Impact of fish whirling disease remains unknown


Until Alberta Environment gets a better picture of how evolved the parasite that causes fish whirling disease is, recreational users of the Bow River are cautioned to exercise vigilance and ensure their vessels, fishing equipment and even the mud on their boots is not leaving one body of water and entering another.

That means draining all vessels and boating/watercraft/fishing equipment; allowing it to dry out for a 24 hour period before placing it in another body of water; never releasing live bait into a body of water; and possibly sanitizing equipment.

“Are we about to see it unfold or has it been around for 20 years already? ” asked Kevin Fitzsimmons, a senior biologist in Cochrane with the Alberta Conservation Association.

“I think it really depends on where we are in the evolution or progress of the parasite. ”

For Cochrane fish guru and director of Bow Valley Habitat Development, Guy Woods, he sees the disease as potentially a “major concern as a sport angler ” and as having an even bigger potential impact on the entirety of the ecological system- to be determined through further research to establish how long the parasite has been lurking in these waters.

The Canadian Food Inspection Agency (CFIA) said the disease infects juvenile fish and causes them to whirl around in circles. Whirling disease, which infected fish in the in Bow River in Banff National Park last August, has a mortality rate of up to 90 per cent.

Multiple locations along the Bow River through south Calgary have since been confirmed, both upstream and downstream of Cochrane – including at least one government-licensed commercial aquaculture facility.

The Eagle attempted to contact nearby fish farm, Allen’s Trout Farm. A voicemail recording stated it was “closed due to unforeseen circumstances until further notice ” and to contact Smoky Trout Farms as it is “the only (fish farm) currently open in Southern Alberta ”.

According to Max Menard of Smoky Trout Farms the facility tested negative last fall, but the entire aquaculture industry is “in limbo ” and he is uncertain how many other private facilities have faced temporary closures due to the disease.

He said the discovery last year was an “upheaval ” as fish whirling disease has been “off the radar ” for many years and was considered to only be a problem in the U.S, adding there is likely more testing, stringent regulations and mitigation measures on the horizon.

He said the discovery will likely result in a shortage of fish on the private sector side until next year.

Smaller, private facilities such as Smoky Trout Farms stock residential or small town-owned ponds, while government facilities stock lakes. Unlike other industries, such as cattle, Menard said the CFIA does not compensate for aquaculture losses – possibly because it’s deemed a high-risk industry.

According to Brett Wittmeier, spokesperson for Minister of the Environment Shannon Phillips, the ministry is “working the CFIA to quarantine fish farms and hatcheries to prevent the spread of whirling disease, which may affect the number of fish stocked for the 2017 fish season. ”

Mitford Pond has long been Cochrane’s favourite training grounds for young anglers, as children ages 12 and under are allowed to fish in the stocked pond that reaches a maximum depth of 15 feet. Children are allowed to keep one fish per day during the fishing season. The pond is catch and release for adults.

Gerry Murphy, parks and open spaces manager for the town, said it remains to be seen what the impact will be on the availability of fish stock.

“We are hopeful we can find a supplier with a clean bill of health, ” said Murphy, adding that they usually stock the pond with rainbow trout in the beginning of the season (April), again around a week before the annual Kids Can Catch event (June) and sometimes in the early fall.

Last year, brown trout were successfully added for a total stock of around 1,200 fish throughout the season.

“At this point we don’t know when and if we’re going to stock, ” he said, adding that he is awaiting further direction from the province.

The parasite, Myxobolus cerebralis, primarily affects most species of trout, most notably rainbow trout, and whitefish (all species found in the Bow River), according to the CFIA.

The disease cannot be transmitted to humans and poses no danger to human health if a diseased fish is accidentally consumed; it has no ill effect on drinking water either.

The main concern is how this disease may impact local fish populations and the ecosystem as a whole.

“It’s not known yet what effects whirling disease will have on our fish populations, but there are no plans for closures at this point, ” said Wittmeier.

“Alberta Environment and Parks is working with Parks Canada and the CFIA to determine the full extent of fish whirling disease, including testing the Bow River and tributaries, as well as the Oldman River and upper Red Deer River watersheds, ” said Wittmeier.

He added, “Given the life cycle of whirling disease and time required to observe infected fish, it is likely that it was present prior to 2016. ”

The parasite may cause skeletal deformities on the skull or head and the tail of the fish may appear dark or black; it cannot be transmitted between fish, rather through a freshwater worm carrying the parasite. Not all infected fish show physical symptoms.

While humans are generally regarded as the culprits of contamination, any fish-preying species (typically birds) that potentially travel between water bodies have the ability to worsen the problem.

“That’s the alarming thing about it – it’s good to have anglers take precautions, but they are not the only cross-contaminators, ” said Woods, who is hopeful that if the problem persists, Alberta Fish and Wildlife will make exceptions in catch and release areas so that anglers can turn in suspect fish that physically appear to be carrying the disease.

According to Alberta Environment and Parks, if a fish is caught and is suspected of carrying fish whirling disease it can be placed in a sealable container or bag and an Alberta Fish and Wildlife officer should be contacted; if the fish is under regulation to be released, however, anglers cannot keep a suspect fish for further testing by an officer.

Fishing season for Cochrane anglers:

Ghost Reservoir is open all year (Trout limit 5; Mountain Whitefish limit 5 over 30 cm; Bait allowed.

Ghost River Wilderness Area (All waters) is closed all year

Ghost River (downstream of Ghost River Wilderness Area) and tributaries except Waiparous Creek:

From June 16 to Aug. 31 – Trout limit 0; Mountain Whitefish limit 5 over 30 cm; Bait Ban.

From Sept. 1 to Oct. 31 – Trout and Mountain Whitefish limit 0; Bait Ban.

From Nov. 1 to June 15 – Closed

*Note: A correction to wording was made in this story. the original article phrasing made it sound as though 90 per cent of fish in the Bow River around Banff had died to whirling disease. The statement should have reflected that up to 90 per cent of fish infected with the disease die.


About Author

Lindsay Seewalt

Lindsay is a senior Eagle reporter who has transformed her penchant for storytelling into the craft of writing. She has a knack for getting the scoop on stories and is a strong interviewer. The U of C and MRU English/Journalism graduate is committed to telling every story through a new lens, from a fresh perspective. Currently, her focus is on news and politics reporting, including town hall. She has a passion for providing a platform for underdogs, grassroots movements and those who have the courage to put themselves out there. She bases the strength of her stories on the depth of her connection with her interviewee, which is best done over too much coffee.