Salmon smolt falling prey to bass as they leave Miramichi River

The report,published this week in the Canadian Journal of Fisheries and Aquatic Sciences,estimates striped bass are eating twoto 18 per cent of salmon smolts. Smolts are young salmon that are ready to go to sea.

"I would say it's quite significant," said Jason Daniels, a biologist with the Atlantic Salmon Federationwho co-authored the study.

The estimated consumption rate comes as the population of striped bass in the Gulf of St. Lawrence explodes.Anglers reported seeing them from Cape Breton to Labrador, according to the federation.

Smolt survival down twofold since 2000s

In 2016 there were an estimated 318,000 striped bass in the Gulf,up from 5,000 in the mid-1990s.

"There's 300,000-plus fish moving intoone 10-kilometre section of river; that's a lot of fish to pack in there," said Daniels.

The report says salmon smolt survival in the Miramichiestuary is estimated to have fallentwofold since the mid-2000s.

Daniels saidit's the first study to quantify the degree of predation of smolts in the Miramichi by striped bass.

Between 2013 and 2016, the Atlantic Salmon Federation inserted miniature acoustic transmitters into 514 Atlantic salmon smolts in the Miramichi River.Dozens of receivers were placed in the river and estuary.

At the same time, stafffrom the Department of Fisheries and Oceans and the province of Quebec tagged 110 striped bass.

Transmitters differentiate between species

Receivers confirmed both species were in the same place at the same time,with unfortunate results for the salmon smolts.

"The more time they are hanging out together,the more likely predation is to occur," said Daniels.

Most importantly, the transmitters were specially coded to differentiate each species, allowing scientists to understand how each moved in the water.

The study indicates large numbers of smolts are being taken by stripers, but notes there are other threats in the Miramichi estuary, including the physiological stress associated with migration,and human causes like pollution.

The impact on adult salmon who eventually return to the Miramichi is not directly correlated.Daniels saidthe bass could be killing theweak who were doomed to die anyway.

"That said, 20 per cent of a population is certainly not helping anything."