Kananaskis logging threatens at-risk trout: Study

A planned logging operation in the upper Highwood River watershed threatens critical habitat for at-risk trout species, raising concerns over increased erosion, sedimentation and altered stream flows that could harm sensitive fish populations.

A new report from the Canadian Parks and Wilderness Society (CPAWS) and Freshwater Research Ltd. found lumber company West Fraser’s 1,100-hectare logging plan poses a high risk of significant changes to watercourses, riparian zones, and hillslopes in the Loomis Creek watershed – a tributary of the Highwood River – due to increased peak flows and surface erosion.

“We looked at how logging was affected by the requirements under the Species at Risk Act, and not surprisingly found that, effectively, the main conclusion there is that there’s no way that they can do this logging without impacting critical habitat and residences – which are actually the egg nests of the redds, and also the fish themselves,” said Dave Mayhood, president and principal consultant of Freshwater Research Ltd.

“All of those factors are not allowed very clearly under the Species at Risk Act.”

Redd refers to the spawning bed of trout in a watercourse. They are formed by trout beating the rocks with their tail-fin and can be identified by a bowl-shaped indentation of clean bright rocks. Trout do this to remove moss, dirt, bigger rocks, and debris.

Bull and westslope cutthroat trout are listed as threatened in the federal Species at Risk Act and the Highwood River is identified as a high value watershed with important aquatic habitat for both species. However, sediment delivery due to logging road erosion and expected increases in peak flows from removing forest from parts of sub-watersheds threatens to smother species recovery.

Mayhood, an independent aquatic ecologist who holds degrees in zoology and the ecology of inland waters, has more than 50 years experience in the field and has conducted more than 130 assessments of small watersheds on southern Alberta’s Rocky Mountain eastern slopes.

He warns that logging roads, water crossings and inadequate tree cover as a result of clearcutting next to streams and higher peak flows will add sediment to the many small tributaries in the area that feed into the Highwood River.

“Sediment increases tend to be chronic once something like a logging road system is developed into an area,” said Mayhood.

Less tree coverage also increases the likelihood of increasing stream temperatures. Loomis Creek waters measure around 13 Celcius in the summertime and bull trout need clean, cold water to survive and compete with other fish species.

“Just a change of one degree in maximum temperature in that creek would have the effect of weakening the ability of these trout to resist invasion of populous rainbow-cutthroat hybrid trout in the main stem of the Highwood River,” said Mayhood.

Particularly concerning is the plan to log a significant portion of watercourse lengths without any riparian buffers. According to West Fraser’s current plan, 22 of the 36 area sub-watersheds will have over 25 percent of their watercourse lengths left unprotected.

“It seems like a very small thing, but logging can increase temperatures in streams even when they’re buffered with a buffer strip that is left alone and not logged at all. You can get increases of up to five Celcius in the water temperature, and that only has to happen in one season and these fish have lost ground to their competitors,” said Mayhood.

“In the end, we end up with damaged or destroyed fish populations that are supposedly fully protected under the Species at Risk Act.”

The study also looked at the risk of flooding during peak flows and summer low flows, which are associated with drought.

“Removing effective forest cover in this area is likely to increase flood risk by increasing the frequency and magnitude of peak flows,” it stated. “It may also reduce late-season water availability by advancing the onset of low flows to earlier in the season.”

Josh Killeen, conservation science and programs manager for CPAWS Southern Alberta, said it’s expected that climate change will exacerbate hydrological changes.

While Killeen and Mayhood were conducting watershed assessments for the area, another report was commissioned by Alberta Forestry and Parks to assess potential for hydrological alteration and risk associated with logging.

Mayhood obtained that report through a Freedom of Information and Privacy request and shared it with the Outlook.

To Killeen’s point, it noted that changes in climate are likely to compound some hydrologic effects of forest disturbance, including increases in peak flows and earlier peak flow timing.

“The hydrological model projects a higher and more volatile extreme peak flow regime under the climate change scenario; this increased variability suggests hydrologic alteration could be considerably higher than projected under historical conditions,” states the report, completed by MacHydro.

While no fieldwork was undertaken for the study, it recommended future assessments look at what degree of hydrologic alteration is unacceptable, as well as periodic evaluation of the change in hydrologic indicators on an ongoing basis.

The report further acknowledged the Highwood River is a high value watershed for its aquatic habitat for westslope cutthroat and bull trout, as well as an important source of water for irrigation and communities in southern Alberta.

Killeen and Mayhood’s report, which did not take the MacHydro report into consideration, unbeknownst of its existence at the time, also calls for further on-the-ground analysis, specifically from a hydrologist and a fish biologist team.

“We’ve recommended that both to West Fraser and to the forestry and parks government regulator,” said Killeen. “We see it as being a really important part of actually understanding the distribution and the populations status of bull trout and westslope cutthroat trout, as well.”

