3 Aquaculture and Coastal Space Management
89
and mitigated. A substantial body of knowledge exists on the environmental
impacts of aquaculture and this gives excellent insight for allocating aquaculture,
while ensuring least adverse impact. Information on the genetic effects of seabased aquaculture on wild populations through escapees (Naylor et al. 2005) and
cross breeding of wild and cultured organisms (Wier and Grant 2005), nutrient
loading (Karakassis et al. 2005), modification of benthic communities (Karakassis
et al. 2000), heavy metal and persistent organic pollutant contamination (deBruyn
et al. 2006; Mendiguchia et al. 2006; Sather et al. 2006), spreading of disease and
parasites (Bjørn et al. 2001), impacts on seagrasses (Delgado et al. 1999; Ruiz
et al. 2001; Marba et al. 2006), impacts on farm-associated wild fish (Dempster
et al. 2002, 2006) and megafauna (Nash et al. 2000) and a range of other environmental impacts must be considered to assess the suitability of new sites. Capture
of millions of tons of small pelagic fishes to make fish meal and fish oil for
aquaculture feeds (Tacon and Forster 2003) can be considered an “oceanic” impact
which requires fisheries management measures in addition to coastal zone management. Setting “carrying capacities” to determine the overall extent of aquaculture in particular coastal regions is a challenging task, as for many of these
ecological effects, the level of information currently available is insufficient to
determine the extent of the effect.
Once ecological criteria are established, aquaculture can then search for suitable
space that minimizes conflict with the myriad of other users of coastal waters, such
as shipping, fishing, recreational activities and industry (Fig. 3.1). As aquaculture
is the “new kid on the block” in terms of its use of space, in many coastal areas it
will struggle to obtain suitable sites that do not conflict with pre-existing users that
Fig. 3.1 Positive and negative interactions concerning space and environmental impacts between
aquaculture and other coastal users
Fisheries
Transport
Coastal constructions
Biodiversity
Ecosystem carrying capacity
Tourism
−
−
Sewage
Rivers
Pollution
Facilities
+
Pollution
−
Space
−
−
Wild fish Genetic
interactions
−
Fish Farm
+
Nutrients
Food
+
Space
Space
-
Pollution
−
89
and mitigated. A substantial body of knowledge exists on the environmental
impacts of aquaculture and this gives excellent insight for allocating aquaculture,
while ensuring least adverse impact. Information on the genetic effects of seabased aquaculture on wild populations through escapees (Naylor et al. 2005) and
cross breeding of wild and cultured organisms (Wier and Grant 2005), nutrient
loading (Karakassis et al. 2005), modification of benthic communities (Karakassis
et al. 2000), heavy metal and persistent organic pollutant contamination (deBruyn
et al. 2006; Mendiguchia et al. 2006; Sather et al. 2006), spreading of disease and
parasites (Bjørn et al. 2001), impacts on seagrasses (Delgado et al. 1999; Ruiz
et al. 2001; Marba et al. 2006), impacts on farm-associated wild fish (Dempster
et al. 2002, 2006) and megafauna (Nash et al. 2000) and a range of other environmental impacts must be considered to assess the suitability of new sites. Capture
of millions of tons of small pelagic fishes to make fish meal and fish oil for
aquaculture feeds (Tacon and Forster 2003) can be considered an “oceanic” impact
which requires fisheries management measures in addition to coastal zone management. Setting “carrying capacities” to determine the overall extent of aquaculture in particular coastal regions is a challenging task, as for many of these
ecological effects, the level of information currently available is insufficient to
determine the extent of the effect.
Once ecological criteria are established, aquaculture can then search for suitable
space that minimizes conflict with the myriad of other users of coastal waters, such
as shipping, fishing, recreational activities and industry (Fig. 3.1). As aquaculture
is the “new kid on the block” in terms of its use of space, in many coastal areas it
will struggle to obtain suitable sites that do not conflict with pre-existing users that
Fig. 3.1 Positive and negative interactions concerning space and environmental impacts between
aquaculture and other coastal users
Fisheries
Transport
Coastal constructions
Biodiversity
Ecosystem carrying capacity
Tourism
−
−
Sewage
Rivers
Pollution
Facilities
+
Pollution
−
Space
−
−
Wild fish Genetic
interactions
−
Fish Farm
+
Nutrients
Food
+
Space
Space
-
Pollution
−