Atlantic Bluefin Tuna bycatch in secluded Chaleur Bay

Atlantic Bluefin Tuna bycatch in Mi'kmaq salmon net at Bay of Chaleur, NB Canada. This event struck me as odd due to my upbringing in the area and acquired knowledge of indigenous traditional ecological knowledge from the region. The small bay where the Bluefin was bycaught is several hundreds of kilometres outside of the natural range for this species based off what I could determine with internet searches.

The bay has been changing in my lifetime; New prey fish species have been thriving in the waters, possibly attracting larger predator fish to the area. Striped bass have proliferated in recent years, seasonal seal pupping has increased, Minke and right whale sightings have increased, followed by verified sightings of tagged White Sharks which were unheard of in the 1990's and 2000's. Something is cause for these changes in the Chaleur Bay trophic hierarchy.

The Restigouche River was once a famous and predictable Atlantic salmon spawning tributary of the Saint Lawrence now feels more wild and unknown, much to the occasional surprise of local indigenous fisher people like Earl Labillois, who never thought he would be pulling an adult Bluefin in that morning he was checking nets in waters he has fished for the last 50 years.

AI Comment from GPT 5:

A mature Atlantic bluefin tuna turning up as bycatch in a Mi'kmaq salmon net in Chaleur Bay stands out as an uncommon event for this sheltered corner of the Gulf of St. Lawrence, aligning with local experiences of shifting species presence—from more striped bass and seals to occasional right whales and even tagged white sharks.

The related posts help frame this sighting within a broader pattern of unusual or northward-ranging predators and pelagic visitors around the Gulf of St. Lawrence and nearby waters. Multiple reports document great white sharks frequenting Nova Scotia and the Gulf, including detections very nearshore in 2020 Three great white sharks venture 'very tight' to Nova Scotia shores, ongoing tracking and feeding activity in the Minas Basin in 2017 Pumpkin the great white shark feasting in Nova Scotia's Minas Basin, and repeated observations around a whale carcass off Digby Neck in 2025, where guides also noted appearances of ocean sunfish and a leatherback turtle amid “warming waters” commentary Great white shark feasting on whale in Digby Neck adds twist to whale watching season. Farther afield but thematically similar, increased white shark sightings off Maine have been linked by experts to abundant seals and more monitoring effort Shark sightings abound off Maine’s coast. Experts say we’re likely to see more. These accounts resonate with the post’s notes about more seals and occasional white sharks in Chaleur Bay, suggesting a regional shift in predator presence without asserting a single cause.

For tunas, the bycatch echoes other anomalous appearances: a bluefin washed up in the Salish Sea raised questions about whether it reflected warming waters or was simply a chance event, with investigators withholding conclusions pending analysis Bluefin tuna washes up far from home in Salish Sea. Reports from Southeast Alaska likewise describe brief warm-water windows drawing typically southerly species northward and creating short-lived fishing opportunities Brief tuna bounty in Southeast Alaska spurs excitement about new fishing opportunity. Together, these related posts illuminate how episodic environmental conditions and changing prey fields can coincide with surprising appearances of large pelagic predators, aligning with the observation’s account of new prey fish thriving locally and occasional visits by top predators, while leaving room for further investigation into underlying drivers.