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Salmon at Bowker Creek

Salmon at Bowker Creek

By OB24
What would it take for salmon to return to Bowker Creek? Take a look at what is preventing salmon from living in Oak Bay, where they once flourished.

Entries


Why do We Want Salmon at Bowker Creek?
By OB24
If salmon were to return to Bowker Creek, they would not only help the creek to reach a climax community, they would increase Bower Creek's connection to the community. Having salmon would make more people interested in helping with the restoration and learning about Victoria's ecosystems.

Possible Solutions for Water Quality Issues
By OB24
Nitrates get into Bowker Creek through garden and road runoff containing plant fertilizers. As there are few nitrate free fertilizers, a way to reduce the nitrate levels in the creek would be to control the amount of fertilizers used near the creek. If this problem were to be fixed, there could be enough dissolved oxygen for salmon. 

Obstacles in Bowker Creek
By OB24
Could the salmon get through the tunnels at Bowker Creek? Most of the tunnels would be easy for the salmon to swim through; the only problem would be the sloped tunnel under Fireman's Park. The angle of the tunnel would prevent salmon from swimming up it. For salmon to swim through the creek, a small fish ladder must be put in this tunnel.

Water Quality Issues
1In 1 playlists
By OB24
There is too much nitrate and not enough dissolved oxygen for salmon. The abundance of nitrate contributes to the lack of D.O. One of the reasons for all the nitrate is probably fertilizers from road runoff and gardens, which is full of nitrate. If the nitrate levels could be decreased, the D.O. would increase, and maybe be able to support salmon.

Salmon’s Role in Bowker Creek
By OB24
The addition of salmon would have a large impact on the ecosystem. Although adult salmon don't eat while breeding, the babies would eat insects, plankton, and invertebrates. Animals like raccoons, herons, hawks, and eagles would eat the dead adult salmon. The salmon would create a more stable and diverse community in the creek.

Fish Ladders
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By OB24
For salmon to be able to swim through the tunnel under Fireman's Park, a fish ladder would have to be installed. The fish ladder that would be put in Bowker Creek would not be as complicated as the one in the video below, as this is just a short tunnel, not a dam. 

The Salmon Cycle
1In 1 playlists
By OB24
Salmon return to their birthplace to breed. The breeding pairs lay their eggs and die soon afterwards. Once the young salmon are old enough, they swim out to sea. After a few years they return to their first home and repeat the cycle. Here is a diagram of the salmon life cycle.

History of Bowker
1In 1 playlists
By OB24
Before Bowker was subject to urbanization, it supported Chum and Coho salmon. The salmon were a very important part of First Nations' culture, not only for food, but also for roles in their stories. It's a shame that most of the history of the creek has been lost and isn't known  anymore. The salmon could bring back the connection to the past.

Water Quality Chart
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By OB24
This is a chart that compares the water quality of Bowker Creek to the water quality necessary for salmon. As your can see in the chart, there is too much nitrate in the water and not enough dissolved oxygen necessary for salmon.

Restoration
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By OB24
It will take a lot of effort from the groups helping with the Bowker Creek restoration, such as the Greater Victoria Green Team, the CRD and Oak Bay High, to clean up the pollution to make Bowker suitable for salmon again. Hopefully, when Bowker Creek has been sufficiently restored, we will be able to reintroduce salmon to this urban ecosystem.

Pollution at Bowker Creek
By OB24
In Bowker Creek, there are many species that act as bioindicators, such as leeches, sticklebacks and aquatic worms. Bioindicators are organisms used to gauge the health of an ecosystem. The organisms found in the creek all have a high pollution tolerance, meaning the creek is polluted. If we want salmon to return, the pollution must be reduced.

Chum Salmon
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By OB24
The salmon in Bowker would probably be Chum salmon (Oncorhynchus keta), the most common species of salmon on the island. They have a 3-4 year lifespan and spawn in freshwater streams.  Chum are the most sensitive species of salmon, which will make it difficult for them to return to Bowker Creek, but aren't discriminating as to where they spawn.
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