First National Report Of Pakistan to the Convention on Biological Diversity Ministry of Environment Government of Pakistan Contents



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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. Alien invasive species remain, however the biggest threat to freshwater biodiversity (please see chapter 8 for details).

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 thereby eliminating the chances of survival of non commercial species. Many fish seedling nurseries have also been established in the private sector.


Alien Invasive Species


A major threat to the fresh water ecosystems has emerged lately with the large scale infestation of fresh waters with alien aquatic species that are highly invasive. Due to the extent of the problem and availability of literature freshwater alien invasives have been discussed in more detail, please see chapter 14 of this book.

Freshwater Biodiversity Conservation


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 plan, focuses on aquaculture and does not refer to the conservation of indigenous aquatic Biodiversity.

Strategies and Policies


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 Ministry of Food Agriculture and Livestock after wide consultations prepared the National Fisheries Policy 2006 that encompasses all the physico-social aspects for better management of the fisheries sector. The Pakistan Wetlands project under implementation by the MOE and WWF envisages the promotion of wise use of wetlands.


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.

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.



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 1998 at Chashma Barrage, where it was also reported for the first time that dolphins occur upstream the Chashma Barrage as well.


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.
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