Fishing and angling
Most Polish surface water is used by fishermen and anglers. 28.6 thousand people are employed in fishery, while about 670 thousand people belong to Polish Angling Association (PZW), and this number has been decreasing for last 10 years. This, however, does not reduce the pressure on fish as, according to new regulations, if one wants to fish he or she does not have to belong to PZW but only has to buy a licence. In 1999-2001 over 100 000 short-term permits for angling in lakes were sold annually. Apart from that, the number of people fishing illegally is still increasing.
The main impacts of fishing on environment result from restocking with fry, catching in nets, and actions protecting ichtiofauna and its habitats.
Stocking inland waters with fry has been rising for last 10 years. The most often stocked species are: northern pike (Esox lucius), vendace (Coregonus albula) and tench (Tinca tinca).
Stocking with fish is possible because we learned the biology of fish development and its biotechniques. However, stocking with artificially produced material entails a risk of the change and unification of gene pool and decreased genetic diversity. Improperly conducted stockings may do much harm to fish and the environment. They may endanger dystrophic lakes, and they may transport parasites (especially “wild” stockings). During stocking with fry, alien species are often introduced, which may be a threat to native species. Moreover, the introduction of species which have never been in this environment before is dangerous as this may irreversibly change biocoenotic systems.
Not only fish resources but also water cleanness is protected. There are many protective instruments: law acts specifying close seasons for fish and crayfish or the size of meshes in fishing nets, and the ban on fishing in spawning-grounds as well as on barring spawning migrations.
Catching fish, if conducted properly, allows to maintain the right structure of fish population and regulates the number of fish in the conditions of upset balance, especially when there are too few predators. If the exploitation of fish resources is conducted in a sustainable way, it may not have significant influence on the number of gained species and the biological diversity of ecosystems. However, too extensive exploitation of some populations often takes place. In such a way, the number of cod (Gadus callarias) in Baltic countries has rapidly fallen for last 30 years. During catching fish in nets, the environment of fish may be also damaged, e.g. the bottom of the sea is destroyed because of the technology used.
Fishing and angling involves also the contamination of water ecosystems. The sources of pollution are places of fish breeding and processing, and the waste left by anglers on the seashore. Fishing and angling can destabilize the whole ecosystem, as fish are very important elements in a trophic chain.
In connection with Polish accession to the European Union, the Cabinet accepted the document “Polish Structural Policy in Fishing Sector for 2000-2006”. According to this document, fishing has to adhere to the principle of sustainable development and has to consider non-productive functions to a larger extent.