Whales of the North Atlantic

The gigantic blue whale is the largest animal ever to have lived on Earth. Adults often exceed twenty-five metres (eighty feet) long in the northern hemisphere, but record sizes of more than thirty metres (100 feet) have been measured further south. Their long columnar blows—humid air from their warm lungs that vaporizes as it expands in the colder air—can reach up to nine metres (thirty feet) in height.

Blue whales occur in small numbers within the estuary and northern Gulf of Saint Lawrence, in the Labrador Sea as far as the Davis Strait, and along both Greenland’s coasts to Iceland and Svalbard. Seeing them is a rare opportunity, but Adventure Canada expeditions have encountered them on a few occasions.

Blue whales are mysticetes (from the Greek for “mustached whales”), meaning that, instead of teeth, they have baleen plates in their mouth. They use these baleen plates to retain their prey while filtering out the sea water. Blue whales are feeding specialists that essentially only eat krill, a small schooling crustacean that form enormous swarms.

To capture their fill, blue whales rush a school of krill and suddenly open their mouths, gulping as many as they can along with the surrounding water. Their expandable throat bulges out to collect the lot and then retracts by pumping their tongue and filtering the seawater back out though the baleen plates.

The second largest animal that ever lived is another mysticete, the fin whale. In the North Atlantic, adults reach at least seventeen metres (fifty-six feet) long and some individuals may even measure twenty-four metres (seventy-eight feet). Their name comes from the prominent dorsal fin.

Another distinctive feature of a fin whale is the white colouration of the right-side of its lower jaw, sometimes seen when its head surfaces. The other side is grey like the rest of the body. This asymmetry may have evolved because these whales tend to attack their prey by lunging while rolling on their right side. Fin whales also have a dark grey back with many light grey streaks, particularly behind the blowhole.

Fin whales are seen in the summertime in the Saint Lawrence, off the coasts of Newfoundland and Nova Scotia, in the Labrador Sea, and on both coasts of south and central Greenland, as far east as Iceland and Svalbard. Fin whales take schooling fish, such as capelin and herring, but they also eat krill around Nova Scotia and Greenland.

Another mysticete, with some similarity to the fin whale, is the sei whale (sei means “pollock” in Norwegian). It is often confused at a distance, but there are subtle differences. Sei whales are more uniformly dark grey on the back and are smaller—adults reach less than sixteen metres (fifty-three feet) long and more often measure around fourteen metres (forty-six feet).

Sei whales also behave differently. Blue whales and fin whales surface bluntly and roll rapidly at the surface, showing their dorsal fin several seconds later and then arching their back to dive.

Sei whales appear more timid, often surfacing as if they had floated their whole body straight up to surface, showing their tall dorsal fin and blow at the same time, and later sinking below the surface in the same quiet manner. They are found in the same waters as fin and blue whales, although it is debatable if they enter the Gulf and estuary of the Saint Lawrence; it is possible that they are overlooked there because of their similarity to fin whales.

The smallest of the Balanopteridae family which includes the above species, the minke whale measures around 7.4 metres (twenty-four feet), with a few individuals reaching 8.8 metres (twenty-nine feet) in the North Atlantic.

This species is often seen feeding in bays and fjords on schooling prey species, such as capelin, sand lance, herring, squid, and krill, but can also feed on bottom species such as cod and redfish. It is very active when it feeds, projecting its head well above the surface to slap the water, presumably to scare the schooling prey into a tighter ball for ease of capture. The minke then lunges at the prey ball and engulfs as many of the prey as possible in its expanding throat, which looks pink during this vigorous activity due to dilated blood vessels.

The minke whale has a dark black back and a tall dorsal fin relative to body size. It rapidly surfaces, with an often-indistinct blow, immediately showing its tall dorsal fin at the same time. It often rolls rapidly at the surface and disappears just as quickly as it surfaced, leaving scorned observers with only the apt consolation, “Minke, minke, better not blinky.”

You are likely to see some in the Saint Lawrence, in coastal Nova Scotia, Newfoundland and Labrador, and along south and central Greenland. Occasionally, one may be spotted in the waters around south Baffin Island or in Hudson Strait.

