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

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

• establishing responsible management for the most important Chilean fisheries
  
  
  • in order to maintain sustainability, Chilean fisheries are well regulated, with
    restricted access to main fisheries zones; and
  
  
  
  


• developing a sustainable aquaculture industry – aquaculture represents the best
  alternative to increasing production and developing a sustainable national fishing
  industry. For this reason government policies aim to generate and promote the
  best conditions to support the aquaculture industry’s sustainable development,
  on the basis of diversification, production of high-value species for international
  markets, and the development of environmentally sound methods and high
  sanitary standards.
  In this way, Chile has been aiming to strengthen its position as an important fish
  producer. The total Chilean fishery landing in 2006 was 4.91 million tonnes, which
  represents a decrease of 10.4 percent from the previous year and a volume that is
  5.0 percent lower than the average for the period 2001–2005. This volume is provided
  by the productions of two main sources: the capture fisheries, with 4.08 million tonnes,
  and the aquaculture sector, with an estimated production of 822.7 thousand tonnes
  (Figure 3). Trends in Chilean fishery and aquaculture production over the last ten years
  reveal the increasing importance of the aquaculture sector. The 61.4 percent of capture
  fishery production represented by pelagic resources in 2006 is slightly less than the
  62.4 percent registered for the previous year (Figure 3).

2.2 Main pelagic species

The upwelling of subsuperficial colder water towards shallower depths is induced by

the action of the persistent winds that blow parallel to the coast, which in combination

with the earth’s rotation (the Coriolis effect), cause a displacement of the surface

waters and their movement away from the coast. When this movement takes place,

the superficial water displaced towards the open sea is replaced by deep waters,

causing a reduction in the superficial temperature of the sea. This water, which is

usually abundant in nutrients, enriches the superficial layer, allowing a high primary

production (CONA, 2006).

This upwelling phenomenon occurs along a great part of the Chilean coastline as a

result of the north-south shore orientation and the wind direction (Strub et al., 1998).

However, it is usual that these processes are specially localized in specific coastal areas,

for example those areas associated with mountainous peaks and capes where there is a

Source: SERNAPESCA (2006)

FIGURE 4

Variation in the main pelagic fish landings in Chile, 1995–2006

0

500

1 000

1 500

2 000

2 500

3 000

3 500

4 000

4 500

5 000

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

Years

Anchoveta Chub mackerel Jack mackerel

South American pilchard Araucanian herring

T housand t onnes