EXPLORE MIRISSA

Fin Whale

Complete Guide to Fin Whales in Mirissa, Sri Lanka

Fin whales are among the rarest yet most spectacular whales occasionally sighted off Mirissa, Sri Lanka. Known as the second-largest animal on Earth, fin whales (Balaenoptera physalus) are fast, powerful, and highly migratory baleen whales. While not as commonly seen as blue or Bryde’s whales, confirmed sightings in Mirissa highlight the extraordinary biodiversity of Sri Lanka’s southern waters.

Mirissa’s proximity to deep offshore waters and submarine canyons places it within the migratory corridor of fin whales moving through the northern Indian Ocean. When conditions align, Mirissa becomes one of the few places in South Asia where these giants may be observed from whale-watching vessels.

What Species of Fin Whale Is Seen in Mirissa?

The species recorded in Mirissa is the Fin Whale (Balaenoptera physalus), a globally distributed rorqual whale found in both temperate and tropical oceans.

Fin whales are recognised for their:

  • Immense size

  • Streamlined body

  • Exceptional swimming speed

Why Fin Whales Choose Mirissa:

Fin whales are drawn to waters off Mirissa due to:

  • Deep offshore feeding zones

  • Seasonal productivity driven by ocean currents

  • Krill and small schooling fish availability

  • Sri Lanka’s position along major whale migration routes

Although fin whales are not resident, Mirissa lies within an important transit and feeding zone during migration.

Size, Length & Weight of Fin Whales in Mirissa

Fin whales are the second-largest whales on Earth, surpassed only by blue whales.

Accurate Size Measurements:

  • Average length: 18–22 metres

  • Maximum length: Up to 24 metres

  • Average weight: 40–70 tonnes

  • Calves at birth: Around 6–6.5 metres

Fin whales sighted near Sri Lanka are typically fully grown adults, making encounters extremely impressive.

Why They Grow This Large:

Their massive size allows fin whales to:

  • Store energy for long migrations

  • Efficiently filter-feed large volumes of prey

  • Maintain speed and endurance in open ocean conditions

Their streamlined form earns them the nickname “the greyhound of the sea.”

Colour & Appearance of Fin Whales in Mirissa

Sperm whales have a rugged, battle-scarred appearance that reflects their life in deep, challenging ocean environments.

Colour & Patterns:

Fin whales display a striking, asymmetrical colour pattern:

  • Dark grey to brownish-grey upper body

  • Lighter underside

  • Right lower jaw is white, left side dark

This unique jaw colouring is a key identification feature.

Distinct Physical Features:

Notable characteristics include:

  • Long, slender body

  • Tall, sharply curved dorsal fin

  • Flat, V-shaped head

  • Smooth skin with minimal scarring

When surfacing in Mirissa’s clear waters, their elongated body often becomes visible just beneath the surface.

How to Identify a Fin Whale in the Mirissa Sea

Fin whales can be distinguished from other large whales by a combination of size, shape, and movement.

Main Identification Signs:

1. The Blow (Spout):

  • Tall, vertical blow

  • Can reach up to 6 metres high

  • Less bushy than a blue whale’s

The blow is often the first sign of a distant fin whale.

2. Head Shape:

  • Flat, pointed rostrum

  • Asymmetrical jaw colouring

  • Sleek, hydrodynamic profile

3. Dorsal Hump:

  • Prominent, falcate dorsal fin

  • Positioned far back on the body

  • Visible shortly after surfacing

4. Dive Sequence:

Fin whales:

  • Rarely raise their tail flukes

  • Perform smooth, shallow dives

  • Travel long distances at the surface

This fast, linear movement pattern is typical of fin whales.

Fin Whale Diet and Feeding Behaviour in Mirissa

Feeding Facts:

Fin whales are baleen feeders that consume:

  • Krill

  • Small schooling fish

  • Copepods

They can consume over one tonne of food per day during peak feeding.

Feeding Techniques in Mirissa Waters:

In Sri Lankan waters, fin whales use:

  • Lunge feeding

  • Side-rolling to exploit prey density

  • Fast acceleration through prey patches

Feeding usually occurs offshore, which explains their less frequent sightings compared to coastal-feeding species.

Fin Whale Season in Mirissa: Best Time for Sightings

⭐ Peak Season:

December to March

  • Calmer seas

  • Increased offshore productivity

This period aligns with major whale movements through the Indian Ocean.

Shoulder Months (Possible Sightings):

November and April

  • Sightings are rare but possible

  • Sea conditions may vary

Fin whale sightings in Mirissa are opportunistic rather than guaranteed, making each encounter especially significant.

Where Fin Whales Are Found in Mirissa

Why This Matters:

Understanding their location helps:

  • Set realistic expectations

  • Support ethical whale watching

  • Protect migratory routes

Typical Habitat Range:

  • Far offshore waters

  • Depths exceeding 1,000 metres

  • Along submarine canyon systems

Fin whales prefer open ocean environments, unlike Bryde’s whales that feed closer to shore.

Behaviour of Fin Whales in Mirissa

Social Behaviour

Fin whales are usually:

  • Solitary

  • Seen in pairs

  • Occasionally in small groups

They are less social than humpback whales and rarely interact with vessels.

Diving and Resting Behaviour:

  • Short, shallow dives

  • Long-distance surface travel

  • Brief surface intervals

Their speed and directionality make them challenging but thrilling to observe.

FAQ: Fin Whales in Mirissa, Sri Lanka

Are fin whales commonly seen in Mirissa?

No. Fin whales are rare visitors, but confirmed sightings do occur.

How are fin whales different from blue whales?

Fin whales are smaller, faster, and have a distinctive asymmetrical jaw colour.

Do fin whales migrate through Sri Lanka?

Yes. Sri Lanka lies within an important migratory corridor for fin whales.

Is it safe to watch fin whales from boats?

Yes, when vessels follow international whale-watching guidelines.