framework of agricultural development.
Rural aquaculture can be practised at
subsistence level as well as at semi-inten-
sive level with varying degrees of cash-
crop orientation.
This paper concentrates on Latin
America, as representative of the devel-
oping world where semi-intensive (shrimp)
and intensive aquaculture (salmon) have
experienced arapid development, whereas
culture-based fisheries are just beginning
to develop. For much of rural aquaculture,
results have been well below the expec-
tations and resources involved.
Aquaculture operations can have both
beneficial and adverse effects on the
environment. Aquaculture can provide a
way to use agriculture wastes to make
marginal lands more productive. Fish
convert plant and animal wastes into high
quality protein and enrich pond mud for
subsequent use on crop land. Aquaculture
can be a major source of fish supply where
inland fisheries have been virtually elimi-
nated because of damming, canalization
and other modifications of the ecosystem.
On the other hand, some freshwater
aquaculture can have negative impacts on
natural habitats and their biota, through
the culture process itself, and on human
health.
Rural Aquaculture
Rural freshwater aquaculture in de-
veloping countries is not normally a source
of environmental pollution but may have
some negative impacts; for example, the
spread of exotic fish species and conse-
quent effects on native species and habi-
tats, loss of genetic diversity, the spread
offish diseases and public health problems
due to unsafe produce, poor working
conditions, waterborne diseases andpara-
sites.
Another important negative impact ofmerous failures of projects aimed at de-
veloping the sector with the purpose of
contributing to a rise in the standard of
living of small-scale fish farmers in devel-
oping countries. Considering that rural
aquacclture is just one activity carried out
by farmers, the negative impact in this
case is not on the environment alone, but
also on the farmer who is also part of the
ecosystem. It is in this context that any-
thing that threatens the sustainability of
aquaculture can be considered as harmful
to the environment. The objective of de-
veloping "environment-compatible" sus-
tainable aquaculture will not be achieved
if most of the development projects fail.
Analysis of social-oriented rural
aquaculture projects (for example, Smith
and Peterson 1982; Engle 1986; Martinez-
Espinosa 1986; Wijkstrijm 1986; FAO-
SIDA 1987; FAO-UNDP-Norwegian Min-
istry of Development Cooperation 1987;
Martinez-Espinosa 1990) concluded that
international assistance had not produced
the expected results at farm level to es-
tablish a self-supporting aquaculture sec-
tor. A change of strategy has been pro-
posed towards institution building, plan-
ning, economics, credit facilitation, etc.,
thereby addressing a range of social fac-
tors.
Rural aquaculture must be considered
as an additional component of agriculture
and should therefore benefit from the wider
experience accumulated in this field.
Special efforts must be made in the iden-
tification of the potential target groups in
aquaculture: development projects, as well
as in the appraisal of the socioeconomic
characteristics. Project formulation based
on wrong assumptions about social, eco-
nomic and political factors are the primary
cause of failures. The main reason for the
high desertion rate has been established
to be the lack of motivation in farmers due
to poor returns with no surplus to com-
mercialize. It is only in very specific cases
rural aquaculture derives from the nu- that the subsistence type of aquaculture,