Portuguese dogfish

3/9/2019

A Portuguese Dogfish, Centroscymnus coelolepis, from the Wanganella Bank, Norfolk Ridge, Tasman Sea - depth 1445 m. Source: NORFANZ

A uniformly dark dogfish with a golden sheen, this small shark has a stout body that makes it seem like a fancy cigar... sort of. Who are we talking about? The Portuguese Dogfish (Centroscymnus coelolepis) of course!

Found from Cape Hawke in New South Wales to Cape Leeuwin in Western Australia, this small shark is usually observed on or near the bottom of the continental slope in this region, preferring the depths of 270 – 3700 metres. But don't think you can only find this shark in Australia-- it is also found in the western Atlantic, western North Pacific, southern Indian Ocean, New Zealand and eastern Atlantic. Phew! As you can tell, it gets around!

This little cigar-shaped shark has two dorsal fins that are so small and slender that only the tips protrude through the skin. They are covered in large, smooth denticles that sort of make you think of snake skin, as they are leaf-shaped. The Portuguese dogfish has broad pectoral fins, and the first dorsal fin spine is slightly behind these pectoral fins. Like many other sharks, the Portuguese dogfish enjoy eating cephalopods and fish, including other sharks!

They are a viviparous (matrotrophic) species, and litters of 12 – 29 pups. The males of this species mature at 85 cm and females mature at 100 cm. They were once taken as bycatch in Australia, but fishing is now restricted in their home range due to sustainability concerns. However, worldwide they are still fished for its liver oil, fishmeal and for human consumption.

WHAT DID YOU LEARN ABOUT THIS ANIMAL?

GLOSSARY

Continental shelf: Extends from a continent underwater, resulting in a shallow-water area.
Continental slope: The steep slope from a continental shelf to the ocean floor; usually around 20 km (12.4 miles) wide and made up of mud and silt substrate. It is an ideal area for deep sea fishing.
IUCN: International Union for Conservation of Nature.
Oviparity/oviparous: Where adult Chondrichthyans lay eggcases (also known as ‘mermaid’s purses) and the baby develops inside the egg before hatching.