Fishing and the environment: why the two are inextricably linked
It was American ecologist Aldo Leopold who said 'harmony with land is like harmony with a friend; you cannot cherish his right hand and chop off his left.' This sentiment rings true in angling. You cannot enjoy good fishing without taking great care of the environment in which you fish. Angling and the environment are inextricably linked and a flourishing aquatic and terrestrial ecosystem is synonymous with good fishing. The majority of anglers not only love and respect the environment in which they fish, but also go to great lengths to protect and conserve the health of the aquatic ecosystem as a whole.
The need for protecting the aquatic environment
The need for environmental protection has never been so great. Our freshwater and marine environments are fragile and impacted upon by a raft of human activities. Our rivers, lakes and streams are under constant threat from agricultural run-off and diffuse pollution, invasive species, siltation, point discharges from sewage treatment works and industrial activity, water extraction, forestry activity and much more.
Rivers are particularly vulnerable to such pressures because as they flow through agricultural land and inhabited areas, they accumulate more and more pollutants which can reach harmful levels in a river's lower reaches. The marine environment is under threat too as commercial over-fishing decimates fish stocks and vast gravel dredgers and otter boards, dragged by trawlers to guide fish into their nets, rip the seabed to pieces destroying fragile communities. There is an array of other environmental pressures influencing both the marine and freshwater environment, not least the impact that a rapidly changing climate is having on all manner of aquatic organisms.
Angling and fisheries conservation
Anglers play an important role in protecting and conserving the aquatic environment. They act as custodians of the waters they fish and are often the first to notice and report pollution incidents or other environmental issues that need addressing. Only this September two fly fisherman in Cambridgeshire noticed, for the first time in Britain, the presence of a highly invasive and ecologically damaging killer shrimp (Dikerogammarus villosus) darting through the shallows of Grafham Water reservoir. The scientific community and the relevant authorities were alerted and rapid steps are now being taken by anglers, scientist and other parties to contain this problematic crustacean before it spreads far and wide.
While the killer shrimp may be bad news, the presence of some invertebrates is very good news. Aquatic invertebrates are extremely sensitive to pollution and so excellent indicators of water quality. One such invertebrate species is Baetis rhodani (the Large Dark Olive) which only thrives in well oxygenated and unpolluted water. Fly fishers routinely observe and record this species and many others and are quick to notice unexpected changes in their abundance that might indicate a pollution incident.
Much of the fisheries research in Britain is stimulated by concerned anglers and fisheries scientists who seek to find answers to key environmental questions. One such question is why have Atlantic salmon (Salmo salar) populations plummeted throughout their range over the past few decades?
The scientific evidence suggests the decline is due to a combination of factors ranging from parasite infestations, arising from the dirty business of some salmon farming, to barriers to fish migration, habitat loss and water quality issues. Anglers have played a key role in the conservation effort by helping to collect data (e.g. scale samples), carrying out habitat restoration work and releasing gravid hen fish destined for their spawning grounds, each of which will deposit around 8200 eggs.