Saturday , June 10 2023

Researchers on the state of & # 39; B.C. Salmon in & # 39; sheet & # 39; hot water – Terrace Standard


Anomaly or the new norm, researchers are carefully monitor the bubbles persistent warm water in the Pacific Ocean east and what they mean for salmon.

In recent months, line & # 39; high pressure developed on the coastal area of ​​& # 39; B.C. led to an extended warm summer. The storm season was late, and the water is two to three degrees warmer.

Richard Dewey, associate director of science at & # 39; Ocnet Networks Canada, and the University & # 39; Victoria, carefully follow the area & # 39; about 2,000 kilometers she fell & # 39; b & # 39; unsatisfactory way which made its first appearance in autumn 2013 and has become much more noticeable in the 2014 spring – when researchers left the term "blob ".

"That woke us up event for what is happening here. The atmosphere, the weather and the current jet together and get weaker winds on golf and so we do not nħalltux cold water things stay warm, "said Dewey.

Now pay attention. Until 2017, the oċeanografi started seeing the hot mass is wasted in depth, but this year is back in the North Pacific and the Bering Sea.

"Maybe this is the trend. Perhaps this is how climate change will be reflected in our barrel, but we would rather not know that & # 39; now," said Dewey.

Ocean Networks Canada has instruments along the bottom and near the shore & # 39; ocean. Do not take the blob of 2014 on their sensor to a few months, so the researchers are keeping close to the satellite data and sea surface temperature charts for Gulf -Alaska.

Impacts on salmon

The ocean warming is affecting freshwater temperatures also.

Sue Grant is leading the State of Salmon Fisheries and the Canadian Ocean (DFO). Its role is to integrate what we know about salmon and their ecosystems. The oċeanografi and freshwater researchers are seeing co-relationship between the blob and heating rivers and streams.

"The Blob itself is an oceanographic phenomenon but is caused by coupling with & # 39; the atmosphere and also has repercussions in fresh water," said Grant.

Salmon are anadromous, with life stages of freshwater and marine, and experiencing warmer temperatures in both habitats. The administration said the effects of the hot blob of 2014 and 2015 vary across the salmon stocks in & # 39; BC. and the territory & # 39; Yukon.

"Reactions are mixed, although some of our southern stocks and some of our north were not doing so well this year. We've seen lower average survival of salmon stocks in valley & # 39; Fraser the last year throughout the different species and we see the survival below the average survival again & # 39 others; this year in Fraser. There are other examples in the north, "she said.

The grant using marathon analogy to describe what temperatures & # 39; 3-5 degrees Celsius on the season doing salmon.

Would have run a marathon in & # 39; 50 Celsius degree she can not stand & # 39; life as 50-60 degrees Celsius is outside the optimum range & # 39; its temperature. Salmon also range & # 39; optimum temperature as well, and when trying to migrate during the summer, can & # 39; have a negative effect on their migration.

The warmer water temperatures of the media also impacting the level & # 39; nutrients.

When the ecosystem changed in 2014-2015, the surface layer of the Gulf & # 39; Alaska was weaker in nutrients. Networks & # 39; Canada Ocean saw that species & # 39; cold water environment requiring b & # 39; many nutrients were not prevalent, while the species & # 39; hot water that can adapt to conditions & # 39; low nutrient tended to dominate.

"When there are salmon in the Gulf and along the coast to eat under those conditions returned in 2016-17, slightly smaller than usual," said Dewey.

"The numbers I have seen say that these hot conditions can lead to sizes & # 39; smaller fish so that also has some impact."

Both Grant and Dewey say they are paying attention, but it is too early to make projections and the hot blob 2018 means salmon.

They may however take the data from the last few years – salmon answers heating at & # 39; fresh water and marine ecosystems – and whether there model and x & # 39; can & # 39; mean for the future of salmon stocks.

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