Fin Whale Facts | Anatomy, Diet, Migration and Reproduction

The fin whale is a large baleen whale that belongs to the cetacean species, which is composed of all species of whaledolphin and porpoise.

Measuring in at up to 90 feet long they are considered the second biggest whale in existence in terms of length right after the blue whale.

These whales can be found traveling throughout the worlds major oceans, and only avoid a few areas such as the highest and lowest polar climates where large packs of ice may form.

Fin whales are solitary mammals that prefer traveling alone or in small pods rather than building long-lasting family bonds and relationships with large groups.

Physical Appearance and Anatomical Characteristics

In terms of appearance the fin whale is a brownish gray color with a paler whitish underside.

As stated earlier these whales can grow to be nearly 90 feet long (60 – 80 on average) and weigh as much as 130 tons.

Despite its large size this whale is relatively slender and streamlined allowing it to reach speeds of over 25 miles per hour for short periods of time.

The head appears almost v shaped and is flat on top and the dorsal fin is curved shaped resting near the back-end of the whale.

Its flippers are small in size and tapered when compared to other whales.

On average female fin whales will typically measure 5% – 10% larger than their male counterparts.

Diet and Hunting Methods

The diet of fin whales consists largely of crustaceans, krill, squid and fish.

In most cases these whales will travel in pods of up to 8 but may on occasion reach over 100 pod members during periods of feeding.

Fin whales are filter feeders and hunt their prey by swimming towards it with their mouth open consuming large amounts of food and water.

They then expel the water from their mouth while trapping their prey inside their baleen bristles.

The bristles act like a filter by allowing water to seep through the baleen bristles while preventing their food from escaping.

In some cases these whales have been observed working together by swimming in circles around their prey frightening them into a small ball.

The whales then swim towards their prey engulfing large amounts of food one at a time.

During deep dives these marine mammals have been observed holding their breath for over 15 minutes, however most dives are typically much shorter in length.

Habitat and Migration

As stated earlier the fin whale can be found traveling throughout the worlds major oceans with the exception of the coldest regions where large ice caps prevent travel or surfacing.

Although not much is known about their migration patterns it is believed that fin whales migrate to warmer tropical climates during mating season and to give birth, and migrate towards cooler waters during feeding season.

Social Structure and Communication

Fin whales are often found swimming alone or in small pods of up to 8, although they may be found swimming with larger groups of whales during feeding periods.

Like other species of baleen whales fin whales aren’t known for building long-term bonds and/or deep relationships with other whales.

When it comes to communication these whales communicate using loud low pitched sounds.

While the purpose of these sounds is unknown they may play a role in helping whales locate one another or attract a mating partner.

Mating, Reproduction and Lifespan

The average gestation period for the fin whale is about 12 months.

After birth the newborn baby whale may feed on its mother’s milk for a period of about 6 – 12 months.

When it comes to sexual maturity and reproduction male fin whales typically reach sexual maturity between the ages of 6 – 10 (not to be confused with physical maturity), while females tend to mature a little later between 7 – 12 years.

Fin whales can take up to 30 years to reach full physical maturity (maximum size) and may live for 90 years or longer.

Note: In rare occurrences there have been observations of an unamed fin whale/blue whale hybrid.

Threats and Predators

The only known natural threats to the fin whale is a pack of hungry killer whales.

Several observations of killer whales attacking fin whales have been observed.

In these cases the killer whales will chase and wear out the fin whale and then attack it by biting it and ramming it until the whale is unable to escape or run.

Killer whales may also flank the fin whale to block its escape while another killer whale sneaks up from behind or below the whale to attack and injure it.

When it comes to unnatural or man-made threats fin whales may face threats from collisions with ships, water pollution, global warming and over-fishing among other threats.

One of the most common causes of death among fin whales is due to these marine mammals being hit by large passing ships.

These collisions may either cause instant death or severely injure the whale causing it to either die from blunt trauma or end up beaching itself from confusion or as the tide washes its carcass ashore.

Over fishing may also causes issues among existing fin whale populations as these marine mammals struggle to maintain their food supply due to fisheries performing extensive fishing hunts on fish and other prey that fin whales consume.

Aside from declining food resources the fin whale may end up caught in fishing nets that were intended to capture fish causing them to drown because they are unable to return to the surface for oxygen.

In areas that contain water drills or in heavily commercialized areas noise and chemical pollution may threaten the existence of local fin whale populations.

Despite the end of the commercial whaling industry and bans put on hunting marine mammals some countries and/or companies still participate in hunting fin whales as a source of food.

10 Fin Whale Facts you may Find Interesting

  1. The fin whale considered a marine mammal, which means they are warm-blooded, breathe air, give birth and produce milk to feed their children.
  2. The fin whale is one of the largest animals in the world; second only to the blue whale.
  3. The scientific name for the fin whale is, “Balaenoptera physalus”.
  4. Due to the shape of their back and small pointed dorsal fin these marine mammals are also sometimes referred to as razorbacks.
  5. It is estimated that a healthy adult fin whale can live for up to 100 years.
  6. Due to extensive hunting during the whaling era these marine mammals are currently listed a protected species by the IWC.
  7. The only known natural predator to the fin whale is a pack of hungry killer whales.
  8. Fin whales can hold their breath for over 15 minutes when searching for food, however most dives are significantly shorter.
  9. During certain situation the fin whale has been known to travel at speeds in excess of 25 mph for extended periods of time.
  10. A single large adult fin whale (at 75 tons) can weigh as much as 10 large elephants (at 15,000 lbs. each)