Just before the turn of the 20th century, in the UK, the first attempts of Atlantic Salmon (Salmo salar) aquaculture began. Around that time, anglers found that releasing eggs of salmon into the water would increase their fishing yields. By the 1960’s sea cage aquaculture was experimented off the coast of Norway. Sea cage aquaculture proved to be successful and soon, many other countries began to raise Atlantic Salmon as well.

Fast forward to the present and we see in news and media that this heavily aquacultured species may pose more problems than its worth. Hybridization between Atlantic and Pacific Salmon, outcompetition of native species from escaped Atlantic Salmon, and dead zones beneath the large net pens are all issues that are being explored and researched. Are these salmon the main detriment to Pacific Northwest Systems? We will explore these problems and more, and we may even discover that some things we thought were facts may not be completely true…….

A long time ago, in a country far, far away…ATLANTIC SALMONEp.1 The Salmon Menace

Brief History of Atlantic Salmon Aquaculture• The aquaculture of Atlantic Salmon

originally started in the late 1800s-1900s as a means to increase returning wild salmon yields to fishermen(“Cultured Aquatic Species”2013).

• Eggs were fertilized and then released into riverine systems

• In the 1970s, the first sea cage aquaculture began off the shores of Norway(“Cultured Aquatic Species”2013)

• Presently, Atlantic Salmon are reared all over the world. In the U.S., Atlantic Salmon are raised in Maine and Washington.

• Around 20,000 tons ($130,000,000.00) of Atlantic Salmon are farmed in the U.S. every year(“Fishwatch”2012).

Wild Atlantic Salmon Health

• Atlantic salmon populations are now extinct in 42 U.S. rivers and are endangered in the remaining eight. These eight rivers – located in Maine – saw a combined total of just 72 salmon returning from the ocean in 2003(“Atlantic Salmon”2013).

• Habitat loss due to dams, past overfishing, and pollution are contributors to declining numbers of these salmon.

• Wild populations breed with escaped farm populations which leads to less genetic diversity

Threats of farming in the Pacific and Atlantic• In the early 2000’s there was quite a bit of public

concern regarding escaped Atlantic Salmon in the Pacific Northwest.• There is no evidence that Atlantic Salmon have

established populations in the Pacific Northwest even after effort to establish populations in the 80’s and 90’s(McKinnel, S 1997).• There is disputing research about salmon farming

causing sea louse blooms which may cause wild populations of salmon to decline or go extinct(Krkosec, 2007).• Dead zones are areas under cages that create low

oxygen and nutrient rich environments that cannot support life(Leahy, 2008).• Farmed Atlantic Salmon have low genetic diversity,

which is hurting wild populations of Atlantic and Pacific salmon.

Genetic Diversity

Farmed Atlantic Salmon have the greatest negative impacts on their own home range.Farmed Atlantic Salmon are very different from their wild conterparts.

Disease Outbreak

• As mentioned before, sea lice can possibly have detrimental effects on both wild and farmed fish.• Diseases outbreaks occur quite

a bit in farmed salmon but historically haven’t spread to wild salmon.• Salmon anemia is a new

exception to this rule(Dean,C.,&Nuwer,R, 2013).

Dead Zones• Still a threat but

not as much anymore.

• Moveable cages greatly help keep dead zones from occurring

• Pollution still a problem

Will Atlantic Salmon Farming Kill Pacific Salmon?

Maybe …Probably not

• Very rarely hybridize with pacific salmon

• Majority of fishes can’t compete with pacific salmon

Surprising Findings…

• Atlantic Salmon farming more detrimental to wild Atlantic Salmon than Pacific Northwest systems• Habitat loss, lack of genetic

diversity, overfishing by far the largest threat to Pacific Salmon

How do we restore Pacific fisheries?

Alaska could help us find an answer…

• Banned fish farming in 1989• Has a sustainable

fisheries (Bristol bay)• Still has problems with

aquacultured pacific salmon

• More than 20% of all salmon returning to spawning grounds are aquacultured• Low genetic diversity• Large numbers of fingerlings

released into systems breaches carrying capacity• Dams confuse fish and prolongs

migrations

Problems with aquaculture

Different ways to aquaculture Pacific Salmon

• New methods collect salmon from staging areas and help increase diversity• Lower number of raised

fish• Tear down dams (yeah,

right)

Other threats (and possible solutions)Problems

• Hydro-electric dams• Development• Pollution(Pebble Mine)

Solutions

• Tear down old dams/ more research into fish passages• Set aside systems as no-touch• Just say no to mines

•Atlantic Salmon may not impact Pacific Northwest Salmon as much as we thought•Human users must be

considered•People eat seafood

more than ever- aquaculture is still the best answer

Things to consider…

Solution?

A combination of research, public interest and participation, combined with making the necessary sacrifices and willingness to commit (restrictions on fishing, no development etc.) is what is required for all salmon populations to be able to recover.

Conclusion

FAO Fisheries & Aquaculture Salmo salar. (n.d.). FAO Fisheries & Aquaculture Salmo salar. Retrieved November 20, 2013, from http://www.fao.org/fishery/culturedspecies/Salmo_salar/en

FishWatch. (n.d.). NOAA. Retrieved November 19, 2013, from http://www.fishwatch.gov/seafood_profiles/species/salmon/species_pages/atlantic_salmon_farmed.htm

SeaWeb - Ocean Briefing Book. (n.d.). SeaWeb - Ocean Briefing Book. Retrieved November 21, 2013, from http://www.seaweb.org/resources/briefings/atsalmon.phpMcKinnell, S. (1997). Recent Events Concerning Atlantic Salmon Escapees In The Pacific. ICES Journal of Marine Science, 54(6), 1221-1225.

Krkosek, M., Ford, J. S., Morton, A., Lele, S., Myers, R. A., & Lewis, M. A. (2007). Declining Wild Salmon Populations In Relation To Parasites From Farm Salmon. Science, 318(5857), 1772-1775.

Leahy, S. (n.d.). BIODIVERSITY: The Real Price of Farmed Salmon>. BIODIVERSITY: The Real Price of Farmed Salmon>. Retrieved November 21, 2013, from http://ipsnorthamerica.net/print.php?idnews=1833Dean, C., & Nuwer, R. (n.d.). Salmon-Killing Virus Seen for First Time in the Wild on the Pacific Coast. www.nytimes.com. Retrieved November 21, 2013, from http://www.nytimes.com/2011/10/18/science/18salmon.html?_r=0Gable, D. (n.d.). ENN: Environmental News Network -- Know Your Environment. : Hatchery-Raised Salmon Threatening Wild Salmon in the Pacific Northwest. Retrieved November 21, 2013, from http://www.enn.com/top_stories/article/41956