Fin Whale (Balaenoptera physalus) - Fin whales are characterized by asymmetrical coloration: they are dark on the right side of their throat and part of their chest; they are white on the left side. This species reaches 27 meters; the female is larger than the male. Its body is thin, its belly is white, and its back is usually dark. Dorsal fins measure 60 cm tall. They are found in oceans worldwide. They feed on pelagic crustaceans, codfish, and other fish. Their gestation period is 11 to 12 months. During the spring and summer, these whales remain in warm waters, while in autumn and winter they migrate to tropical waters to mate and give birth to their offspring. Usually, they travel in groups of 6 to 7 whales. They have sometimes been seen alone and in pairs. In Puerto Rico, they have been seen south of Ponce.
Sei Whale (Balaenoptera boreal) - This species exhibits considerable variations in coloring. Their backs vary from dark gray to black with bluish areas that spread to the sides. Their chest is lighter with pink tones. They measure between 14 and 18 meters; females are larger than males. Their body is elongated with a prominent dorsal fin that measures up to 60 cm tall. The head has a single ridge on top, and a gray right lower lip is characteristic of this species. It inhabits all seas especially in temperate areas, migrating to cooler areas during the summer to feed. They are usually found in groups of 2 to 5 individuals. It is possibly the fastest of the great whales, reaching speeds of approximately 30 miles per hour. Their food consists of small fish and crustaceans.
Bryde's Whale (Balaenoptera edeni) - This is one of the few mysticeti species that do not migrate to the poles in the summer. They mainly live in tropical and subtropical areas. Its head is elongated and has three ridges on top. The three ridges are positioned as follow: one in the center that reaches the blowhole and one on each side. They measure between 12 and 14 meters, and in general, females are larger than the males. Their body is elongated and thin, their back is dark-colored and their chest is lighter. They live in all tropical oceans including the Caribbean. Their food consists of sardines and anchovies. The gestation period is relatively longer than in other whales, almost a year.
Minke Whale (Balaenoptera acutorostrata) - This whale is one of the smallest in size among the mysticeti. The average size is 6 to 9 meters long. They are characterized by a diagonal stripe or a white spot on the pectoral fins. Their backs are black and their chests are white. Most live in temperate waters, specifically in the southern hemisphere or to the north of Antarctica. However, they have been sighted in the Caribbean and Puerto Rico, specifically in the Mona Passage and east of the Virgin Islands. They travel in groups of 2 to 3 whales and sometimes solitary animals have been seen. They feed on codfish, krill, and fish. Their gestation period is 10 to 11 months.
Humpback Whale (Megaptera novaeangliae) - The nodules on the head, long pectoral fins along with the patterns of white and black on the chest area are characteristic of the species. They vary in size from 12 to 16 meters; females are larger than males. They can reach a weight of 40 tons as adults. The body is robust and black; it becomes narrow past the hump and dorsal fin. Pectoral fins are a third of the total length of the body and are mostly white.
Humpback Whales migrate to our shores in late November and stay until the end of April in one of four sandbars in the area north of the Caribbean Sea. Two of these sandbars are located north of the Dominican Republic, one north of the Virgin Islands and the other one is close to the Borinquen sandbar between Aguadilla and Isabela. Many times, whales are seen traveling from one sandbar to another. These cetaceans have adjusted their migratory habits to take advantage of two completely different habitats and use them for different purposes: feeding and reproducing. The warm waters of New England and Canada serve these whales as feeding sites during the summer. They feed on small fish such as herring and eel. On the other hand, the tropical waters of the Caribbean serve the humpback as habitat during the winter (November to April) for mating and giving birth to their young.
Humpback Whales have acquired a high degree of brain development and this is seen in their social behavior. To communicate, humpbacks jump, splash their tail fin and pectoral fins and make a very complex sounds called songs. Males have the ability to produce these sounds in patterns, which are repeated over and over. That is why they are called songs, like bird songs. Unlike birds, humpback melodies are extremely long (6 to 30 minutes) and change from season to season. In the Borinquen sandbar, songs that were heard in the 1980s are different from those heard today. Also, songs heard in Puerto Rico are different from those by the same species in Hawaii. It is believed that the variety of songs in the same population helps females choose a male to mate with.
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