Ship strikes to whales are a growing concern worldwide and, for many species, pose a threat to their population recovery. Data from NMFS within the Greater Farallones and Cordell Bank National Marine Sanctuaries totaled 20 whales killed by ships from to , with an additional 10 that were injured and possibly killed. Actual numbers are likely higher since many strikes go undocumented.
Whales also have a tendency to sink rather than float or wash ashore where they are more apt to be found. Ship strikes could be at least 10 times higher than documented numbers. Endangered whales blue , fin , and humpback whales , as well as gray whales, are the most commonly killed whales by ship strikes.
Whales are slow to recover due, in part to their slow reproductive rate. This fact, coupled with the many man-made threats that whales still face, demonstrate our urgent need to help them. The health of their population has implications for the health our coastal ecosystems.
The fin whale is a large baleen whale. It is the second largest animal alive today - only the blue whale is larger. It may reach a length of up to 75 feet in the Northern Hemisphere and 85 feet in the Southern Hemisphere.
Adult females are larger than adult males. Fin whales can weigh up to 80 tons , pounds. It has a long, slender streamlined body that is primarily dark grey with a white underside.
The fin whale's head is flat and there is a distinctive grayish-white chevron marking on the back behind the head. Its V-shaped snout has a single dorsal ridge running down its middle.
Its mouth is also quite distinctive, with the right lower jaw lip white, in contrast to the black left lower jaw. Its upper right lip is often white while the left lips are dark. Such asymmetrical coloration is unique among whales. Instead of teeth, it has great plates of horny baleen which extend from the upper jaw. These are used to strain food from large mouthfuls of water. It has two blowholes and grooves on the throat and chest. The baleen plates are white on the right side while the baleen on the left side are alternately striped yellowish-white and bluish-gray to grayish-white.
The fin whale's blow is tall and columnar in shape. The dorsal fin is situated far back on the body and is tall and steeply angled. A ridge runs behind the dorsal fin. This and the shape and size of the dorsal fin allow researchers to identify and track individual whales.
Distribution and Habitat Fin whales live within all of the major oceans of the world, primarily in temperate and polar waters. Their migration patterns are poorly understood compared to some whale species, such as the humpback whale Megaptera novaeangliae. It appears that fin whales may follow a similar migration as humpbacks within the western North Atlantic Ocean, feeding during spring, summer, and fall in northern latitudes and then spending the winter in the West Indies.
Summer feeding habitat is within cold waters where prey is abundant. Winter breeding and calving habitat is poorly understood for this species. Similar to humpback whales, it may be within warm subtropical or tropical waters.
Their prey is largely absent from these waters which would require fin whales to go without any food during the months spent at the breeding grounds. Fin whales primarily feed on tiny crustaceans known as krill as well as small schooling fish such as herring, capelin, and sand lance.
They feed by filter feeding with their mouthful of baleen. They do so by taking a large mouthful of both prey and water, closing their mouth, and then pushing the water out of their mouth using their enormous tongue. The prey items are then left within the mouth, trapped by the strips of baleen, and ready to be swallowed.
Fin whales may often be seen feeding within groups of individuals. In the North Atlantic Ocean, they will also be seen feeding near other species of whale, such as the humpback, and dolphins.
Truly handsome individuals, fin whales have long, slender bodies that can grow up to a whopping 80 feet in length. Like other baleen whales, fin whales have expandable pleats that allow them to take in huge amounts of water and food. They then sieve the water out through their baleen plates before ingesting their delicious meal, consuming up to 2,kg of krill in a day. Mostly sporting grey, dark brown and black tones with a gorgeous pale belly, from a distance there might not seem anything unusual about fin whales.
However, on closer inspection they have one very striking feature. Whilst on their left side their lower jaw is black, on the right side it is a brilliant white. Some scientists believe this unusual characteristic may have something to do with hunting strategies, although nothing is certain. Generally found alone or in pairs, fin whales are mostly solitary and are rarely found in groups.
Unlike other whales, fin whales are not too fond of the spotlight. They only rarely breach or spyhop, even avoiding raising their fluke out of the water for much of the time. Despite their seeming shyness, fin whales have no qualms when it comes to mixing with some other species of whales and have even been known to breed with blue whales, giving birth to hybrid calves!
On the whole, life for fin whales has been particularly hard. Relentlessly hunted for their oil, meat and baleen, their numbers have been radically reduced by whalers, though in the earlier days of whaling they were often too fast to be caught by the whale boats. These days, the struggle is ongoing, and the dangers of whaling industries are a constant threat. Despite recognising their vulnerable status, some whalers continue to target fin whales. Fin whales have a pretty simple diet, consisting of krill, small fish and crustaceans.
However, when you are that big and your prey is that small, you have to eat a lot to survive. In order to get their fill, fin whales can spend several hours each day feeding, gulping up to 70 cubic metres of water in one go before it sieving out.
With such big tummies to fill, fin whales can consume up to kg of krill every day. Most at home in the deep, open ocean, they prefer cooler waters and are rarely found in tropical waters. Like other large whales, fin whales are thought to migrate between feeding and breeding grounds.
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