Fever of Australian cownose rays video-bomb marine research

This extraordinary underwater video of a school of Australian cownose rays (rhinopteridae) – collectively known as a ‘fever’ – shows the richness of life in our protected waters.

Captured using a baited remote underwater video (BRUV) during research at Pimpernel Rock in the Solitary Islands Marine Reserve off NSW’s mid-north coast – the intention was to survey species’ diversity and abundance, and boy - what an abundance!


Snapper, mado and yellowtail scad are seen swimming around the BRUV before a sweep of rays moves into the background.

We estimate a couple of hundred rays are seen flying through the water like a giant flock of underwater birds.

Rob Harcourt captured this photo of a large fever of Australian cownose rays from a helicopter off Sussex Inlet in April 2016.

Recognised by their unusual bi-lobed head, little is known about cownose rays, although we know they swim in large schools to migrate. To see a large fever of cownose rays is amazing, especially towards the southern limit of their distribution.

Their flat, plate-like teeth are used to crush and grind crustaceans and other invertebrates.

The species is dark greyish dorsally (on top) and white ventrally (underneath). It has a single dorsal fin, and a whip-like tail, with one or more serrated spines near the base.

Pimpernel Rock is home to the critically endangered grey nurse shark. While fishing is not allowed within the sanctuary zone, scuba divers are able to swim with this amazing marine life with a permit.

The Pimpernel Rock Sanctuary Zone is seven kilometres off the coast of Sandon Bluffs, NSW, inside the Solitary Islands Commonwealth Marine Reserve.

BRUV surveys have been undertaken at Pimpernel Rock for several years to better understand the type and number of species that inhabit the reserve and to provide a basis for effective management of our reserves.


-Associate Professor Brendan Kelaher Southern Cross University (based at the University’s National Marine Science Centre in Coffs Harbour)