While the common ling (also known as the white ling) is by far the most common species of ling in British waters there are two other much less common species of ling – the blue ling and the Spanish ling. While the common ling lives and feeds in offshore waters it is a regular catch for rod and line anglers fishing on boats. The blue and Spanish ling however, live in much deeper waters of several hundred metres all the way down to over one thousand metres and are rarely encountered by humans.
- Scientific name: Molva dypterygia
- Size: Up to 5ft and 30lbs
- UK minimum size: N/a
- UK shore caught record: N/a
- IUCN Status: NE (Not Evaluated)
- Distribution: Found in deep waters around Europe, Greenland and North America. UK/Irish distribution found in the Rockall Trough west of Ireland and the Faroe-Shetland Channel to the north of Scotland.
- Feeds on: Fish found around the seabed such as small cod, haddock and flatfish, will also eat crustaceans and squid.
- Description: Long, eel-like body. Long, slim fins and short first dorsal fin and long second dorsal fin. Colour is generally brown to greyish (despite the name there is only a hint of blue) with a paler underside. Mouth has protruding lower jaw and small, sharp teeth, and the eyes are very large.
The blue ling has a fairly widespread distribution, being found in the Mediterranean, around Scandinavia, Iceland and Greenland and in American and Canadian waters. However, around the British Isles it is only found in the deep waters of the Rockall Trough and the Faroe-Shetland Channel. Blue ling appear to be more common at depths of 500 – 1000 metres, although they have been observed at depths approaching 2000 metres. Like the common ling the blue ling feeds by hunting fish and squid, as well as crustaceans. The body of the blue ling is similar in shape to that of the common ling and the main differences are that the blue ling has larger eyes and a much smaller barbule (the barbule is shorter than the diameter of the eye, whereas in the common ling it is much longer than the eye diameter). The pelvic fins are also much longer and slimmer than those of the common ling. Despite its name the blue ling is not really blue in colour with its name presumably coming from the fact that it is darker than the common ling.
Due to the great depths at which blue ling live they are rarely captured on rod and line, even by boat anglers. Blue ling are commercially valuable and are caught in deepwater trawls. However, blue ling are being overfished and numbers have fallen over recent years – a problem made worse by the fact that trawlers often target this species when they are congregating to spawn, hitting the chances of new generations of this species successfully spawning. There are currently protected areas for this species around Iceland and plans for additional areas closed to commercial blue ling fishing throughout EU waters during the breeding season, and the TAC (Total Allowable Catch) for this species has been reduced in an attempt to allow numbers to recover.
- Scientific name: Molva macrophthalma
- Also known as: Mediterranean Ling
- Size: Up to 4ft and 20lbs
- Feeds on: Like the blue ling the Spanish ling feeds on smaller fish and squid.
- Description: Like all of the ling species the Spanish ling has a long, eel-like body with a small first dorsal fin and much longer second dorsal fin. Pectoral and pelvic fins are long and trailing. Colour is light and can vary between reddish to orange with pale speckles with paler underside. Both dorsal fins and the anal fin are black with white edges, as is the tail fin. Eyes are large and barbule is present, and mouth is full of small, sharp teeth.
The Spanish ling is another species of ling. It is unsurprisingly found in sub-tropical seas closer to the equator and around the Mediterranean, although it is occasionally found south of England and Ireland and in and around the deep water trenches to the west of the British Isles. The Spanish ling comes into shallower water than the blue ling, but still stays offshore in waters deeper than fifty metres and can be found all of the way down to 1000 – 1500 metres. The Spanish ling is also a predator which will feed on all manner of small fish, squid and cuttlefish that it can find, and will also eat crustaceans. The Spanish ling has little commercial value and is not targeted specifically by fisheries, although Spanish ling caught as bycatch may be retained and sold.