Fisheries can only be successful in efforts to ensure continuing supplies of fish if excessive fishing is avoided. Fishing communities may place limits on fishing although enhancements and environmentally fishing methods can also be used.
If a river or lake has many species of fish, it is difficult to know if it is being over fished. It probably is being over-fished, if the larger species of fish decline and the smaller fast-growing species take over. When this happens, the number of fish caught may increase, but its value declines and eventually the entire fishery may be threatened. A way to correct over fishing and ensure continued fish supplies is to allocate fishing rights among people who use the waters.
The assignment of fishing rights includes making careful decisions regarding who can fish in the areas and how long their access rights will continue. Once rights are assigned, it must be clear as to who is allowed to fish in a particular body of water regardless of whether they are fishing from boats, from the shore or from rafts.
Many different types of ownership and access rights exist in inland waters. These rights range from complete private ownership of small lakes and ponds to areas that are open to all people. Sometimes access rights belong to local communities or to the government and access is restricted to those who have been granted licenses. In cases where there are no recognized access rights, water resources can be thought of as open to all people. Where access is open to everyone, fishing often provides an occupation of last resort for landless peoples. Fish in open access areas may sometimes be seen as 'famine crops'.
In countries with an established system of fishing rights assigned for long periods, it is in the self-interest of fishers to manage the resource in a sustainable way. Where the rights are assigned for too short a period, commercial fishers may attempt to make a quick profit by overly intensive fishing. This is particularly true where the granting of access rights are the result of an auction (that is, where fishers bid against each other to buy a right to fish for a specific period of time or for a specific amount of fish).
To compliment good ownership and access policies it may be necessary to impose restrictions on fishing gear. Fisheries managers should develop regulations limiting the use of fishing gear and methods that damage fish or their habitats. Damaging gear may need to be banned, but the needs of fishing communities must be kept in mind.
A variety of gear is used in inland waters depending on the type of fishing done, traditions and on water conditions at different times throughout the year. Commonly, more affluent fishers use costly more effective gear, while poorer fishers may only be able to afford simple, basic gear. Care should be taken that poorer fishers are not victimized by gear restrictions.
To supplement gear restrictions, common management policies often involve establishing a minimum length allowed for fish caught. For example, the use of nets with large mesh size may be required so that the smaller fish can escape capture. Likewise, seasonal restrictions on fishing may be set to discourage over fishing and to protect fish during breeding seasons. Conservation or sustainability measures such as controlling over fishing, and restricting gear, season or size restrictions are intended to protect fish populations.
It is also important to avoid wasting fish through spoilage. Fishers need to ensure that harvested fish remain nutritious and of good quality until they are taken to market, sold or eaten. Fishers usually do not have any organized means of keeping the fish fresh between catching and selling. Smoking and sun drying (which result in lower quality) are common methods of preserving fish that are caught well before they reach the market. However, since high use of wood for smoking can result in deforestation, improved methods of preserving fish must be developed.
Inland fisheries require good management of lake and river basins. Industrialization, urbanization, deforestation, mining and agricultural land and water uses often cause degradation of aquatic environments. This degradation is the greatest threat to inland fish production. Many of these threats occur together and interact. They often take place at the level of river and lake basins and also affect coastal areas. It is therefore important that the management of inland fisheries includes environmental issues and the institutional and socio-economic realities of lake and rivers basins.
Basin-wide approaches to the development of policy, legal and institutional management frameworks is necessary to regulate and reduce adverse interactions and conflicts between inland fisheries and other sectors. This type of approach also helps coordinate the planning and management of resources shared by fisheries and other users. Fishery administrators and stakeholders should participate in the formulation and implementation of such basin-wide integrated planning. Stakeholders from all sectors, including fishing communities, should be consulted whenever decisions and plans are implemented that affect the basin as a whole.
Good collaboration between different authorities can lead to the establishment of systems to monitor the basin management process. Such monitoring systems could also prove very useful in preventing adverse transboundary environmental effects in rivers and lakes.
Financing is often an important consideration in ensuring sustainable fisheries. At the local level, purchasing gear and constructing facilities for preserving fish can be expensive. At the regional and national levels, money is needed to regulate and monitor fishing activities, take the necessary rehabilitation and conservation steps for inland waters and research environmental and social impacts in an area. In areas where industrial pollution threatens local fisheries, the costs for controlling sediments and chemicals can be very high. Fishing policies should require polluters to pay these costs.
Small-scale inland fishers are often not able to finance all the measures needed to establish and conduct sustainable fisheries. Governments should work with development banks and other financial agencies to assist small-scale and subsistence fisheries. Since non-fishery users of inland waters have greater access to outside financing, governments might consider organizing finance for management programs as well as anti-pollution programmes from these sources. In this way a financial management plan can be secured for all the users of the aquatic area.
The important guiding principle for inland water development should be that of maximizing benefits from all activities for as many stakeholders as possible while maintaining a healthy environment.