Heat wave closes salmon pools on 2 New Brunswick. rivers

Gail Harding · CBC News · Posted: Jul 31, 2019 1:40 PM AT | Last Updated: July 31st

DFO says warm water temperature causes stress in Atlantic salmon

Salmon pools on two New Brunswick rivers have been closed because high water temperatures during the current heat wave are stressful to fish, Fisheries and Oceans Canada says.

A stretch of the Nepisiguit River from the dam at Grand Falls downstream to the mouth of the river is closed to angling except between 6 a.m. and 11 a.m.

On the Miramichi River, 27 salmon fishing pools have also been closed to angling, except between 6 a.m. to 11 a.m. The affected areas include:

Northwest Miramichi River upstream to its junction with the North and South branches, not including tributaries;

Little Southwest Miramichi River including the North Pole Stream and the Lower North Branch Little Southwest Miramichi River, not including tributaries;

Big Sevogle River including the North and South branches, not including tributaries;

Southwest Miramichi River including the North and South branches, not including tributaries;

Rocky Brook and Clearwater Brook, not including tributaries;

Renous River including the North and South branches, not including tributaries;

Dungarvon River, not including tributaries;

Bartholomew River, not including tributaries;

Cains River, not including tributaries.

The closures for angling are triggered when the water temperature reaches an established level.

The department said in a release that because Atlantic salmon is a cold water species, it can experience temperature-related stress or exhaustion when the minimum water temperature stays above 20 C, which can cause death.

"We are experiencing a period of warm temperatures in the air as you have seen but also in the water," said Frédéric Butruille, regional senior fisheries and aquaculture management officer.

"Angling can be detrimental to the survival of salmon when it is done in warm waters."

Butruille said the water temperature has to be above 20 Celsius for 48 hours before a closure is considered.

"How hot is it? We have seen two days in the Nepisiguit where the average temperature stayed above 20 degrees Celsius, so it was time to act."

But Butruille pointed out that during the hottest part to the day the river reached 28 C. 

With high temperatures, Atlantic salmon seek refuge in cooler parts of the river or brooks and sometimes bunch together. Butruille said some will still take a fly but if they are stressed and exhausted from the fight, they could die after being released.

While this is the first angling closure on the Nepisiguit River, Butruille said there has been previous closures on the Miramichi River where a water temperature protocol has been in place for seven years.

"The anglers are very sensible to everything that can harm salmon. They are very concerned of the state of salmon in general so we have a good collaboration and everybody I work with wants to protect salmon as much as possible and do the right thing."

Fisheries and Oceans will issue a notice when conditions have improved enough to reopen angling in the affected rivers.

Clarifications

An earlier version of this story incorrectly said a stretch of the Nepisiguit River was closed to angling all day. In fact, fishing is allowed between 6 a.m. and 11 a.m. Aug 01, 2019 3:02 PM AT