Little is known about the status of the two species populations in the Highwood River and Loomis Creek, however, CPAWS commissioned a study that was completed in winter 2023-24 and funded by the Bow River Trout Foundation, which proved – using environmental DNA (eDNA) sample collection – that bull trout are present and spawning in a much larger area than previously known.

Over the study period, bull trout eDNA was strongly detected in all three sample sites in Loomis Creek near Bishop Creek in late November, when much of the creek was covered in ice.

The site furthest upstream on Loomis Creek was approximately 3.2 kilometres upstream from the Highwood River and 520 metres downstream from the confluence of Bishop Creek.

The study further noted the Fisheries and Wildlife Management Information System shows two electrofishing records of bull trout captured in Loomis Creek. One record from 1989 was upstream of Bishop Creek, where three fish were captured, and another record from 2008, further downstream, recorded two fish captured.

“Considering two previous electrofishing captures, as well as records of spawning activity, Loomis Creek is likely used by bull trout throughout the year, supporting all life stages of the species,” the study, titled Winter Environmental DNA Survey for Bull Trout in Loomis Creek, noted.

Shortly after that study was released, and after Spray Lake Sawmills was bought out by B.C. lumber giant West Fraser, the company announced it was pausing its logging plan in the Upper Highwood in February 2024 to further consult interested parties. It was initially set to begin harvest operations in winter 2023-24.

“We are now in the process of meeting with local groups that are interested in sharing information regarding forestry operations in the region,” the company stated at the time. “We will work to incorporate actionable information that we garner through these conversations into our future harvest plans for the Highwood.”

The announcement also came after the Department of Fisheries and Oceans launched an investigation into the lumber company prematurely building a bridge over the Highwood River to access logging operations. When activities and infrastructure building are planned that could damage critical habitat for a threatened species – federally listed and subject to protections and recovery strategies under the Species at Risk Act – a company must apply to the federal fisheries agency for a permit.

Based on what was presented at West Fraser’s annual open house earlier this month, no changes have been made to the logging plan. 

Joyce Wagenaar, director of communications for West Fraser, said the plan is still paused as the company continues to seek out actionable feedback.

“No revisions to the plan have been made at this point as we are still collecting and assessing information. Once that is completed, we will provide an updated plan,” she said in a statement.

“The timing for proceeding will not be determined until the feedback has been incorporated into the plan and the necessary government authorizations are obtained. We are currently in discussions and working with the Department of Fisheries and Oceans on a solution. As this work progresses and we finalize the decision, we will have more to share.”

Killeen said this much was unclear based on what was recently presented to the public. 

“From what I saw at the open house, the plans appear to be essentially the same as they were prior to West Fraser announcing the pause, and they also listed in the general development plan that was posted on their website along with it that the Highwood was scheduled for harvest this winter, so 2024-25,” said Killeen.

“I don’t know if there was some confusion there or what was going on, but we were surprised to see it in the plan like that with no mention of the pause or ongoing consultation. We’ve still been meeting with the company with the impression that they are consulting, but at the same time they are presenting the plan as going ahead at the open house.”

Killeen and Mayhood still see regulation under the Species at Risk Act and the 2020 Recovery Strategy for bull trout as the firmest grounds to stand on in defence of the Upper Highwood watershed. The recovery strategy calls for riparian setbacks of at least 30 metres to protect critical bull trout habitat.

“This 30m riparian area is necessary to protect key stream attributes such as clean and cold water with low sediment and silt, maintain channel configuration and habitat structure, and provide terrestrial food inputs and woody debris into the aquatic environment,” the recovery strategy states.

For westslope cutthroat trout, the Department of Fisheries and Oceans initially proposed a 100m riparian buffer in the draft federal recovery plan, but Alberta government officials challenged this, resulting in a 30m buffer being adopted.

“But that still doesn’t line up with how West Fraser operates under provincial regulations,” said Killeen. “For these smaller watercourses, the provincial regulations give only very small buffers or none at all, while the Species at Risk Act and associated recovery strategies are calling for these larger 30m buffers.

“When we look at the plans, there’s no sign of those larger buffers on those smaller watercourses like Loomis Creek. There’s a mismatch there between what’s in the provincial regulations and what’s in the recovery strategies that define critical habitat.”

Killeen said provincial and federal regulations need to align and be enforced as a first step.

Step two would be having a more fulsome assessment requirement for Alberta native trout in the forest management planning process.

 “At the moment, we see that there’s a lot of damage done to critical habitat on quite a regular basis, and of course that makes it really challenging for these species to survive and recover.”

The Local Journalism Initiative is funded by the Government of Canada. The position covers Îyârhe (Stoney) Nakoda First Nation and Kananaskis Country.