WARM WATER BACTERIA RESPONSIBLE FOR KILLING HUNDREDS OF SOCKEYE SALMON IN OSOYOOS LAKE

By on August 29, 2012
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Hundreds of dead sockeye salmon were washing up on the shores of Osoyoos Lake last week, many of them near Haynes Point Provincial Park. American fish and wildlife biologist Bob Rogers visited Osoyoos last Wednesday and confirmed the salmon died from a common warm water bacteria called Columnaris disease. Photo by Mathew White.

The combination of massive amounts of sockeye salmon travelling thousands of miles, the warm water that makes Osoyoos Lake the warmest lake in the country and a lack of oxygen all played a significant role in hundreds of fish dying and washing up on the shores of Osoyoos Lake early last week.
Robert Rogers, a fish and wildlife expert with the Washington Department of Fish and Wildlife, made the trip from Omak to Osoyoos last Wednesday after numerous reports were forwarded about dozens of dead fish washing up near Haynes Point Provincial Park.
Rogers said the fish died from Columnaris disease, a very common cold and warm-water fish pathogen that affect fish stocks worldwide.
“Some species are more susceptible than others. Unfortunately, sockeye salmon are very susceptible to this particular pathogen,” said Rogers. “It’s not uncommon when you get very warm water like we have here (Osoyoos Lake) and the gathering of an enormous amount of fish in one area.”
Not only does Columnaris bacteria breed and grow in warm water, but it also leads to the elimination of dissolved oxygen at lower depths as the salmon try and swim deeper to access colder water, he said.
“We had a large number of perch dying and washing up on shore of Osoyoos Lake a couple of years ago and it was from exactly the same thing,” said Rogers. “When you have the combination of a tremendous amount of fish accessing the same area and warm water, this bacteria tends to breed quickly and some of the fish simply aren’t going to make it.”
Rogers said estimates that 300,000 sockeye salmon entered Osoyoos Lake since the end of July are accurate.
With this amount of fish coming into a lake with the warmest temperatures in the country, there is going to be natural selection and a small percentage of fish are going to die, he said.
There is no threat whatsoever to human health relating to these dead fish, he said.
“It’s not in any way, shape or form a risk to human health, except for the fact it can become quite odiferous with any significant amount of fish dying,” he said.
After studying fish and fish habitat for more than three decades, Rogers said a small number of salmon are going to die during the annual run into Osoyoos Lake, but this year’s numbers might be higher than usual because it has been so hot throughout the months of July and August.
Osoyoos Mayor Stu Wells said he received about a half-dozen phone calls from worried citizens last Monday and Tuesday after dozens of dead sockeye salmon were reported dead and washing up along different shores in town, with the vast majority of dead salmon being spotted near the shores of Haynes Point Provincial Park.
When people realize that more than 300,000 salmon made their way into Osoyoos Lake over the past several weeks, most understand a small percentage are going to be killed, he said.
“Not all of the fish are going to make it to the spawning beds,” he said. “The reality is salmon don’t do well in warm water as they came from the cold waters of the Pacific Ocean and travel up the Columbia River near Portland, Oregon and they have a very long and difficult trip before they make it here to Osoyoos Lake.
“As everyone knows, we have a very warm lake and salmon just don’t do well in warm water. When the water temperature is over 21 degrees, a lot of them are being stressed and some of them die. It’s just the way it is.”
Because there are so many salmon and they travel so far over an extended period of time, it’s actually encouraging to know more than 99 per cent of the fish survive, said Wells.
“The CBC had a report about the dead fish and it was heartening to know there wasn’t a single comment looking to blame anyone,” he said. “The good news is the annual salmon run is back in record numbers and most of the fish are surviving and doing quite well when you consider everything.”
Bryan Holgate, a member of the Osoyoos Lake Water Quality Society, which is made up of a group of 15 volunteers who head out once a week to test water quality on the lake, said his group volunteered to pick up some of the dead fish that washed ashore.
The group went out on Sunday and helped collect more than 120 fish weighing almost 500 pounds, said Holgate.
“We had so many fish, we didn’t know what to do with them,” he said. “We could have kept going all day.”
A Town of Osoyoos half-ton truck was used to haul the dead fish to the local landfill Monday morning.
Richard Varty, park  manager at Haynes Point Provincial Park, estimated he and parks staff picked up over 800 dead fish between Aug. 21-25.
“We picked up 400 fish the first day on Tuesday and between 150 and 200 per day on Wednesday and Thursday, but we only had about 40 on Friday because it looks like the salmon run is almost done,” he said.
“We had a lot of complaints from the campers about the smell and as park manager, I took it upon myself to try and clean up as many fish as we possibly could.
“We spent a good four or five hours a day for those three days cleaning up the mess. The good news is it looks like the worst is over, at least for this year.”

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3 Comments

  1. David Heitsman

    August 29, 2012 at 2:44 pm

    “odiferous”, thats a polite word for it.

  2. Mark

    September 3, 2012 at 4:45 pm

    Warm water? This is what you contribute to the death of 1000’s of Salmon? Are you for real???
    We had a late spring, water levels were high, temperatures were below normal.
    Usually we have the temperatures that we had in July in May. In other words,the lake on a normal seasonal year, should have been much warmer.
    Correct me if I am wrong, which I almost always am as far as my wife is concerned, but don’t all those boats leak a little oil or gas? All the years of boat traffic, allowing sewage and waste into the water have no long term bearing on the oxygen levels in the lake huh? I think the Rainbow Trout,if there are any left will be the next to die out and then we will be left with carp head soup.
    Death of our natural resources is a common thing for the sake of tourism as is neglecting the issues of homelessness and starvation among our communities.
    To think that a beautiful lake like Osoyoos lake is being sacrificed as are the middle class working people for the sake of profit, just makes my stomach turn.
    Just for you people that don’t know what that big red machine is that looks like a dredger…
    This machine chews up all the natural habitat for fish just so that the tourists don’t feel any weeds on them while they are abusing the lake.
    The weeds that come up on shore are considered a noxious weed and are expected to be double bagged and taken to the landfill.
    Since when is a natural habitat for fish considered noxious?
    Only since the Osoyoos council decided that tourism was more important then our natural resources?
    God forbid that a tourist wipe out on his knee board and feel weeds on his hands.
    I must admit that I asked council to put portable bathrooms along Lakeshore Drive and finally got my wish after I moved away from Osoyoos.
    This project started well after I asked for it and was built in a spot,once again, for tourists sake.
    To this day I am not sure if it has been completed.
    I watched while I was still living there and after 4 months , it had still not been completed.
    Needless to say, I had to relieve myself in other areas. Where I had originally asked for a relieving station….
    As far as council is concerned… CJ Rhodes makes a perfect puppet and should join the CIA.

  3. Jonas

    October 25, 2012 at 11:26 am

    To Mark..your comment re concern for the lake…shared by many…made on Sept.3,2012@ 4:45 pm….
    What say you about DFO giving a licence for an Aquaculture Facility on Rd.17, south of Oliver, adjacent to the river, being allowed to discharge their ‘clean’effluent directly in to the river…
    On paper regulations will be adhered to….but nature is a mother, and it is the ‘what ifs that worry us.
    All the work done for Lake, river and salmon….and this will be done not under permit, which would allow for public input, but a registration application, under land based fin-fish regulations..section 8, waste management……Rd.17 is not too far north of Osoyoos , and in our opinion why would anyone want to put all the combined efforts at risk?

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