Blackfin Icefish )

(Chaenocephalus aceratus) Scotia Sea icefish

Appearance

Adult length: 50 - 75 cm


The Icefish is intriguing and almost prehistoric-looking fish, the Blackfin Icefish belongs to the unique Channichthyidae family. Also known as ‘icefish’.


The Blackfin Icefish is one of the most dominant fish species in Antarctica. It has a robust and somewhat elongated body, with a large, slightly flattened head and a fairly long, broad snout which is wider and more rounded at the end. The blackfin icefish’s mouth is relatively large and is equipped with small teeth for grasping its prey.

Habitat and Population

Found only in the Antarctic, the Blackfin Icefish occurs around Bouvet Island and in the Scotia Sea around South Georgia and the South Sandwich Islands, the South Orkney Islands and the South Shetland Islands. It also occurs in the northern part of the Antarctic Peninsula.



The Blackfin Icefish is found in Antarctic shelf waters to depths of 450 metres, although some individuals occur down to depths of 770 metres.

Adult blackfin icefish are mostly bottom-dwelling, but mature adults are known to move inwards to nearshore waters and fjords to spawn. The larvae and juveniles of this species are , typically inhabiting surface waters close to the shore.

Threats


The Blackfin Icefish is caught in relatively low numbers as bycatch in the mackerel icefish (Champsocephalus gunnari) and Antarctic krill (Euphausia superba) commercial fisheries. Despite limitations on the levels of bycatch, the blackfin icefish remains vulnerable to exploitation at different stages throughout its life cycle.It is thought that icefish in general are particularly sensitive to habitat changes due to their highly specialised biology, which allows them to cope with the harsh Antarctic environment.

Diet

The Blackfin Icefish's diet includes Zooplankton

Facts about the Blackfin Icefish

In the freezing waters around Antarctica, the temperature can fall to nearly –2°C. This is below the temperature at which the blood of most fish would freeze. The blackfin icefish has a natural antifreeze in its blood that helps it survive in these conditions. It has no red blood cells and so appears a ghostly white. This makes its blood thinner so that it can flow freely in the cold temperatures. The blackfin icefish is a sluggish hunter of small fish and krill and needs little oxygen.