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With a Vancouver-based greedy otter making the headlines in the provincial newspapers while she feasting on expensive fish and avoiding capture, Vanderhoof has her own otter problems.
The white sturgeon Nechako, a species listed under the federal Species at Risk Act (SARA), is preyed upon by an otter in the Nechako River watershed.
According to Wayne Salewski, Chair of the Nechako White Sturgeon Recovery Initiative Community Working Group, unlike Vancouver, where the SARA sturgeon faces a number of predators.
"I think we have otter families who, like all good guys, love fish."
The sturgeon travels the Nechako watershed up and down, swimming as far north as Lake Takla and up west Stuart Lake, but still returning to a stretch of water from downtown Vanderhoof to spawn.
The Nechako White Sturgeon Recovery Initiative in the Town operates a hatchery, captures female and male sturgeon, strips the eggs gently, returns adult fish to the river and then fertilizes them by hand to raise juvenile sturgeons . The young sturgeon are then released into the river on nine different sites, some with radio transmitters, to allow the initiative to track the fish and their survival rate.
Salewski says he has discovered in recent years that otters feed on juveniles in the river system.
"Over the years, we began to recognize that fish with radio transmitters seemed to fall prey to many otters. We would discover it by finding the radio transmitter on the coast, "says Salewski.
"More interestingly, we find many of these transmitters in the latrines otters. Otters are very social animals, very clean and like the same bathroom sites.
Salewski says the otter does not ingest emitters, but eats around them and spits them out. Nechako White Sturgeon Recovery Initiative volunteers can use their radios to find discarded transmitters, which are reusable, says Salewski. "It's a good thing about the whole situation."
The group has now begun to set up a program to discover the impact of otters on the overall survival and recovery of white sturgeon at risk.
Salewski says that this has been a learning curve from the beginning.
"With every year of experience, we must change our practices to increase the survival rate. In the early years, we put a fish in the water of a length of two to three inches. … We could quickly see things like seagulls invading our release sites and having a good age. That led us to say, "Well, we're going to raise them bigger and that should fix that problem."
But the bigger fish, from 12 to 14 inches, was an excellent forage for osprey and eagles, says Salewski.
"No self-respecting eagle would catch a two-inch fish, but it could easily catch a 12- to 14-inch fish."
Now the hatchery volunteers have decided to release the fish after two years.
"That's our reaction. … If otters are pursuing these [12-inch fish]perhaps if they were bigger and faster, perhaps an otter would not dispute the idea of taking them. This is where we are: superimposing our fish and see if it gives us a better survival rate. "
Salewski says the current low water levels do not help because visibility is good for predators.
"It's the circle of life. We are not naive, but many questions are left behind. Are we improving the health of otters because they now have a constant supply of food? And will the healthy mom produce more healthy babies and will our problem worsen because there are more? These are obvious questions and questions to answer, "says Salewski.
To learn more about the Nechako White Sturgeon Recovery Initiative, click here.
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