Acknowledgements 5 Glossary 6 List of Tables 8 List of Figures 9 List of Boxes 10 Pakistan Fact Sheet 11 Executive Summary 12



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8.3 Threats to Freshwater Biodiversity


The widespread destruction of habitats due to the burgeoning human population, pervasive poverty and human consumption patterns has quickened the pace of freshwater Biodiversity loss. In this context, aquatic resources have been relatively neglected. Fish and fish products have provided food and employment in the country. Yet, little effort is made for their preservation.

Domestic waste is probably one of the main sources of organic wastes that mostly enter the riverine system untreated, resulting in high loads of waste reaching the rivers especially in urban areas. Refuse also contributes substantial pollution loads to such rivers. There are additionally, large inputs of organic wastes from agriculture-based industries such as poultry farms, tanneries, textile factories, pulp and paper mills, sugar processing, etc. High concentrations of suspended solids are often present in rivers due to land erosion following deforestation and mining operations.

Although fishermen are required to attain licenses issued by the fisheries departments and to declare their catch, over-fishing continues to pose a threat to native fish species of commercial value.

Many small but valuable wetlands were created by seepage from irrigation systems in the Punjab. However, these are threatened by drainage for agricultural land uses. Other wetlands are under pressure, one the reasons being the discharge of saline water into the wetlands.

Thorough research and investigation are imperative to determine the distribution, taxonomic status, and population size and habitat requirements of these species. Once undertaken, this will enable scientists to list species in relation to their degree of vulnerability, and to devise effective conservation programmes for their protection. With continued urbanisation, a research-based programme aimed at establishing sanctuaries to safeguard the young of vulnerable species during fluvial conditions is necessary

The provincial fisheries departments maintain fish seedling nurseries and release millions of seedlings in the rivers and large ponds. The WAPDA fisheries directorate also does the same in the large lakes of the hydropower projects of the country (Tarbela, Mangla Dams etc). This is performed to supplement natural reproduction and to supply private commercial fish farms. However only fishes of commercial value are reared. Many fish seedling nurseries have also been established in the private sector. During the preparation of this report, the importance of diversifying the release of fish was recognised. Hence, it is hoped that with the functioning of the Biodiversity secretariat, this shall be undertaken after thorough studies are completed in this regard.


8.4 Freshwater Biodiversity Conservation

8.4.1 Strategies and Policies


Agricultural policy, as reflected in the eighth five-year plan, addresses a number of issues relevant to freshwater Biodiversity conservation. The fisheries policy, as reflected in the same plan, focuses on aquaculture and does not refer to the conservation of indigenous aquatic Biodiversity.

Fisheries are dealt with by the provincial fisheries departments, which are limited to the development, protection and enhancement of productivity of commercially important fish species. The fisheries departments protect only 20 out of 164 fish species found in Pakistan. The existing regulation of fisheries is divided between the federal and provincial governments. Provincial fisheries legislation focuses on freshwater and estuarine fisheries. The Sindh Fisheries Act of 1973 is the most developed of the provincial legislation. These laws prohibit the destruction of fish by explosives or by poisoning and regulate fishing craft and gear. It also empowers the government to designate any water body as a sanctuary for fish for a specified period. In such sanctuaries, fish can only be caught with a permit.



The lack of clear jurisdiction can lead to the damage of the resource by a competing government agency despite careful management by the ostensible fisheries authority.

8.4.2 Fish Ladders


Fish travel long distances to breed and feed. They move on to warmer waters in the winter and to clearer waters in the monsoon season. A large number of casualties occur while the fish try to cross the barrages and weirs that are constructed on the river systems. At each headwork, one or two fish ladders are constructed to facilitate a safe passage. Detail of this is given in Table 8.1.
Table 8.1 Fish Ladders in Pakistan

Barrage

Length

Ft

Width

Ft

Bottom floor level R.L.



Upstream

Downstream

Marala

270

10

800

789

Khanki

198

12

738

726

Qadirabad

356

10

692

674

Trimmu

261

12

481

466

Panjnand

187

13

333

319

Sulemanki

270

12

560

549

Kalabagh

234

12

684

667

Chashma

428

30

630

608

Taunsa

262

12

438

423

Source Nazir Bhatti, D.G. Fisheries, Punjab

Personal communication by the Deputy Director Fisheries, Chashma Barrage, where it was also reported for the first time that dolphins occur upstream the Chashma Barrage as well.

Palla (Tenualosa ilisha) fish is most affected by the construction of barrages and dams in the Indus River. Previously its range was from the estuaries of the Arabian Sea to the north Punjab up to the Himalayan foothills.

8.4.3 Additional Research Required


The research conducted so far has mainly focused on freshwater fish, with little attention paid to other components of freshwater Biodiversity. Hence, studies confirm that 160 fish species exist in the different freshwater habitats of Pakistan. The geographic distribution of these fish species is also known. However, this list is not final and considerable research is still required. Further research on fish ladders is also required to make them effective for fish species found in Pakistan.

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