- Created: Thursday, 14 December 2017 15:30
Studying Sedimentation to Protect Native Trout
By Ann Sullivan
Conservation biologists tend to be a grumpy bunch, according to Dave Mayhood. But with help from stewardship organizations like the Elbow River Watershed Partnership, maybe Mayhood and his colleagues will start feeling positive about changes in Alberta’s water bodies and riparian zones.
Mayhood, an aquatic ecologist and president of FWR Freshwater Research Limited, has been working to bring attention to the state of Alberta’s native Westslope Cutthroat Trout as their population declines and sedimentation of their habitat increases. He is currently researching sediment loading to several streams in the McLean Creek Public Land Use Zone (PLUZ), one of the few remaining areas with genetically pure stocks of Westslope Cutthroat Trout.
One hundred years ago, Westslope Cutthroat Trout were an abundant species in the Upper Bow and Oldman River systems and mostly likely the Milk River too. These days there’s almost nothing left of those pure stocks. It’s a classical conservation issue, says Mayhood: a very small population in a fragmented and highly unproductive habitat. Some of the creeks in which cutthroat are still found are tiny—just several kilometres long and narrow enough to easily jump across. Others, like Silvester Creek in the Elbow River watershed, are loaded with sediment from off-highway vehicle (OHV) traffic, pipeline rights of way and trail and road surface erosion.
Native cutthroat stocks started declining decades ago, through a combination of overfishing and hybridization with introduced trout species. About five year ago, the federal government listed the Westslope Cutthroat Trout as “threatened” under the Species at Risk Act (SARA). Mayhood would argue that the species is endangered, not just threatened, and notes that the government has created a recovery strategy for the species but still needs an action plan to save it.