5 Non-Native Species in Aquaculture
163
production. Approximately 60 species are under aquaculture production, of which
several are introduced from other regions of the world or from other regions of
Australia (see Table 5.1). While many of these species are for human consumption
(e.g., salmonids, oysters and prawns), aquaculture in Australia includes a variety of
products for other purposes.
Non-native species represent 43.3% of Australian aquaculture production by
value (in 2004–05). These non-native species include introduced salmonids
(Atlantic salmon, Salmo salar; Brown trout, Salmo trutta; Brook trout, Salvenlinus
fontinalis and Rainbow trout, O. mykiss), Pacific oysters, and freshwater crayfish
(yabbies: Cherax albidus; C. quadricarinatus) translocated from one Australian
state to another.
Atlantic salmon and rainbow, brown and brook trout are cultured commercially
in Australia. Tasmania is the major force in Australian production. Atlantic salmon
and ocean trout (rainbow trout) are grown in sea cages, trout are also grown in
freshwater dams and raceways where large supplies of cold, flowing water are readily available. Sea cage culture contributes more than 60% of the total salmon and
trout production in Australia.
The Pacific oyster is extensively farmed in Tasmania and South Australia, and
comprises a minor component of the industry in New South Wales where several
native species are grown (Ostrea angasii, Sacostrea cucullata, and S. glomerata).
The farming method is similar to New Zealand where both wooden racks and stakes
are used. The blue mussel, Mytilus edulis, is commercially farmed in Victoria,
Tasmania, New South Wales, and Western Australia.
5.2 Unintentional Aquaculture Related Introductions
of Non-Native Species
Despite the apparent success in increased aquaculture production through the
use of non-native species, current practices can pose significant risks of unintentional introductions from net pens or pond systems into freshwater and
marine systems. These introductions have been widely reported (Naylor et al.
2001; Nico et al. 2001; SAMS 2002) and are often associated with weather
events (e.g., flooding or hurricanes) or accidents of operation. It is estimated
that; up to 2 million farmed Atlantic salmon escape into the North Atlantic each
year (McGinnity et al. 2003), over 500,000 Atlantic salmon escaped from cages
between 1987 and 1997 on the west coast of North America (McKinnell and
Thomson 1997), up to 80% of adult salmon entering rivers in Norway were
escapees (Fiske and Lund 1999) and that the introduced Rainbow trout
Oncorhynchus mykiss now occupies over 51% of Slovenian territory (Povz and
Sumer 2005). Mass escapes of the Pacific white shrimp Penaeus vannemei have
also occurred in both the United States (Balboa et al. 1991; Wenner and Knott
1992; Howells 2001) and Thailand (Barnette et al. 2006).
163
production. Approximately 60 species are under aquaculture production, of which
several are introduced from other regions of the world or from other regions of
Australia (see Table 5.1). While many of these species are for human consumption
(e.g., salmonids, oysters and prawns), aquaculture in Australia includes a variety of
products for other purposes.
Non-native species represent 43.3% of Australian aquaculture production by
value (in 2004–05). These non-native species include introduced salmonids
(Atlantic salmon, Salmo salar; Brown trout, Salmo trutta; Brook trout, Salvenlinus
fontinalis and Rainbow trout, O. mykiss), Pacific oysters, and freshwater crayfish
(yabbies: Cherax albidus; C. quadricarinatus) translocated from one Australian
state to another.
Atlantic salmon and rainbow, brown and brook trout are cultured commercially
in Australia. Tasmania is the major force in Australian production. Atlantic salmon
and ocean trout (rainbow trout) are grown in sea cages, trout are also grown in
freshwater dams and raceways where large supplies of cold, flowing water are readily available. Sea cage culture contributes more than 60% of the total salmon and
trout production in Australia.
The Pacific oyster is extensively farmed in Tasmania and South Australia, and
comprises a minor component of the industry in New South Wales where several
native species are grown (Ostrea angasii, Sacostrea cucullata, and S. glomerata).
The farming method is similar to New Zealand where both wooden racks and stakes
are used. The blue mussel, Mytilus edulis, is commercially farmed in Victoria,
Tasmania, New South Wales, and Western Australia.
5.2 Unintentional Aquaculture Related Introductions
of Non-Native Species
Despite the apparent success in increased aquaculture production through the
use of non-native species, current practices can pose significant risks of unintentional introductions from net pens or pond systems into freshwater and
marine systems. These introductions have been widely reported (Naylor et al.
2001; Nico et al. 2001; SAMS 2002) and are often associated with weather
events (e.g., flooding or hurricanes) or accidents of operation. It is estimated
that; up to 2 million farmed Atlantic salmon escape into the North Atlantic each
year (McGinnity et al. 2003), over 500,000 Atlantic salmon escaped from cages
between 1987 and 1997 on the west coast of North America (McKinnell and
Thomson 1997), up to 80% of adult salmon entering rivers in Norway were
escapees (Fiske and Lund 1999) and that the introduced Rainbow trout
Oncorhynchus mykiss now occupies over 51% of Slovenian territory (Povz and
Sumer 2005). Mass escapes of the Pacific white shrimp Penaeus vannemei have
also occurred in both the United States (Balboa et al. 1991; Wenner and Knott
1992; Howells 2001) and Thailand (Barnette et al. 2006).