The Finback Whale - Balaenoptera physalus
One of the largest baleen whales is the finback whale, which is commonly sighted in the waters of the Gulf of Maine, from spring to fall. A member of the rorqual family, it has a pronounced dorsal fin and a series of throat grooves that expand when the animal is feeding. Other rorqual whales are the blue whale, Bryde’s whale, sei whale, humpback whale and minke whale.
Adult finback whales can reach an average size of 60 feet and weigh close to 50 tons. This leviathan is second in size and weight only to the blue whale who holds the distinction of being the largest animal that has ever lived on planet Earth. And finbacks can be 7 to 8 times heavier than the largest and heaviest land animal, the male African elephant. But like elephants and other highly evolved mammals, scientists believe that the finback whale and other large baleen whales have life spans of about 60 to 70 years.
Finback whales have a streamlined and muscular body that is built for speed. They are one of the fastest swimmers in the ocean and have been given the nickname, “the greyhound of the sea”. These animals can reach bursts of speed up to 35 miles per hour, but they cannot maintain these speeds over long distances, so this aquatic sprinter typically cruises at a more reasonable speed of just under 15 miles per hour.
Finback whales are found in all oceans of the world. In the spring, summer and fall, they feed in more northern and colder waters. In the winter, it is believed that finback whales migrate south to more tropical waters. In these
warmer waters, the females will give birth to their young and the other animals will breed or mate. However, a few hardy animals will over-winter, staying to feed in our rich and productive waters.
Off New England, finbacks feed from March until November on small schooling fish and crustaceans that are abundant offshore. When filter feeding, finbacks strain their food from the water using the series of baleen plates that hang down from the upper jaw. Baleen is a flexible, yet durable material composed of the protein keratin, the same protein that makes up your hair and fingernails. Hundreds of baleen plates hand down from both the right and left side of the whale's upper jaw and they are arranged one behind the other like the teeth of a comb. This creates a thick, hairy matt that acts as an effective strainer.
Finbacks are called lunge feeders for they will lunge mouth open through water and bait. The whale will then close its mouth and push the water back out of the mouth through the hairs of the baleen plates. Fish or crustaceans caught on the exposed hairs of the baleen plates will then be swallowed. Finbacks have enormous appetites and can filter close to 1 to 2 tons of fish out of the water each day.
The scientific name of the finback whale is Balaenoptera physalus. The word physa refers to the animal’s very tall blow also called the spout. The blow is the visible breath of the whale created as the whale breathes out - exhales at the surface.
The blow of a finback whale can rise over 20 feet above the water’s surface. Although the blow will disappear after a few seconds, it is visible from great distances.
The finback whale has a number of common names including: finback, fin whale, common rorqual, fin-basked whale, finner, herring whale and razorback.
These names refer to the shape of the whale’s body. Most finback whales have a dorsal fin that is tall and pointed. The dorsal fin of an adult finback whale can be 2 feet tall! Yet the size and shape to this large fin does vary from one finback to the next. This variation helps scientists identify individual finback whales offshore.
By photographing the dorsal fin and other body features, scientists can track individual finback whales to learn more about where they go and what they do.
Even with all the technology that is available to scientists today, the wintering grounds of the finback whale remains a mystery. Locating these areas is important for it would allow scientists to protect these magnificent animals year round and in all areas of their range.
Finback whales are sleek and streamlined with a large dorsal fin on the back of the animal. Finback whales are dark gray on the upper part of the body and white on the lower part of the body. However, the right side of the animal is lighter in coloration than the left side. Also, the lower jaw on the right side of the body is pure white while the lower jaw on the left side is dark gray. The finback whale is the only whale that has this distinctive asymmetric coloration. Scientists still can not fully explain the function of this two-tone look. Perhaps this type of shading helps camouflage the whale so it can sneak up on large schools of fish before opening its mouth when feeding.
If you look closely at the right side of a finback whale, you will see a subtle pigmentation pattern near the head of the animal. These beautiful swirls of white and tan are called the blaze. The shape and pattern created by the blaze is unique for each finback whale. Scientists can use this feature along with the dorsal fin to help them identify and track individual finback whales sighted offshore.
Finback whales feed in northern waters where small schooling fish are abundant.
Finbacks 
eat many kinds of fish including herring, mackerel, capelin and sand lance. Occasionally they will feed on large zooplankton like copepods and krill that drifts in the ocean waters.
Finback whales are called rorquals for they have 50 to 100 throat grooves that expand when the animal is feeding. This helps to increases the size of the mouth and throat, allowing the whale to capture more food and water each time it lunges mouth open through the bait. After completing a lunge, the whale will spend a few minutes straining or pushing the water back out of the mouth through the hairs of the baleen plates. Once all the water is out of the mouth, the whale will swallow the bait.
Most finbacks feed for only 8 to 9 months each year! In the fall, finbacks begin their annual migration south to more tropical waters. In these warmer waters, finbacks will give birth to their young calves while others will mate or breed. Hard to imagine that a mammal of such immense size and weight can fast for months at a time, yet still have a very active lifestyle. Their secret? Blubber! Blubber is the fatty tissue that is under the skin that insulates the animals in our cold New England waters. And it is blubber that is used as an energy source to keep finbacks alive then they are fasting for months at a time.
