Fish as feed inputs for aquaculture: practices, sustainability and implications

214 Fish as feed inputs for aquaculture – Practices, sustainability and implications

haddock are farmed in cages in the colder waters of Norway, Iceland and the United

Kingdom. Halibut juveniles are reared in land-based tanks until they are 30–40 g before

they are stocked into sea cages. Unlike salmon, they prefer sheltered areas with little

current movement.

In Europe, eel farms can be found in countries such as Sweden, the United Kingdom,

the Netherlands, France, Spain, Denmark, Italy and Greece. Due to the complexity of

their life cycle, no one has yet managed to successfully breed European eels (Anguilla

anguilla). Instead, eel farms rely on using young eels returning from the Sargasso

Sea to grow. Eel culture or farming involves catching juvenile (glass) eels when they

enter freshwater and growing them to a marketable size. While 95 percent of eels are

grown in freshwater, Italy, the United Kingdom, France and Germany culture eels in

brackishwater (4.5 percent of production) and full seawater (0.5 percent). The three

main techniques for culturing eels include the use of ponds, accelerated temperature

facilities and recirculation systems.

The fattening of bluefin tuna (Thunnus thynnus) has expanded rapidly in the

Mediterranean Sea over the last five years. The Mediterranean Sea farmed tuna production

in 2004 was approximately 23 000 tonnes (FAO, 2005b), of which around 95 percent

was exported to Japan, although the International Commission on Conservation

of Atlantic Tuna (ICCAT) reports that there is currently cage capacity of around

41 000 tonnes (for a six-month growing period). This is mostly in Spain (29 percent),

Turkey (23 percent), Croatia

(16 percent), Malta (15 percent)

and Italy (11 percent), with

lower levels of production in

Greece and Portugal.

In freshwaters, two species

groups predominate, trout and

cyprinids (Figures 3 and 4, Table

2). Trout farming is carried out

commercially in 23 European

states, with annual production

exceeding 60 000 tonnes in

Norway and 35 000 tonnes

in Denmark, Italy, France

and Spain, while Finland,

Germany, Poland and the

United Kingdom each produce

TABLE 1

Marine finfish production in Europe, 1996–2005 (tonnes)

Species 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Seabass 22 334 28 433 37 939 46 157 57 811 56 162 61 093 62 060 68 679 80 161

Seabream 31 132 36 843 48 450 60 831 75 232 79 003 79 767 88 340 88 922 97 060

Salmon 403 284 452 702 502 361 591 068 610 947 640 777 671 655 756 744 717 831 712 271

Sea-grown

trout 87 941 78 025 94 250 98 219 99 282 119 431 144 270 122 987 108 198 101 680

Halibut – 138 20 503 135 389 350 845 855 905

Turbot – 3 118 3 035 3 466 3 873 4 640 5 320 5 107 6 086 6 865

Cod –– –– 16 41 50 2 550 2 600 n/a

Eels 7 594 8 293 10 738 11 109 11 033 10 284 9 033 8 715 8 340 7 800

Total 552 285 607 552 696 793 811 353 858 329 910 727 971 538 1 0 47 348 1 001 511 1 006 742

n/a: Data not available

Source: http://www.feap.info/feap/aquaculturedata/default_en.asp

FIGURE 3

Freshwater finfish production in Europe, 1996–2005

0

50 000

100 000

150 000

200 000

250 000

300 000

350 000

400 000

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Production (tonnes)

Year

Carps Catfish Tro u t