Endangered Spotlight: Fin Whale (Balaenoptera physalus)

Fin Whale blow hole. Photo: S. Lyday

By Nina Bubert

Commercial hunting of fin whales was banned by the International Whaling Commission (IWC) in 1976.  This, unfortunately, does not guarantee them protection from humans.  Recently, a large container ship struck and killed a 47-foot fin whale as it made its way to the Port of Long Beach.  Crew members, including the Captain, were not aware the strike occurred until they pulled into the harbor. 

This tragic and unnerving incident was the first known whale strike this year.  Last year saw at least three and as many as five blue whales die at the mercy of these giant cargo ships.

In response to the blue whale deaths, a 10 knot speed was advised for ships entering Long Beach and Los Angeles ports, while a voluntary 12 knot speed limit was set for environmental reasons. Whale strikes by ships are inevitable if officials don’t set mandatory speed limits in these busy ports.

Fin Whales are among the largest animals on our planet, second only to the Blue Whale.  Still these majestic and endangered whales don’t have a fighting chance against a massive ship weighing over 1000 tons and as long a three football fields. A reduced speed would prevent strikes or reduce the impacts on the whale if a strike did occur.

Physical Description

Fin whales are found in all oceans of the world and can be found feeding off the continental shelf in Sanctuary waters.  They are long, slender, and streamlined making them the “greyhounds of the sea” able to reach speeds up to 23 mph. 

The fin whale is also referred to as the finback or razor back whale with a slightly curved fin located far down its back. Like most cetaceans, fin whales have counter shading, where their underside is white and their dorsal side is a grey to brownish black. 

The most unique, identifiable characteristic of the fin whale is the asymmetric coloring of the jaw.  The lower left jaw is black and the right side is a white creamy color.  The pattern even extends to the baleen but the tongue has the reversed pattern. 

Like the blue whale, fin whales feed on krill, but they also feed on schooling fish.  The fin whale is a type of baleen whale called a rorqual.  This means they have a series of 50-100 pleats lengthwise from the jaw to the navel.  These expand to allow large amounts of water into the mouth which can then be pushed out through the baleen trapping krill. 

Endangered Status

The global population of the fin whale has declined 70% over the last eighty years.  The North Pacific population has not had a comprehensive assessment since the 1970s.  Back then the subpopulation was estimated at 17,000, but the trend is unknown. 

The fin whale that was struck off Southern California waters was estimated to be a 1- 3 year old female. Females are important for population recovery because they represent potential additions to the population.  It is extremely important to reduce the impact humans have on fin whales in order for the extraordinary creatures to survive.