Jhelum: Awaiting Attention (IV)
Stinking affairs affecting fish population
The Kashmir Times, December 25, 2007
By Athar Parvaiz
Over the years, it has been found that the fish resources of the Jhelum have
diminished to a considerable extent. Experts trace it to more reasons than one.
The introduction of exotic species in the river in an unscientific manner, flow
regulation of the river for generating hydroelectricity, growing pollution,
sedimentation of the riverbed, conversion of large chunks of shallow areas into
the agricultural land and horticultural land; and the excessive extraction of sand
and gravel from the river are said to be the main reasons for decline in fish
resources in river Jhelum.
Most workers conclude that the major threat to sustaining biodiversity and river
fisheries is environmental degradation (Arthington and Welcomme 1995, Coates
1995, FAO 2000, Welcomme 1995, 1997). Human activity over the years in
various segments of the catchment of river Jhelum has significantly increased.
“Deforestation has been rampant and the deforested areas have either been
transformed into farmland (in the lower altitudes) or have simply been rendered
barren. This degradation of the catchment has greatly affected the river system
as the eroded soil and human wastes have found their way directly into the river”,
says Professor A R Yousaf, Head Department Environmental Sciences,
University of Kashmir.
Professor Yousaf, who has carried out a detailed study about the reducing fish
resources of the river, observes that the unscientific introduction of exotic species
into the river is partly responsible for reduction of native species. His study,
which he has recently concluded, observes: “In the early 20th century two Trout
species viz, Salmo trutta fario and Oncorhynchus mykiss were introduced in the
Jhelum and its tributaries in the valley so as to attract the anglers from world
over. Upto that time the human intervention in the river system was negligible
and its drainage basin underwent only natural fluctuations. There was no
deforestation in its catchment. However, the introduction of these species was
not based on any scientific study so as to assess their compatibility with the
native species.”
The study says that both these trout species got established in the upper reaches
of the tributaries in the areas which served as the breeding grounds for the native
Schizothorax species. “The result was the gradual dwindling of the native species
as their eggs and young ones became easy prey for the new entrants both of
which are typical carnivorous organisms”, says the study adding the pressure on
the native species increased with the passage of time as the new introductions
were made under the government patronage.
It goes on to observe: “From 1950s the process of deforestation got accelerated
and significant quantities of eroded soil entered the upper reaches of the
streams, which led to the loss of breeding grounds for the native species… the
exotic species did not suffer much on this account as their population in the
streams was regularly reinforced by the government agencies by releasing fry
and fingerlings raised in the farms. The entry of raw domestic sewage into the
river and its tributaries increased the problems for the native species further.”
As per the study, two more species Cyprinus carpio and Carassius carassius
were introduced in the river, but again without any scientific investigation, which,
coupled with the rapidly deteriorating ecosystem, made the native species to end
up as losers. Flow regulation, which includes dam-building for hydroelectricity
and impoundment of rivers to control floods and provide irrigation water, is said
to be another reason responsible for reduction in fesh resources of Jhelum.
Such an alteration in natural flow regimes causes the obstruction of fish breeding
migrations (e.g, Dudgeon 1995, 2000). The construction of Mangla Dam by
Pakistan in mid 20th century has led to the exit of Tor putitora from the Jhelum,
which according to the Zoologists used to be found upto Sopore on its migration
from the lower reaches of the river.
According to Professor A R Yousaf, the Lower Jhelum constructed at
Gantamulla-Baramulla in 1970s and the Uri-Baramulla barrage constructed in
1990s, though provided with the ladders, but the fish find it difficult to reach the
laddaer as the flow of water at the time of their upstream migration in spring
happens to be very fast and most of the fish are driven back by the current. The
reports from the Lower Jhelum areas suggest that fish get trapped in good
numbers when they start migrating upstream the ladder during springs since the
ladder is often closed.
“In case of the tributaries, large quantities of water are diverted regularly for
migration purposes thereby leaving only small volumes of water in the main
stream bed… over-fishing is also a problem in the flowing zones of the main river
and the mouths of its tributaries like Lidder, pohru etc…. the fishermen
community is not adhering to the mesh size to be used as per the rules. As a
result very small fish are also caught in the net; the gill nets which are not
permitted, are also used for catching the fish”, says Professor Yousaf adding the
fish population has also got adversely affected due to the environmental
degradation and siltation of breeding grounds. “The organic pollution, domestic
sewage, use of pesticides, feretilizers and insecticides for agricultural and
horticultural purposes; and polythene wastes has caused heavy pollution in the
river and its tributaries which has laid an impact on the fish population”, observes
the expert.
According to him, the upper and middle reaches of the streams have also been
greatly exploited by the people over the years and large chunks of shallow areas
have been reclaimed for agriculture and horticulture. Besides, he says, sand and
gravel are regularly extracted from many areas used by the native fish for feeding
and breeding purposes. He further observes that the climatic changes over the
years in the Himalayan region have affected the glacial resources which feed the
river and its tributaries, which has affected the water level in them. “At the time
of spawning (during spring season), the streams are generally full of water
because of melting of snow and the migrating brood fish try to go as upstream
as possible and lay eggs in shallow areas having sandy or gravelly bottom.
However, soon the water recedes as the melting of snow is over. Further, large
volumes of water present in the streams are diverted into irrigational channels.
This leads to drying of the shallow areas and the fingerlings of the fishes get
trapped in pools of leftover water and ultimately get perished after finding no
access to the main stream”, observes Professor Yousuf.
* Athar Parvaiz is the staffer with The Kashmir Times. This is the fourth
article of a series of articles as part of a fellowship awarded to the author
by Centre for Science and Environment (CSE), New Delhi.
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