The humpback whale is an oddball species compared to others in the Balanopteridae family of whales. Its long white pectoral fins (which measure up to five metres or sixteen feet) and knobby head are distinctive and unusual for this family. They often bound clear out of the water, in a behaviour called breaching, and slam their large bodies onto the surface with a great splash. They also like to slap their pectorals or tail fins at the surface, and, before diving, they invariably show their butterfly-like tail flukes. Because of these exuberant behaviours, they are the no-contest favourites of whale-watchers.

Adult humpback whales reach about thirteen to fifteen metres (forty-three to forty-nine feet) at maturity. Their small knobby dorsal fin sits upon a prominent hump—hence the name humpback! That hump makes them easily recognizable, even at a distance, when other cues are not visible.

Humpback whales are the most likely species to be seen, apart from minkes, in waters ranging from Atlantic Canada to Greenland, Iceland, and Svalbard. The larger members of the Balaenopteridae family severely declined in numbers in the previous century during industrial-scale commercial whaling. Although humpback numbers declined too, they have recovered faster because they give birth more frequently than other species.

In recent summers, the endangered North Atlantic right whale has begun to regularly occupy the Gulf of Saint Lawrence, a part of their ancestral range which they had not occupied much during the last century. Typically, the much-reduced population of right whales were better known for their summer inhabitancy in the waters off southern Nova Scotia, the Gulf of Maine, and the Bay of Fundy.

This whale’s western North Atlantic population has been reduced to only about 400 individuals—due to historical whaling up to the 1900s and more recently by ship strikes and fishing gear entanglements. When right whales are spotted in the Gulf, ships must sail at reduced speed to avoid striking a feeding whale, a time where they are most vulnerable to ship strikes.

These whales are recognized by their big black heads covered in light patches of rough skin, called callosities. Like the bowhead whale, its nearest relative, it lacks a dorsal fin on its otherwise black body. Right whales are filter feeders, feasting on small planktonic invertebrates that are suspended like clouds in the water column.

The Greenland right whale, more commonly known as the bowhead whale, is a truly Arctic whale, living amongst sea ice for most of the year. It is distinguished by its enormous and highly arched jaws. This enormous mouth contains the longest baleen plates of all species. Some of these plates can grow to three metres (ten feet) in length. These plates fray into delicate hairs on the tongue side and form a fine sieve on each side of the mouth, which allows them to skim their plankton prey while swimming slowly below the surface.

The bowhead whale has a distinct head silhouette and a black back with no dorsal fin. Adults measure about fifteen metres (fifty feet). Their back may show lighter coloured scars and, if you’re lucky to get close enough in calm water, you might see the white lower lip that some adults have.

Long-finned pilot whales are medium-sized whales, measuring between four to six metres (thirteen to twenty feet). They were originally called pilot whales because it was thought that each pod had a leader or pilot showing the way to the others when they entered coastal waters. Today in Newfoundland, pilot whales are often nicknamed potheads, blackfish, or squid-hounds, due to their prominent melon-shaped forehead, their black upper body, and their feeding habits.

Like belugas and narwhals, pilot whales are odontocetes, or toothed whales, different from the baleen whales discussed above. They are deep divers, ordinarily living on the continental slope, but also entering warm coastal waters in pursuit of large schools of their favourite prey, squid. On a summertime Adventure Canada expedition, you’re most likely to spot them in the waters around Newfoundland, Iceland, or the Faroe Islands.

If you are sailing along the coasts of Nova Scotia, Newfoundland and Labrador, or Baffin Island, you may be lucky to spot some northern bottlenose whales. These medium-sized whales are recognised by their uniform brown colour, their prominent foreheads, and their small sickle-shaped dorsal fins.

They are normally deep divers, feeding mainly on squid, though they also occasionally take herring and bottom fish. A few decades ago, an aggregation of northern bottlenose whales was found in a deep trench in the Scotian Shelf, some 200 kilometres off the coast of Nova Scotia. This trench is named The Gully and is now a Canadian Marine Protected Area, in part to protect this whale population.

Northern bottlenoses are often gregarious, surfacing in groups of two to ten whales, where they rest to recover from long dives. They are also fast swimmers and can easily outrun a ship at sea. They are known to seek out fishing boats in hopes of scoring some offal thrown overboard when the fishers clean their catch.