Hotter water linked to poor sockeye returns

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      A UBC fisheries expert's warning from the 1990s now sounds prophetic with this summer's poor returns of Fraser River sockeye. UBC professor Scott Hinch predicted 15 years ago that warming sea-surface temperatures due to climate change would result in smaller and less abundant sockeye.

      “It was some of the first work ever of that kind, and nobody's really followed up,” Hinch told the Georgia Straight.

      More than 80 percent of the 10.6 million fish predicted by Fisheries and Oceans Canada are nowhere to be found in the Fraser, raising doubts about the future of this iconic species.

      In a paper published in the Canadian Journal of Fisheries and Aquatic Sciences in 1995, Hinch and his colleagues stated that warm sea temperatures could impair production of plankton—organisms that start the food chain in the ocean—triggering a series of consequences.

      “Assuming that growth rate is related to survivorship in the ocean, and it should be, then, yeah, it suggested that fewer adults may come back and they would be smaller,” Hinch said. “And it also carried the logic further out of the ocean into the river and said that smaller adults, those with lower energy, should have a more difficult time completing the river migration.”

      Some 3.3 million Fraser sockeye reached their spawning grounds in 2005. According to the Pacific Salmon Commission, surveys in the Quesnel and Chilko tributaries indicated that about 130 million sockeye smolts moved out to the sea in 2007 for their two-year ocean migration.

      What happened to these juveniles?

      Jeff Grout, FOC's salmon resource manager, said he suspects that the fish didn't survive at expected rates. He rejected any suggestion that fish farms are responsible for poor returns.

      “We have some information for juveniles that out-migrate from one of our big lakes in the Interior, the Chilko run. We did have a lot of juveniles—well above average—leave that system in fairly good size, which usually bodes well for their survival,” Grout told the Straight earlier this month. “So”¦we're thinking that marine survival is likely a factor in the poor returns we're seeing—especially in that we're seeing poor returns across all of these different lake systems.”

      Hinch said that in the mid-1990s, coastal and northeast Pacific Ocean temperatures increased by half a degree and one degree Celsius, respectively, compared to the 1960s and 1970s. “So we're expecting, as climates continue to warm, another degree or two warmer in the next several decades,” he added.

      River temperature is as important as sea-surface temperatures for sockeye, according to another paper coauthored by Hinch that was recently accepted by the Canadian Journal of Fisheries and Aquatic Sciences. It noted that about 1.3 million adult sockeye entered the Fraser River in 2004 but didn't reach their spawning grounds. The paper stated that the record high temperatures in 2004 were a “significant factor” behind the 57-percent spawning mortality.

      Comments

      11 Comments

      Skeena Fisherman

      Aug 27, 2009 at 9:20am

      Youve got to be kidding. Ocean temperatures have risen for all of the north Pacific and yet there is no major loss of sockeye or other species returning to the Skeena, Nass or Alaskan rivers. They all feed and live in the warmer waters of the same ocean. The only real factor that is different is the fish farm gauntlet that these juveniles have to run in order to get to their feeding grounds. The professor is just trying to link this loss in the Fraser to some theory he had fifteen years ago and now the decline is so great in an extremely hot year on the Pacific coast he wants to tie the two together.
      Alexandra Morton predicted two years ago that this run would suffer tremendous loss due to sea lice infestation and for Hinch to ignore that is just ludicrous. If the warmer water affects the large salmon then the lake and river temperatures would have done the juvenile salmon in and that is not the case. There were strong survival rates of these smolts leaving the river two years ago. If the ocean temperature is to blame why have other countries (Russia. Alaska) and other areas not suffered the same losses? The answer is simple:Fish farms! You can't ignore that fact. You may not be able to do something about the climate but you sure as hell can change the way fish farms do business on our coast. Try closing them down for 4 years and see what happens to the returns. I'll guarantee they will be stronger than they are right now.

      Its the water, stupid!

      Aug 27, 2009 at 2:00pm

      Low salmon pops in Alaska, Oregon and California regions - and they don't have fish farms. Geez, get over it anybody who thinks that BC fish farms are a significant cause of low BC salmon numbers.

      Fishing for salmon is like hunting and gathering - thing of the past. Fish farms are here to stay - and the way of the future - better jobs, better safety and fewer months on pogey.

      Of course its the farms!!

      Aug 27, 2009 at 8:37pm

      Low salmon pops in Alaska? What is this guy talking about.!! Alaska has one of the healthiest salmon runs in the world because they banned fish farms!!Salmon farms are not farms at all. They are giant conveyer belts moving fish protein from the Southern Oceans to the rich North and are a terrible and disgusting blight on the environmental landscape.

      Laurence Gough

      Aug 27, 2009 at 9:55pm

      I agree with Skeena fisherman. The Campbell government has an agenda - increased aquaculture - and has never been interested in science. Sea lice are killing our salmon. How much longer until our resident (Georgia Strait) Orcas have disappeared? DFO is a bad joke. Gutless political lapdogs.

      Tessa

      Aug 27, 2009 at 11:13pm

      Of course ocean temperatures have an impact, this is well known. Fish can't survive when the water gets too hot. But fish farms shouldn't be dismissed, either. It's not just a single variable that affects the surviveability of a species in such a complex ecosystem.

