Saturday, May 22, 2010

Salmonids

There are five species of Pacific salmon that die after spawning; Chinook, Chum, Coho, Sockeye, and Pink. Salmon return to their natal streams and rivers each year. Salmon travel thousands of miles and spend one to five years feeding in the ocean before returning to their birth streams. Spawning females dig out a gravel nests, called a redd. The males then fertilizes the eggs and the female protects the redd for one to two weeks. Alveins hatch and mature into fry, developing vertical bars for camouflage, called parr marks. After a period of feeding fry migrate downstream towards the ocean and grow into smolts adapting to their marine environment.

Chinook
Oncorhynchus tshawytscha
Spring, Salmon, King, Blackmouth,
Quinnat, Chub, Tyee (14+kg)
Chinooks have a greenish-blue dark back with
long black spots, a red hue develops around
the fins and belly, male teeth are enlarged and
they have a hooked snout. Tyee reach 1.5 m
and 58 kg, average 90 cm and14 kg. Spawning
peak May to June and August to September.

Chum
O. keta
Dog Salmon
Females are a metallic
blue, males have a
checkerboard colouration,
a dark horizontal stripe, and
canine-like teeth. Average
from 4.5 to 12 kg. Spawning
peak month October.

Coho
O. kisutch
Silver Salmon
Spawning males are red on
their sides, and a bright green
on the back and head areas, with a
darker colouration on the belly, spots
on upper tail fin lobe. They also develop
a hooked jaw with sharp teeth. Females
develop a lesser-hooked snout. Coho
reach 1 m and weigh up to 14 kg, they
average between 3 to kg. Spawning
peak July to August.

Sockeye
O. nerka
Kokanee, Red Salmon,
Blueback Salmon
Varying shades of red resulting
in a brilliant scarlet fish with a
green head. Grow to 83 cm
and weigh up to 7 kg. Spawning
peak month August.

Pink
O. gorbuscha
Humpies
Pale grey, males
develop a hump.
Get up to 76 cm
and to 5.5 kg,
average 1.5 to 2.5 kg.
Spawning peak month
October.

Threats
On top of natural dangers from predators dangers to salmon from human activities include poor farming and forest practices, pollution, destruction of coastal wetlands and estuaries. The territory of British Columbia salmon has been decimated for decades by industrial clearcut logging. Roots of trees anchor steep slopes. Logging increases the chances of landslides filling vital spawning grounds with mud, debris, and boulders. Shade from trees is lost increasing water temperatures. Other threats include overfishing, urbanization, hydroelectric dams, and fish farms.

Actions
Salmon play an important role sustaining forest ecology. Spawners bring vital nutrients from the ocean into the forest. Carcasses are dispersed by bears and eagles providing the trees with fertilizer; nitrogen, phosphorus, and carbon. Salmon feed the rivers helping the survival of young salmon. Farmed salmon does not replicate this vital role and is detrimental to wild stocks. Dangers from fish farms include disease, pollution (including contaminating shellfish), predation on young wild salmon, and escapement (Atlantic salmon compete for food and habitat with wild stocks). Conservation actions include cleaning up salmon streams (ensuring clean and safe flowing environments), recycling, using biodegradable/organic products, and choosing wild salmon over farmed.

Tuesday, May 04, 2010

Rally for Wild Salmon

Parliament Buildings, May 8th @ 4pm

fry

Threats:

Sea Lice - Salmon aquaculture is prohibited in Alaska for economic and environmental reasons. Built along the shoreline, farmed salmon are particularly susceptible to diseases and parasites, such as sea lice, that can be lethal to fish. Sea lice, viruses and other pathogens have contaminated wild salmon stocks swimming nearby, many young wild salmon become infected and do not survive as a result.

Escapes - Atlantic salmon are an aggressive species that are not indigenous to the Pacific Northwest. Atlantic salmon have been found in dozens of rivers and lakes throughout British Columbia and Alaska. There is only one species of Atlantic salmon (Salmo salar) on the east coast whereas there are several species of salmon on the west coast. Atlantic salmon are strong competitors and have historically wiped out other east coast salmon pieces.

PCBs - Farmed fish is fattier and therefore can store more PCBs and other contaminants at levels of up to 10 times higher in farmed salmon. Polychlorinated biphenyls PCBs are mixtures of up to 209 individual chlorinated compounds. There are no known natural sources of PCBs, they are either oily liquids or solids, that have been used as coolants and lubricants in transformers, capacitors, and other electrical equipment because they don't burn easily and are good insulators. The manufacture of PCBs was stopped in the U.S. in 1977 because of evidence that they build up in the environment (bioaccumulation; concentration increase at each tropic level) and can cause serious health effects. PCBs persist in the environment, fish absorb them from contaminated sediments and their food. Government regulations allow much higher levels of these contaminants in farmed salmon than are allowed in wild salmon.

Oil spill in Gulf Proves the Need for an Oil Free Coast in British Columbia

BC First Nations and environmental groups are calling on the federal government to implement a permanent ban on oil and gas development and tanker traffic on the North Coast of British Columbia, in light of the failed attempts to clean up the oil that is spewing from a sunken rig in the Gulf of Mexico. The Living Oceans Society, with an office in Vancouver, in a statement released on April 29, commented on the Gulf of Mexico oil spill and how it may impact BC oil exploration. Despite having the required safety mechanism on the Deepwater Horizon oil rig, an explosion occurred, the technology to stop the oil from spilling in to the ocean failed, and the weather delayed the clean up efforts. “Over 30 years ago the federal and provincial governments prohibited oil and gas development and oil tankers on this coast because they knew that the threat of an oil spill was too great, a clean up too hard, and our ocean too valuable.” says Jennifer Lash. Executive Director of Living Oceans Society. “Now the Enbridge Gateway project is threatening to bring over 225 oil tankers onto our coast every year putting at risk our whales, birds, fish, bears, and coastline.” In March 2010, 10 First Nations from the North and Central Coast and Haida Gwaii banned oil tankers from their traditional territories. “The First Nations governments have taken action to protect the ocean that supports our communities,” says Art Sterritt, Executive Director of the Coastal First Nations. “Now we would like to see the same leadership from the federal government.” The groups are pointing to the challenges of cleaning up the spill in the Gulf of Mexico as a grim reminder that failed technology and bad weather can make the impossible even harder. “They thought they could contain the spill off the coast of Louisiana but every day they appear to be having more challenges,” says Nikki Skuce, Senior Energy Campaigner of Forest Ethics. “Apparently oil rigs are ‘considerably safer for the environment than tankers’ – which isn’t much reassurance as we’re asked to risk our coast for Enbridge’s profits. An oil spill on our North Coast would be an imaginable tragedy.” Metro Vancouver is also not immune to oil spills. In 2007, a major oil spill forced residents of a Burnaby neighbourhood from about 50 homes, and raised serious environmental concerns. In 2009, a cruise ship admitted responsibility for an oil spill on the waters of Vancouver harbour near Canada Place.

Link