Reproduction
In the winter, most baleen whales will migrate or travel south to warmer, more tropical waters. There, the pregnant females will give birth to their young and the other whales will breed or mate. Scientists have yet to locate the breeding and calving grounds of the finback whale. However, scientists believe that a finback whale must be over 5 years old and reach a length of 60 feet to reach sexual maturity, the age at which a female can have a calf of her own.
Females typically have one calf every third year. At birth, the calf is between 15 – 20 feet long and weighs close to 2 tons. 
When the calf is born, the mother gently pushes the calf up to the surface for its first breath of air.The calf will begin to nurse from the mother and will consume large amounts of milk each day. The calf will continue to nurse for 6 – 8 months and will reach a length of 30 to 40 feet when it begins to feed on its own - when it is weaned.
Finback calves stay very lose to their mothers for about a year. Mom must protect the calf from natural predators which are sharks and killer whales. And mom is responsible for teaching her calf everything it needs to know to survive. After this first year, the calf will leave the mother and be on its own. It is believed that many finback calves return to the same feeding areas that mom introduced them their first year of life. Being able to re-sight these young animals will help scientists learn more about the life of the finback whale.
Finback Whales and their environment
Finback whales have good eyesight, and they can see well above the water’s surface as well as below. However, finbacks and other marine animals rely more on sounds to communicate or sense their environment. This makes sense since sound travels farther and faster in water than it does in air.
The finback whale uses sound to communicate over great distances in the ocean. The finback possesses one of the deepest voices on earth and these low sounds can travel hundreds of miles beneath the water. These booming voices are too low for humans to hear. Therefore, we must use computers and recording equipment to record and play back these sounds in a way that we can hear them or see them on a computer screen.
Photo-Identification of Finback Whales
Finback whales - Balaenoptera physalus are the second largest whale in the world, reaching lengths of 70-90 feet for adults. They are one of the fastest baleen whales offshore and are often referred to as the “greyhounds of the ocean”. Like all whales, the body of the finback is darker on the top and lighter on the body. This is called “counter-shading” and it help to camouflage the animal in the water column. However, finbacks are the only baleen whale that has an asymmetry to their overall body coloration. The right side of the body is lighter than the left side of the body. The purpose of this asymmetry is not well understood, but it can be used to help identify individual finbacks within wild populations.
Individual finback whales can be photo-ID using a number of unique body features that vary from one individual to another. These features are typically visible when the whale is at the surface and therefore, can be photographed on a regular basis. Comparing these features allows researchers to create catalogs of known individuals that have been sighted offshore. Comparing new individuals to known animals in the catalog help researchers track individuals over the course of the season or from one season to the next.
Features Used
On the right side of a finback’s body are found areas lighter in coloration than on the left side include:
- a white lower jaw
- the blaze
- the chevron
The lower jaws
The right lower jaw of a finback whale is white while the left lower jaw is dark gray like the upper part of the animal’s body. The function of this asymmetry in jaw coloration is not well understood. However, it may help the whale concentrate bait within the water column. When feeding, finbacks often circle schools of fish in a clockwise direction, exposing the whale’s whiter right jaw to the fish. This may help to concentrate the bait prior to the whale lunging mouth open through the water and bait.
The blaze
On the right side of the head, each finback has a unique pigmentation pattern
made up
of creamy whites, yellows and grays that sweep towards the upper back. These beautiful, yet subtle, patterns begin at the right lower jaw and end at the upper back of the whale. These pigmentation patterns are unique from one finback to another. Therefore, photographs of the blaze can be used to help identify individual finbacks.
The chevron
The chevron is a separate pigmentation pattern 
that straddles the upper back of the finback forward of the dorsal fin. It is named after the army chevron, a v-shaped pattern that is an ancient heraldic symbol of honor. The chevron can also be photographed and used to help distinguish on finback whale from another.
In addition to the above mentioned variations other markings are also used.
- the dorsal fin
- scars and other markings
- other pigmentation patterns
The dorsal fin
The dorsal fin of an adult finback whale can be almost 2 feet tall. 
Each finback has a dorsal fin with a unique size and shape. There may be a cut or gouge out of the leading or trailing edge of the dorsal fin that is unique to that individual. And there may be scars visible on either the left side or the right side of the fin itself. These features can easily be photographed and used to help identify individual finbacks offshore.
Scars and other markings
Some finback whales have scars on their body that is evidence of being hit by a vessel.Prop scars on the animal’s upper back or flanks 
are visible signs of a close encounter with either a small or large boat. A few finbacks have been observed with one side of the flukes cut off, indicating an encounter with a large vessel. These scars can be used to help identify individual finbacks offshore.
“Tracks” named for the propeller scars on the animal’s right flank or side.
Other pigmentation patterns
Sometimes there are other types of pigmentation patterns that can be seen on the body of a finback whale. These patterns can be photographed and used for photo-ID purposes.
The nonuse of the ventral flukes of finbacks
Unlike humpback whales, researchers do not use the ventral flukes of finbacks for photo-identification purposes. This is because finback whales typically do not raise their flukes above the water’s surface as they prepare for a deep or terminal dive. Finbacks have less body fat or blubber as compared to humpback whales; therefore, they are not as positively buoyant.
When a finback prepares for a deep or terminal dive, the animal typically arches its back and submerges in a long rolling motion without lifting the flukes out of the water. Sometimes a finback will lift its flukes out of the water. These occasions are rare and are not helpful for photo-ID purposes since the ventral tail pattern of most finback whales is white.
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