The Latest Squawk is:

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  • Gerrard rainbow trout spawners 2014

 

This year, spawners started arriving at Gerrard on April 19 and the last one left by May 23.

The peak count was 711 spawning rainbow on May 6, which is the 5th highest in the 50 year record (see graph showing peak daily counts from 1961 – 2014). Gerrard rainbow trout numbers, growth, and condition are adjusting to their kokanee prey supply.

 

 

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  •  

  • Meadow Creek kokanee fry

 

As of last Wednesday night we estimate 6.4 million kokanee fry have emigrated from the spawning channel and headed downstream to the North Arm of Kootenay Lake. The fry emigration continues and this number is climbing nightly, for the time being. These millions of kokanee fry will be providing the food for Gerrard rainbow trout and bull trout in the main body of Kootenay Lake for the next 3 to 4 years, when the uneaten kokanee survivors will return to spawn at Meadow Creek in 2017 and perhaps some maturing one year later in 2018. Of course, every cohort of kokanee each year supports not only the larger predator sport fish, but some angling and many other organisms that rely on kokanee from sculpins to osprey to Grizzly bear.

 

 

  • IHN virus

 

As you may know, we discovered IHN virus last fall in spawning kokanee around Kootenay Lake: Lardeau River, Meadow Creek, and Redfish Creek. This virus has not been observed before in Kootenay Lake, and is a risk to spawners, to developing juvenile kokanee, and can also infect other fish species.

 

So far, however, the news is pretty good:

  • We rinsed the channels with additional flow last year, and removed kokanee carcasses, in order to reduce virus presence around the developing kokanee embryos. Spawning appeared to proceed successfully, with a potential 20 million eggs in Meadow Creek spawning channel last fall.

  • This spring, egg to fry survival at Meadow is approaching normal percentages suggesteing limited or even no virus impact there.

  • All fry we have sent away to test for IHN virus this spring, have turned out negative: they are not infected with IHN virus.

  • As well, we sampled over twenty mature Gerrard rainbows this spring, and they too were all negative for IHN virus.

  • This summer we will be drying the channels around Kootenay Lake to kill as much residual virus as possible.

 

  • Kootenay Lake burbot recovery

 

  • There is an international team working on burbot recovery for Kootenay Lake and the Kootenay/Kootenai R. and among several important research programs is a conservation stocking initiative:

  • Using Moyie Lake burbot as the brood source for eggs, the team has stocked from 100,000 to 400,000 burbot larvae in Kootenay Lake in each of 2012 and 2013, at numerous sites from Boswell to Kaslo. The survival rate of these larvae will be very low, however some may survive to recolonize and spawn.

  • As well, older sonic tagged burbot (1-3 years old) have been released in the Kootenay/Kootenai R. upstream (south) of the Goat River confluence from 2009-2013, the telemetry data from Kootenay Lake receivers suggests 10 – 20% of them are using the lake.

  • We expect these steps, among others, will lead to the restoration of viable and naturally spawning burbot populations in and around Kootenay Lake, though not immediately.

  • And, Moyie Lake burbot were tested for IHN virus and are not infected.

 

 

 

 

Kokanee salmon  hit with virus

 

     Biologists will be keeping a close eye on kokanee as they return to the lake from their spawning grounds this spring. The salmon is infected with a virus that spreads fish to fish.

 

     A virus found in kokanee salmon on Kootenay Lake has biologists taking action to protect this “keystone species.”

The virus is called infectious hematopoietic necrosis or IHNV and was first discovered last fall during routine fish health testing at the Meadow Creek spawning channel. Further investigation found kokanee in Meadow Creek, Red fish and the Lardeau waterways had IHNV. It’s presumed those in the Kokanee spawning channel are infected as well.

“It seems to be throughout Kootenay Lake at present,” said senior fisheries biologist Jeff Burrows with the Ministry of Forest, Lands and Resource Operations. “We’re concerned because kokanee are not only a sport fish, they’re a keystone species in the whole Kootenay Lake food web. So many animals rely on kokanee — bears, osprey, even mallard ducks eat the eggs. They’re important.”

 

      He explained that Kokanee successfully spawned last fall and eggs were tested and found to be virus free. Transmission appears to be between adult fish rather than from fish to offspring.

“But the reason it’s of concern is that young fry are very susceptible and can die so when they hatch this spring in the spawning channel, they might catch it,” said Burrows.

     Upon learning of the virus’ presence, local spawning channels were flushed to “hopefully wash out the virus that might otherwise have lingered until now,” said Burrows.

     Fish carcasses, presumably virus laden, that died after spawning according to their natural life cycle were also removed.

“We’re hoping that will, at least if not prevent, mitigate the risk to fry,” he said.

     Burrows said this spring fish will be monitored and sampled for IHNV as they integrate into the main lake. This summer when regular maintenance to channels occurs, they will be completely shut off and dried out which will also kill the virus.

While the virus is commonly found in trout and salmon throughout Western North America, it hasn’t been found in the Kootenay throughout the past 20 years. It currently isn’t found in Arrow Lakes or the Upper Kootenay Lake.

     “We actually don’t know why IHN has turned up or where it came from in Kootenay Lake,” Burrows said.

There are two separate “stocks” of Kokanee with the population in the West Arm on the rise. However, 2013 numbers in the main lake, 200,000 spawners, are as low as they have been since records began in the mid-1960s.

     “It’s not unprecedented. It’s been this low before but it is as low as it has gotten in that time period,” said Burrows.

He explained factors other than the virus are at play, including high predator rates. Regardless, an illness in the lake isn’t “welcome.”

Other fish such as rainbow and bull trout along with white sturgeon can get the virus. Gerrard rainbow trout rely on Kokanee as their sole food source and that contact could mean they are susceptible, said Burrows.

This spring, the Ministry also plans to collect and test ovarian fluid from Gerrard as they return to the Lardeau channel to spawn.

 

There is no risk to humans or other animals from IHNV.

Mike Jeffery (chair) of Eastshore Freshwater Habitat Society accepting $1000.00 grant donation cheque from Karol Draper representing Nelson and District Credit Union Eastshore Branch. The Eastshore Freshwater Habitat Society would like to thank the Credit Union for locally supporting our fish habitat org.

This will help in purchasing electronic equipment to do fish and wildlife surveys and data in our local creeks and lakes to further our remediation of kokanee and other fish species. This is important to our local community awareness.