Although the hake is well-known as a European fish, there are up to a dozen similar species found elsewhere in the world’s oceans. The different varieties of hake are distributed along the edge of the continental shelf from Britain southwards to the Mediterranean and then to western and southern Africa. Others occur on the North American Atlantic coast and around the tip of South America and up to California. A further group of species occurs off New Zealand.
In many cases, the ranges of the various species overlap with each other. In the eastern Atlantic it is hard to decide where the northern hake gives way to its Moroccan cousin, or where that species ends and the West African version starts, or where the South African hake takes over from that.
All these hake live in the water of 185m (600ft) deep or less that surrounds each continent, but they also occur in very much deeper water. The European hake, for instance, is most common in depths of 165m to 550m (540-1800ft), but does come closer inshore at times. Its depth range and abundance is affected by commercial fishing. The decline in fishing during World War II meant that hake stocks increased and the species spread into shallow water so that it was possible to catch them on the west coast of Britain within sight of land. Today, fishing pressure is again heavy and very few hake are caught close inshore.
On the move
The hake spawns in spring and early summer off the Irish coast and from May to August off the Hebrides. Spawning is protracted, starting in deep water and gradually moving to shallower water as the season advances. Both the eggs and larvae are pelagic (living in the open ocean, often on the surface) but sometimes drift towards the coast where the young fish can be found in fairly shallow water.
Growth rates depend on how much food is available in the areas where the young fish gather. At the end of their first year they are about 16cm (6V2in) long, in the second around 20cm (8in), and in later years they grow by 8-9cm (3-3%in) a year. Males reach maturity at about four years and females at about eight.
Not fussy eaters
When young, hake feed on tiny crustaceans such as krill – but as they grow they change to a diet composed largely of fish and squid. Many of their food fishes are animals of deep water – such as blue whiting and lantern fish.
When hake come into shallower water during the summer they feed on whiting, Norway pout, herring and mackerel — and even young hake. This suggests that they are not selective feeders but are simply exploiting the most abundant fish of a suitable size. It also shows that much of their time is spent in mid-water.
The hake spends the day close to the sea bed, at night rising to mid-water to feed and, in the appropriate season, to spawn; it also migrates inshore into shallower water in the summer.
Rather few hake are caught by anglers these days and most of the catches made are on the west coast and in the western English Channel. However, as their numbers in inshore waters vary quite a lot, depending not only on the successful survival of year classes, but also on the flow of ocean currents and pressure from commercial fisheries, there is always the possiblity of hake appearing again in some numbers throughout British waters.