spiracles located behind.  Their name is derived from the distinct pattern of circular white spots and rings on a grey to black background, similar in appearance to the spotted stingaree (Urolophus sp.).  The tail of the circular stingaree carries one or two venomous spines,  and may attack if stepped on or provoked resulting in an extremely painful wound, with venom taking immediate effect.  They are considered one of the larger stingarees, growing up to 60 centimetres.  The circular stingaree is an aplacental viviparous (used to be known as ovoviviparous) species whereby the eggs hatch within the uterus, and the young are not nourished by a placenta, but a yolk sac which is their only food source until their live birth.  They have a low fecundity, giving birth to one to two young each year with a gestation period of 10 months.  Little is known about the life history of this species, however the smallest mature male was found at a length of 53 centimetres.

The circular stingaree is endemic to Western Australian waters from Rottnest Island to Esperance, occurring in shallow seas and subtidal sand and seagrass beds in the eastern Indian waters to depths of 120 metres.  They have a cryptic lifestyle, burying in the sand to hide, with periods of activity both during the day and night and feed primarily on benthic invertebrates.  They are a fast moving species, with the ability to swim as well backwards as it can forwards.

Occurrence at the Busselton Jetty: 

The circular stingaree is rarely observed from the underwater observatory.