673
property resource through publicly announced
open tender for the benefi ts of the society as a
whole. A societal management body may administer its functions.
32.8 Marketing and Value
Addition
Value addition is an important aspect for achieving
good market price. Accordingly, values are to be
added after proper detailed survey of the societal
needs. Once accepted in the market, the standard
is to be maintained at every cost.
Summary
1. Fishes are primarily adapted cold-blooded
aquatic vertebrates with paired and unpaired
fi ns for locomotion and gills for respiration.
Fish serves as an item of staple food of man in
many regions of the world. Freshwater Fishery
Management ( FWFM ) may be defi ned as the
manipulation of freshwater habitats and fi sh
population to maintain the habitat and to
increase fi sh yield for commercial and recreational uses . The fi shery managers generally
apply a variety of techniques in order to maintain, improve and increase fi sh population.
2. Fishery habitats may be altered to increase
the competitive advantage for desirable
species. Habitat improvement may be done
by the following means.
3. This may include stabilisation of the shoreline of the habitat, improvement of covers for
fi sh and creation of artifi cial spawning sites.
4. Alteration of the water may be done by controlling turbidity aeration and fertility . Such
practices may change the vegetation pattern ,
control spawning and affect predation .
Fishery managers could also alter the fertility
of water by increasing phytoplankton production or by directly adding organic manure .
5. Freshwater habitat may be improved by controlling the associated aquatic vegetation.
The excessive vegetation may be detrimental
to fi shery with regard to the fact that it may
upset the predator – prey relationship. Further,
overlying thick vegetation deprives the
phytoplankton of the needed nutrients, and
eventual decomposition of the same vegetation may result in decrease in the level of
dissolved oxygen . The aquatic macrophytes
may be controlled by mechanical , chemical
or biological means.
6. Freshwater fi shery manager could construct
habitats in the form of reservoirs, artifi cial
lakes, farms, ponds , etc., following specifi c
designs which could allow manipulation of
water level.
7. In addition to manipulating habitat (habitat
improvement and habitat construction), fi shery managers may also manipulate the actual
fi sh population by (i) predator control (b)
competitor control and (c) a rtifi cial propagation , which includes stocking, aquaculture
and breeding of pollution-resistant fi sh.
8. Fishery managers may also manipulate fi sh
population by using various methods of artifi cial propagation .
9. Despite the high biotic potential of the wetlands, the fi shes in them sometimes suffer from
diseases due to various reasons. One such disease found in freshwater fi shes recently is the
Epizootic Ulcerative Syndrome (or EUS)
which has been sweeping the fi shes in epidemic form on a semi- global scale from
Australia to Asia since 1972. As a typical case,
among the fi shes of Sone Beel, there have been
large-scale mortalities since 1988, due to EUS,
affecting about 70 % of the fi sh population.
10. It is obvious that new techniques, specially,
the right attitude towards management , need
to be developed to meet the challenges of the
future.
Suggested Readings
Ahne W, Joergensen PEV, Olsen NH, Wattaravijarn W
(1988) Serological examination of a rhabdovirus
isolated from snakehead ( Ophicephalus striatus ) in
Thailand with ulcerative syndrome. J Appl Ichthyol
4:194–196
Cooper EL (1980) Fisheries management in streams.
In: Lackey RT, Nielsen LA (eds) Fisheries management. Blackwell Scientifi c, Boston, pp 297–322
Suggested Readings
property resource through publicly announced
open tender for the benefi ts of the society as a
whole. A societal management body may administer its functions.
32.8 Marketing and Value
Addition
Value addition is an important aspect for achieving
good market price. Accordingly, values are to be
added after proper detailed survey of the societal
needs. Once accepted in the market, the standard
is to be maintained at every cost.
Summary
1. Fishes are primarily adapted cold-blooded
aquatic vertebrates with paired and unpaired
fi ns for locomotion and gills for respiration.
Fish serves as an item of staple food of man in
many regions of the world. Freshwater Fishery
Management ( FWFM ) may be defi ned as the
manipulation of freshwater habitats and fi sh
population to maintain the habitat and to
increase fi sh yield for commercial and recreational uses . The fi shery managers generally
apply a variety of techniques in order to maintain, improve and increase fi sh population.
2. Fishery habitats may be altered to increase
the competitive advantage for desirable
species. Habitat improvement may be done
by the following means.
3. This may include stabilisation of the shoreline of the habitat, improvement of covers for
fi sh and creation of artifi cial spawning sites.
4. Alteration of the water may be done by controlling turbidity aeration and fertility . Such
practices may change the vegetation pattern ,
control spawning and affect predation .
Fishery managers could also alter the fertility
of water by increasing phytoplankton production or by directly adding organic manure .
5. Freshwater habitat may be improved by controlling the associated aquatic vegetation.
The excessive vegetation may be detrimental
to fi shery with regard to the fact that it may
upset the predator – prey relationship. Further,
overlying thick vegetation deprives the
phytoplankton of the needed nutrients, and
eventual decomposition of the same vegetation may result in decrease in the level of
dissolved oxygen . The aquatic macrophytes
may be controlled by mechanical , chemical
or biological means.
6. Freshwater fi shery manager could construct
habitats in the form of reservoirs, artifi cial
lakes, farms, ponds , etc., following specifi c
designs which could allow manipulation of
water level.
7. In addition to manipulating habitat (habitat
improvement and habitat construction), fi shery managers may also manipulate the actual
fi sh population by (i) predator control (b)
competitor control and (c) a rtifi cial propagation , which includes stocking, aquaculture
and breeding of pollution-resistant fi sh.
8. Fishery managers may also manipulate fi sh
population by using various methods of artifi cial propagation .
9. Despite the high biotic potential of the wetlands, the fi shes in them sometimes suffer from
diseases due to various reasons. One such disease found in freshwater fi shes recently is the
Epizootic Ulcerative Syndrome (or EUS)
which has been sweeping the fi shes in epidemic form on a semi- global scale from
Australia to Asia since 1972. As a typical case,
among the fi shes of Sone Beel, there have been
large-scale mortalities since 1988, due to EUS,
affecting about 70 % of the fi sh population.
10. It is obvious that new techniques, specially,
the right attitude towards management , need
to be developed to meet the challenges of the
future.
Suggested Readings
Ahne W, Joergensen PEV, Olsen NH, Wattaravijarn W
(1988) Serological examination of a rhabdovirus
isolated from snakehead ( Ophicephalus striatus ) in
Thailand with ulcerative syndrome. J Appl Ichthyol
4:194–196
Cooper EL (1980) Fisheries management in streams.
In: Lackey RT, Nielsen LA (eds) Fisheries management. Blackwell Scientifi c, Boston, pp 297–322
Suggested Readings