Exploits’ abnormally high water temperatures concern conservationists
© Andrea Gunn photo
Vast and beautiful, the Exploits River has been a popular location for salmon anglers for decades. But this year’s abnormally high temperatures have been causing problems for the cold-water Atlantic salmon that inhabit it’s waters.
The great Exploits River has been regarded by fishing enthusiasts as a world-class location for salmon angling for the better part of thirty years.
Known as a stocked river, meaning the population of Atlantic salmon was increased through human means, Fred Parsons of the local Environmental Resources Management Association (ERMA) called it the second largest producing river of Atlantic salmon in North America.
ERMA runs the Salmonid Interpretation Centre on the Exploits in Grand Falls-Windsor; the centre is responsible for gathering and interpreting data on the yearly salmon run for conservation purposes, and is also a popular tourist spot. While not a biologist, as the General Manager of ERMA, Parsons knows his fish.
And he knew pretty early this summer something strange was going on.
“This has been an oddball year right from the start,” he said “We have a lot of data on the Exploits River. We know when the fish should be moving, when the run should peak…but if (we’re correct) 19 times out of 20, well, this is the 20th time.”
The first warning sign this summer would not be like any he’d seen before, he said, showed up in June.
“Not only on the Exploits, but on a lot of the other rivers, everyone kept saying ‘this is going to be such a marvelous year,’” said Parsons, adding that fishermen familiar with the river know that the annual run of salmon peaks around July 14.
“If you talk to any anglers across the island they’ll say ‘no, no, you don’t fish the Exploits until at least the first week in July,’” he said. “The Exploits just isn’t an early river.”
But this year it was – according to Parsons, the run peaked on June 28, weeks earlier than the normal time frame.
In hot water
While the early run was an extremely rare occurrence, Parsons said, it’s not necessarily a sign of something bad. But there is something else that has conservationists very concerned.
“The thing that will be talked about for years is that we’ve been in summer since early June, which has driven the water temperatures pretty crazy,” he said.
Though the hot, sunny weather that has been upon the region since late May is a fisherman’s dream, Parsons said it’s not so great for the fish.
“I’ve been around a long time, and I don’t know if I’ve ever seen temperatures so high.” –Fred Parsons, ERMA
According to Parsons, when water temperatures rise, dissolved oxygen content actually decreases.
“It’s the equivalent of humans being in a smog city.”
Parsons said the ideal water temperatures for Atlantic salmon, a cold-water species of fish, is around 15 degrees Celsius, and after 18 degrees, they go into survival mode.
This year? The temperatures have been closer to 21 and 22 degrees in the main stem of the Exploits, and with low water levels, as high as 27 in tributaries.
“Anything above 22 or 23 could be dangerous to fish,” he said. “I’ve been around a long time, and I don’t know if I’ve ever seen temperatures so high.”
He said fish in water this warm become sluggish, and sometimes stop eating.
It also means salmon anglers won’t be getting many bites.
“The fish know they only have so much energy, they’re really in survival mode so they aren’t wasting time playing with fishing flies.”
What’s even more concerning for Parsons, is that earlier this summer, the salmon population was at least getting reprise from the heat at night – that isn’t the case anymore.
“In the last number of days it’s just not cooling down,” he told the Advertiser on Friday.
According to Parsons, the Exploits River, which has seen yearly counts as high as 50,000 has had only 29,000 fish go through this year, and said he only expects a couple of thousand more.
“The numbers for the season are down, we’re running about 8,000 behind last year,” he said.
Parsons added that the environmental conditions aren’t to blame completely for the low numbers, he said salmon have a five-year span, and around five years ago the numbers were a little low.
While the prime fishing season coming to an end soon, Parsons said there’s a slight chance things could pick up for anglers when the fall season rolls around, but it’s unlikely.
“Things would have to change a lot in the next three to four weeks.”