The death of wild salmon

The last few decades have seen an enormous increase in the number of salmon farms in countries bordering the north Atlantic. This proliferation is most marked in two countries famous for their salmon, Norway and Scotland. Salmon farming in Norway and Scotland has expanded to become a major industry and as the number of farmed salmon has exploded, the population of its wild relatives has crashed. The rivers of these countries that used to have such great summer runs of fish every season that they used to attract thousands of anglers from all over the word are now in perilous decline. Recently Truls Halstensen, a Norwegian fishing writer, wrote that his local river, the Driva, where he used to be able to catch five or more fish of over 20 pounds  weight in a morning, is now almost totally fishless.

The link between the increase in farmed salmon and the decline in the wild population is hotly disputed. Environmentalist claim that the increase in farming has affected wild salmon and the sea environment in various ways. Firstly it is claimed that the mass escapes of farmed fish present a grave threat to the gene pool of wild salmon stocks. Escapees breed less successfully than wild salmon but the young of the escapees, known as parr, breed aggressively and can produce four times more successfully than their counterparts. The parr, bred by escapees also become sexually active far sooner than wild salmon stocks. Jeremy Read, director of the Atlantic Salmon Trust points out that "the major problem of interbreeding is that it reduces a population's fitness and ability to survive. Native salmon have evolved to meet the circumstances and habitat of sea and river life. Farm fish are under very different selection pressure in an artificial habitat. This could leave the world with a north Atlantic salmon which could not survive in its native conditions.". The huge increase in sea lice in coastal waters in another growing problem. Sea lice thrive in salmon farm conditions and their increase in numbers means that wild salmon and other fish entering waters where there are farms can fall prey to the lice.

Another difficulty and one  of the most worry side effects of the salmon farm industry is that salmon farmers cannot function without vast quantities of tiny sea creatures to turn into food pellets to feed their stock. Lars Tennson of the Norwegian Norwegian Fishermen's association complains that "the huge quantities of small fish caught by industrial trawlers is helping to strip fishing grounds of the small fish and of other species, including wild salmon, that depend on the feed fish"

Fish farms are also being blamed for increasing levels of nitrogen in the ocean. Over the last 2 years there have been 26 effluent leaks involving nitrogen-rich fish droppings. Naturally occurring algae feed on this and grow into large toxic blooms that kill most other marine life. Even legal chemicals used in farms, such a those used to combat the sea lice, can unbalance micro-organism populations, affecting the other organism that feed on them. Kevin Dunnon, director of FEO Scotland, has warned that "using inappropriate chemicals and medicines has the potential to do real environmental damage... We will prosecute if we find enough evidence"

In spite of the evidence that farming is harming fish populations, fish farmers are adamant that they are not responsible. Nick Jury insists that "algal blooms and the decline in fish stocks have occurred naturally for decades because of wide range of unrelated and more complex factors." Jury feels that fish farms are being made a scapegoat for lack of government control of fishing.

Overfishing is a major problem that affects salmon stocks and not just salmon. A combination of high trawler catches, net fishing at estuaries, sport fishing and poaching have all led to stocks of wild salmon diminishing. The UK government likes to thing that this problem has been recognized and that the roots of the problems have been attacked by laws passed by them. Fishermen, at sea and in estuaries, have been set quotas and many salmon rivers have been closed to fisherman. Poachers are more difficult to control but their effect is not as marked as that of the fishermen. Angus Kilrie of the NASF feels that the efforts have been wasted: "Legislation has merely scratched the surface", Not enough money has been forthcoming to compensate fishermen and the allowances have been set to high

The fate of the wild Atlantic salmon is anybody's guess. Farmers and governments seem unworried, environmentalist fear the worst. Wild Scottish salmon stocks this year have actually gone up this year which is heralded by the UK's fisheries department as a result of their policies. Paul Knight, Director of the Salmon and Trout fishing association has stated that he is "delighted with the upturn in numbers this year." He adds the warning warning though that "there are still significant threats to salmon stocks and that it is important not to take our eye off the ball". Statistics though can always be interpreted in different ways. All issues concerning the health of the wild north Atlantic salmon need to continue to be addressed in order to protect the viability of future runs

Vocabulary
- proliferate (v): sinh sôi, nảy nở, phát triển
    - proliferation (n): sự sinh sôi, sự tăng nhanh chóng về số lượng

- explode: (v) làm nổ, làm đập tan, làm tiêu tán
- angler: (n) người câu cá, người đánh bắt cá
- perilous: (adj) nguy hiểm, hiểm nghèo, hiểm họa
    - perilously (adv)
    - perilousness (n)
- hotly: (adv): sự sôi động, kịch liệt
- dispute (n) cuộc bàn cãi sự tranh cãi
    - dispute (v): tranh cãi bàn cãi
      dispute with (against) somebody: tranh luận với ai
      dispute on (about) a subject: tranh luận về chủ đề gì
- grave (n): mồ mả, sự chôn vùi, sự chết, thế giới bên kia
- threat (n): sự đe dọa, lời đe dọa, sự hăm dọa
     - threaten (v): đe dọa  
- aggressive (adj): hay gây hấn, hung hãn, xông xáo
    - aggressively (adv): xông xáo, tháo vát
- evolve (v) mở ra, suy luận ra
- involve: (v) gồm, bao gồm, liên quan đến, dính líu tới
- circumstances: hoàn cảnh, tình huống, trường hợp
- habitat (n): môi trường sống, nơi sống của cây cối động vật
   - habitant: người ở, người cư trú
- thrive: (v) thịnh vượng, phát đạt
- prey (n): con mồi, a bird of prey - chim săn mồi
    - be/fall prey to sth: làm mồi cho cái gì
    - prey on/upon somebody's mind: dày vò ai
- trawler: tàu đánh cá bằng lưới
- feed: sự ăn, sự cho ăn
- marine: t
- blame (man): sự khiển trách, lời trách móc