      Skeena Fisherman

      Aug 28, 2009 at 8:25am

      It's the water, signed by stupid. We have had the hottest summer on record in the Skeena and Nass watersheds and the fish seem to be doing just fine. The ocean waters are warmer in the north too. The sockeye travel north to feed. Both fish farms and warm water may play a part but fish farms is the main reason for the decline of wild salmon around the world, proven over and over again. In Scotland, Ireland and Norway the farms have been responsible for wiping out huge numbers of wild fish.
      The only reason you would blame warm water would be because you are a fish farmer or are employed by them If warm water is to blame then all the salmon species including steelhead, which like cooler water temps, and yet we are having one of the biggest returns of these fish in years. Pinks are doing very well here also, so get you head out of you backside and come to grips with the real world. Fish farms are fatal to fish. Period.

      Yes, low returns in Alaska and Skeena

      Aug 28, 2009 at 8:41am

      Is Skeena fisherman really from that area? If so, how does she/he not now that the Skeena watershed had less than 50% of expected sockeye return (google it!)? And, with the exception of Bristol Bay, Alaska has had one of the worst sockeye returns this year. Chinook have also been missing in Alaska.

      In contrast, salmon that come from rivers that swim the same path of Fraser sockeye ( Nanaimo, Heydon, Philips, Campbell, Adam, Eve, Kakweikan, Quatse to name just a few) have had exceptional and record returns of pinks and Chinook and sockeye (google it!).

      In fact, the Campbell River (in the heart of salmon farming) is having its BEST return of salmon in recorded history!

      I agree with Tessa, there are many factors to look at and salmon farms are just one of them, but way, way down on the list in my opinion.

      I would suggest that "Skeena fisherman" simply has a vested interested in repeated "untruths" about salmon farming (and wild salmon returns) because they compete directly in his/her market.

      Skeena Fisherman

      Aug 28, 2009 at 7:53pm

      Just got back from fishing the Skeena just outside Terrace. I can do this because I am retired. The interest I have is to protect wild salmon. I am a member of Friends of Wild Salmon which was instrumental in keeping fish farms out of the mouth of the Skeena River. I caught 2 steelhead, 2 coho, 3 pinks and 1 sockeye. This in two hours of fishing. Great to have that kind of resource 25 minutes from home. I will do anything to keep it that way.
      Of course there are many factors to look at but if you think salmon farms aren't instrumental then you are delusional.
      Which salmon are returning in large numbers to the Campbell? Are they pinks? There are huge number of pinks in a lot of rivers because of the odd numbered year factor and a lack of commercial fishing along the coast.
      If warm water is the problem then why are these numbers high? Is the water different along Vancouver Island? Why do countries like Norway Scotland and Ireland point to fish farms as the reason for their wild salmon declines? Probably the water temperature as far as you are concerned but this has been going on for years in those countries and only the fish farmers deny the effect of aquaculture on the decline and some of them are saying fish farms should not be anywhere near salmon spawning rivers. Why are we so reluctant to move ours or put the Atlantic salmon in closed containers? The fish farm lobbyists have Gordon in their pocket and they are not about to let him go.
      Think of our greatest natural resource and stop feeding us low quality fish that contain chemicals, dyes, antibiotics and insecticides. Only farmed fish come with a warning to pregnant women and nursing mothers. How can this be the the way of the future? Surely, we know better than that. At least most British Columbians are smart enough not to buy into this malarky. The USA is soon going to ban any fish that has been treated with SLICE like they do in BC. Then the market will dry up and fish farms with be a thing of the past. Soon people will be unemployed and on pogey.
      Check out the Skeena Tyee Test fishery result and you will see that the 2005 numbers for sockeye were extremely low due to commercial over fishing thanks to a screw up by the DFO. The progeny from that disaster has rebounded to a 50% increase and will continue to improve if the Feds don't get carried away again. Check out the numbers for other species in the Skeena and you'll see that we are in very good shape compared to the Fraser.
      No mention of Sockeye in the Campbell, just pinks.
      Also check out his website:http://www.farmedanddangerous.org/news/177 and how about this for the Nanaimo: Brian Banks, co-manager at the Nanaimo River Fish Hatchery, said he also hasn't heard of an inordinate number of dead salmon at the bottom of the river, where it meets the strait. The water in the river may be warmer than usual for this time of year but not enough to kill salmon, Banks said.
      What is your interest in fish farms? Let's hear who or what your are.

      shepsil

      Aug 28, 2009 at 10:31pm

      Hey Skeena Fisherman, the commenter (Troll) that is replying to your comments won't ever print his name. He/She more than likely works for the Public Affairs Bureau (PAB has a budget of apparently over $40 million to spin the media Campbell's way) and he/she leaves little hints as to his/her contradictory comments thru-out this site.

      The most effective way to combat these monsters is to continue blogging and countering these trolls lies. Educate the public so they truly know what is going on and they won't vote for the Liberals or Campbell again.

      Check out my first comment on Suzuki's sockeye story here on the Straight and the links to understand how crucial commenters like you are going to be in this battle to save our province.

      Keep up the good work.

      Skeena Fisherman

      Aug 29, 2009 at 7:13pm

      Thanks