Download
1 / 19
240 likes | 558 Vues
Salmon. Maia Janz Geography 12 Mrs. Hayter. What are Salmon?. Salmon are anadromous fish which means they breed and spawn in freshwater but spend most of their adult lives in saltwater
E N D
Salmon Maia Janz Geography 12 Mrs. Hayter
What are Salmon? • Salmon are anadromous fish which means they breed and spawn in freshwater but spend most of their adult lives in saltwater • There are 5 species of Salmon in our Pacific waters: Chinook or King Salmon, Coho Salmon, Sockeye Salmon, Pink Salmon and Chum Salmon
Why are Salmon important in BC? • Salmon play a vital role in the ecosystems of BC. They are food for animals who reside around the rivers and oceans they live in, and when they die they provide the surrounding areas with essential nutrients from their bodies as they decompose. • Another reason for why Salmon are important in BC is that they generate a large revenue in the fishing industry • Salmon are also very important in the culture and history of the aboriginal people
Problems involving Salmon • BC is home to the best salmon fishing in the world! But due to the extensive fishing of salmon, their stocks in BC have been declining at an alarming rate since the late 1980’s • Climate change has also contributed to the decrease of Salmon in our rivers • Pollution and damming of rivers is another cause in the depletion of Salmon stocks
Fishing • Salmon are increasingly being over fished in our oceans and rivers • Is recent years over 50% of adult salmon were killed by fisherman in our region • As our world population grows, the need for food also grows and this is not good news for salmon • Fishing of salmon is not only an industry, it is a sport. People come from all over the world to fish our salmon and there are hundreds of fishing lodges in BC. Sport fishing does not account for much of the depletion of the species but it does contribute • The last salmon spawning season had the lowest recorded return – 1 million of 10 million salmon returned to the ocean
Not only are salmon fished in open water, due to their high demand, fish farms are becoming increasingly popular Fish farming is the practice of raising salmon in cages in embayment at sea, or in ponds on land Fish farming has helped the decreasing salmon population because it uses chemicals which help to prevent diseases and the build-up of organic sludge in fish-cages There are many people against fish farming due to the need of chemical use Fish Farming
Fishing • A good example of an over fishing tragedy was the rapid decline and near disappearance of the Atlantic Cod fishing industry • Here fish have been caught in such high quantity that there is no way they can spawn back to normal numbers • If moderation in fishing was practiced here fishing would still be a way of livelihood in the Atlantic regions • Regulations need to be put on our fishing industry in the Pacific before a devastation like this happens here
Climate Change • Increase of heating and cooling in river temperatures and more regular warm temperatures will most likely change the Salmon’s habits for these reasons: • Young Salmon are more likely to die in warmer water • Salmon may not grow to their full size because of an increased competition for food and a faster metabolic rate • Water temperatures above 15ºC stresses out fish which can lead to them being more susceptible to disease (this same stress may lead the fish’s production of sperm and egg to decrease) • Energy levels may become lower which would decrease spawning success because smaller weaker fish may not be able to reach the spawning grounds
Climate Change • Climate change will also alter salmon’s habits for these reasons: • As the temperature increases the fish will want to find colder more northern waters which will increase their migrating distances • Variable river flows with lower minimum water levels will be more common which may harm salmon trying to swim upstream for spawning, which would decrease future generations of salmon
Climate Change • Marine environments are considered to be resilient (flexible) ecosystems which means they can adapt to changing conditions, but not at such a fast pace!
Pollution • A lot of pollution makes it into our oceans and rivers from mining, forestry and urbanization • Pollution accounts for many salmon deaths each year
Damming • Hydroelectric power is a very large industry in BC even though it causes a lot of damage to the salmon. These large scale dams that are being built on rivers in BC obstruct the historic natural routes of the salmon which lead them to their spawning grounds. • Many salmon exhaust themselves to death trying to jump these dams • To help this problem, communities surrounding these dams have put in requests to build salmon “ladders” beside these big dams so the salmon safely proceed through the dams upstream to their spawning grounds
What are we doing to help? • Fishery biologists are attempting to stem the salmon declines by enhancing wild stocks. An example of this is releasing large numbers of captive-raised, young fish. • Fisherman and conservationists are uniting together to save the salmon population
How can you help? • If you enjoy eating fish or using products that contain fish oils or other nutrients, integrate other fish than salmon into your diet • Clean up streams in your area • Don’t dump chemicals into drains in your home, at school, or outside in your community (antifreeze/bleach) • If you own a pool, don’t drain it! Dispose of the chlorine-filled water elsewhere • Encourage your government to regulate fishing in our oceans, lakes and rivers • Raise awareness!! People won’t know about the Salmon if we don’t tell them!
Our salmon ecosystem is really one of the last great fish habitats in the world! So we should all do what we can to conserve it – before it’s too late!
Bibliography • http://cciarnbc.ubc.ca/key_salmon.php • http://science.jrank.org/pages/5942/Salmon-Water-pollution-fishing-fish-farming.html • http://www.salmonnation.com/ • http://www.vanaqua.org/salmontales/english/learningcentre/humanimpact.php • http://en.wikipedia.org/wiki/Salmon • http://wc-zope.emergence.com:8080/WildernessCommittee_Org/campaigns/wildpacific/salmon_farms/reports/Vol21No05 • http://www.psc.org/ • Images: http://www.google.ca
