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Graeme Cresswell -
Carey Jernigan -
Hilary Moors -
Dylan Walker -
Hilary Moors -
Hillary Moors -
WDC/Regina Asmutis-Silvia -
WDC -
Hal Whitehead -
Stephen Maclean
Northern bottlenose whale
The friendly and curious disposition of the Northern bottlenose whale made it an easy target for Norwegian whalers in the 19th and 20th century, with over 65,000 whales being killed and many more struck and lost. Individuals would often remain by wounded companions, becoming targets themselves. They were targeted initially for their oil, a form of spermaceti oil that is found in their head, and later as pet food. The northern bottlenose whale is one of the most well-studied species in the family Ziphiidae and forms an anti-tropical species pair with the southern bottlenose whale.
The Northern bottlenose whale is a large, robust whale. A defining characteristic of this species is the large bulbous forehead, which becomes more pronounced in males and with age. The forehead is steep, and the stubby beak is well defined resembling the beak of several dolphin species. Two small conical teeth erupt at the tip of the lower jaw in males although these are not always seen outside of the jaw. It has small pointed flippers that fit into 'flipper pockets' when the animal is diving, and a pointed triangular or falcate dorsal fin set well back on the body. The flukes are broad with concave trailing edges and no notch. The body is chocolate or olive brown to grey in colour with the head lighter and the dorsal fin darker than the rest of the body. The underside and flanks are a paler, creamy colour, and in older animals, the body bears light linear scars and circular cookie cutter shark bite marks. Juveniles are darker with a more rounded beak and smaller melon. The Northern bottlenose whale may be confused with Sowerby's or Cuvier's beaked whale, but the distinct bulbous melon and differences in body colouration allows for proper identification.
Northern bottlenose whales are inquisitive and often approach boats, where they can remain for some time. They can be found in groups of between 4 and 20 individuals and although their social-structure is primarily fission-fusion, long-term relationships have been recorded amongst same-sex individuals. The major prey item is deep-water squid and dives of over 1,400m have been recorded with animals submerged for up to 2 hours at a time. A more typical dive lasts less than ten minutes. They can be fairly acrobatic and have been seen lobtailing and occasionally breaching. They are not thought to be highly migratory in nature and in some areas where they have been well-studied, e.g. the 'Gully' canyon off Nova Scotia, some populations are found to be resident to a relatively small area.
The Northern bottlenose whale can be found in the cooler waters of the North Atlantic Ocean, from New England and southern Greenland in the west and from the Strait of Gibraltar and Svalbard in the east. Commercial whaling drastically reduced their numbers in previous years and although no longer the target of such large-scale hunts, the species is still taken in small drive-hunts in the Faroe Islands. As with other beaked whales species, the northern bottlenose whale is believed to be susceptible to the effects of loud anthropogenic noise. Other threats include the ingestion of plastic bags and interactions with fisheries. It is not known whether increased strandings in recent years are related to population increases or anthropogenic factors. The IUCN categorises this species as 'Data Deficient.
