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Fin Whale (Balaenoptera physalus)

Fin Whale is the second largest whale on Earth and a frequent visitor of Saint Lawrence River during summer. It is a fast swimmer and it likes to gather in groups for feeding.

At a Glance – Fin Whale

When is the best time to see Fin Whales in Québec?

The most consistent period is July to September, when Fin Whales use productive feeding zones in the St. Lawrence system.

• Peak season: Mid-summer through early autumn.
• Regional focus: Saguenay-St. Lawrence Marine Park and adjacent feeding corridors.
• Field pattern: Encounters are often brief because whales keep moving while foraging.

How can I tell a Fin Whale from other whales in the area?

Look for a very long streamlined body, a small dorsal fin set far back, and the usual absence of a raised fluke during dives.

• Compared with Blue Whale: Fin Whale is generally less bulky in profile.
• Compared with Minke Whale: Fin Whale is much larger and has a different surfacing scale.
• Compared with Humpback Whale: Fin Whale less often shows flukes and has a more elongated silhouette.

For practical local comparison, see Identifying Whales in Saguenay St. Lawrence Marine Park.

What does the Fin Whale eat in the St. Lawrence region?

Fin Whale is a baleen filter-feeder that targets dense prey patches.

• Core diet: Krill and other zooplankton.
• Also consumed: Small schooling fish such as herring, capelin, and sand lance.
• Seasonal dynamic: Feeding intensity rises in summer when prey is concentrated.

Identification and Similar Species

Fin Whale is identified by its very long, streamlined body, a small dorsal fin set far back, and a low, fast surfacing profile. It usually shows little to no fluke when diving, unlike species that regularly lift the tail.

In good light, look for the species’ classic asymmetry: the right lower jaw is paler than the left side.

For side-by-side field comparison in this region, see Identifying Whales in Saguenay St. Lawrence Marine Park.

Similar species

• Blue Whale (Balaenoptera musculus) - Larger and bulkier, with a broader blow and less prominent dorsal profile.
• Northern Minke Whale (Balaenoptera acutorostrata) - Much smaller, with quicker, lower-profile surfacing and a distinctly different scale in the field.
• Humpback Whale (Megaptera novaeangliae) - More likely to show flukes and has a very different body and dorsal-fin shape.

For practical field separation of these whales in the same region, see Identifying Whales in Saguenay St. Lawrence Marine Park.

Observed Behaviour - Québec (Field Recordings)

• 

  A Fin Whale surfaces smoothly in calm St. Lawrence water, showing its long back and low dorsal profile before slipping forward out of view.

Best Locations and Seasons for Sightings

In Québec, Fin Whale is a regular warm-season visitor of the Saguenay-St. Lawrence Marine Park and adjacent St. Lawrence feeding areas.

The most consistent period is July to September, when prey concentrations in the St. Lawrence system support repeated feeding activity.

Sightings are usually brief as whales transit and forage through open-water corridors rather than staying near one fixed shoreline point.

Ecology and Behaviour

Distribution

Fin Whale has a broad oceanic distribution across the North Atlantic and other major ocean basins, with seasonal use of temperate and higher-latitude feeding grounds (Wikipedia; EOL).

In eastern Canada, it is regularly recorded in the Gulf and Estuary of the St. Lawrence, including Québec waters, where summer feeding conditions are favourable.

The species is globally listed as Vulnerable, with current pressures including ship strikes, fishing-gear entanglement, and chronic underwater noise (Wikipedia).

Diet

Fin Whale is a filter-feeding baleen predator that takes dense prey patches through lunge feeding.

• Main prey: Krill and other zooplankton.
• Also taken regionally: Small schooling fish such as herring, capelin, and sand lance.
• Seasonal pattern: Feeding intensity increases in productive summer areas such as the St. Lawrence system.

References – Fin Whale

Most content on this page is based on my direct field observations. General species background (taxonomy, range, and broader ecology) is informed by the sources listed below.

• Identifying Whales in Saguenay St. Lawrence Marine Park - Local field comparison guide
• EOL - Taxonomy and species profile
• Wikipedia - Broad species overview and background
• DOI: 10.1111/eva.13091 - Evidence of hybridization between fin and blue whales

All content on this page — including photos, videos, and field audio recordings — was created by Karl-Heinz Müller, a Montréal-based wildlife filmmaker, sound recordist, and photographer. Founder of MUUUH and Québec Sauvage, he has spent over a decade documenting Canada’s natural habitats through immersive soundscapes and wildlife films. Learn more about Karl-Heinz

Last updated: 2026-05-27