Whitefin Swellsharks (Cephaloscyllium albipinnum) are a type of catshark endemic to Southeastern Australia. As a form of protection against predators, members of this genus will swallow water to increase their size, making them look bigger and harder to eat.
Images courtesy of sharkreferences
Other members of the same family are biofluorescent (they glow in the dark!), but it is unknown if this species also have this same adaptation.
Description:
The Whitefin Swellshark is a small stocky species of catshark measuring up to 1.1m (~3 ½ ft) long. Characteristics include:
- Short head with rounded flat snout
- Cat-like eyes positioned high on the head
- 2 dorsal fins, one rounded and the other short and triangular
- Brownish grey coloring with blotchy pattern – is more pronounced in juveniles
- Large caudal fin with distinct lower lobe
- Large mouth with 90-116 upper rows of teeth and 97-110 lower rows of teeth
Image courtesy of fishesofaustralia
Habitat:
Whitefin Swellsharks have a smaller range than other species. They are found in the southeastern part of Australia, with reported sightings in New South Wales, Eucla, the Great Australian Bight, Batemans Bay, and Tasmania.
Image courtesy of Marinewise
It is a bottom dwelling species often found at depths of 126-554m (413-1,817 ft), around the outer continental shelf and upper continental slopes.
What do they eat?
Whitefin Swellsharks are reposted to be nocturnal, hunting for prey at night. They generally eat mollusks, crustaceans, and small bony fish.
Reproduction:
Not much is known about this species reproduction. They are oviparous (egg laying), housing their young in smooth flat-shaped capsules. This “egg” is called a mermaid’s purse. They have a very distinct shape and tough protective layer to keep the developing shark safe prior to hatching.
These sharks sexually mature when the males are 28in long and the females are 39in long.
Image courtesy of Marine Madness
Threats:
The main threat to Whitefin Swellsharks is trawling off southern Australia. Being a bottom dwelling species, they are often caught as bycatch, and either discarded or sold.
Most of its home range is subject to intensive trawling with no current conservation actions in place. An estimate of more than 80% of its population has been decimated within the last 45 years.
This species is currently listed as Critically Endangered by the IUCN AND Overfished by SAFS.
Image courtesy of IUCN Red List