Of all the Ziphiidae, Hyperoodon ampulatus is the most well-known and researched. It is closely related to H. planifrons, which inhabits the oceans of the southern hemisphere, and the two may have diverged only a few thousand years ago. Both species are very similar in external appearance, with H. ampullatus being slightly larger. The two species can be differentiated based on geographic distribution and the flatter maxillary crests of H. planifrons (Collete Hendricks 1997, Reeves 1993).
The early Miocene of Australia yields the first fossil evidence of Ziphiids, one of the most primitive families of whales (MacDonald 1987, Vaughn et al. 2000).
Perception Channels: tactile ; chemical
The IUCN relieved Hyperoodon ampullatus of its "vulnerable" listing in 1991, an currently lists it as "Lower Risk, subjec to continued conservation." COSEWIC (Committee on the Status of Endangered Wildlife in Canada) assigned the species to its "vulnerable" category in 1996. Though not listed under the U.S. Endangered Species Act, trade in northern bottlenose whales is restricted by CITES, the species is included in Appendix I. These whales have not been hunted commercially since 1973.
US Federal List: no special status
CITES: appendix i
IUCN Red List of Threatened Species: data deficient
The Northen bottlenose whale was hunted for centuries for the spermaceti oil contained in its head and as a souce of food for native peoples. Scottish, English, and Norwegian whalers hunted H. ampullatus commercially from the mid-1800's until 1973. Because of its behavior of approaching large vessels and defending injured group members, whalers found Northern bottlenose whales easy to hunt. This whale's behavior and the fact that the spermaceti oil contained in its head was of almost equal quality to that of the Sperm whale resulted in overhunting and gross reductions in Northern bottlenosed whale populations around the turn of the century (Bloch et al. 1996, Reeves et al. 1993).
Hyperoodon ampullatus feeds primarily on squid (e.g. Gonatus fabricii), although sea cucumbers (Holothuroidea), herring (Clupea harrengus), cuttlefish (Sepiidae), sea stars (Asteroidea), and other benthic invertebrates supplement the diet. Utilizing a feeding method similar to that of Physeter catodon (the sperm whale), northern bottlenose whales make deep, sustained dives to capture prey. Dives last up to 70min and diving depths range from 80 to 800m with a maximum recorded dive depth of 1453m. Breathing intervals of 10min are common between deep dives and individuals frequently resurface in close proximity to where a dive began (Herman 1980, Hooker and Baird 1999, Minasian et al. 1984, Reeves 1993, Walker 1975).
Animal Foods: fish; mollusks; aquatic crustaceans; other marine invertebrates
Primary Diet: carnivore (Molluscivore )
The range of Hyperoodon ampullatus (the northern bottlenose whale) extends from the polar ice of the North Atlantic southwest to Long Island Sound and southeast to the Cape Verde Islands.
Biogeographic Regions: atlantic ocean (Native )
H. ampullatus is most commonly found in waters at least 1000m deep and often forages at or near the north atlantic ice shelf in sheltered embayments during the spring and summer.
Habitat Regions: temperate ; polar ; saltwater or marine
Aquatic Biomes: pelagic ; coastal
Average lifespan
Status: wild: 37.0 years.
Individuals of this species can reach up to 9.8m in length, but most are around 6.7-7.6m at the age of sexual maturity (7-14 years). They are sexually dimorphic, with males being up to 25% larger than females. The size of individuals in the Gully population (off Nova Scotia) is believed to be some 0.7m shorter than that of other Northern bottlenose whales. Individual whales may live up to 37 years (Herman 1980, MacDonald 1987, Whitehead et al. 1997a).
Northern bottlenose whales are varied in color, ranging from greenish-brown to chocolate and gray. Individuals may be blotted with patches of grayish-white and coloration is generally lighter on the flanks and underbelly, fading to a white or cream color. Young calves are generally chocolate colored in appearance (Evans 1987, Tinker 1988).
The body is long, robust and cylindrical and the beak is short, resembling a bottle in shape. Both sexes have large, protruding melons that are often vertical anteriorly in older animals and turn yellowish-white with age in males. The melon of the female is not as prominent as that of the male.The posteriorly-curved dorsal fin is 30-38cm in height and is located at a distance of 1/3 the total body length from the tail. The tail fluke lacks a medial notch and the flippers are small and pointed (Minasian et al. 1984, Tinker 1988).
The dentition of the species is highly reduced, with males possessing one or occasionally two pairs of short teeth in the tip of the lower jaw. These teeth never erupt in females, may never fully erupt in males, and often fall out with age (Minasian et al. 1984).
Range mass: 5800 to 7500 kg.
Range length: 9.8 (high) m.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
The mating system of Hyperoodon ampullatus is believed to be polygynous, with a single mature male associating with a group of females during the mating season.
Mating System: polygynous
Females become sexually mature at a length of 6.7-7m (8-14 years) and males reach maturity at 7.3-7.6m (7-9 years) (Evans 1987, MacDonald 1987, Minasian et al. 1984).
Mating occurs in spring and early summer and calves are born from April to June. Data from the Gully population near Nova Scotia indicates that the mating and calving period for this population may be from June to August. The gestation period for all Northern bottlenose whales is around twelve months and females exhibit a calving interval of two to three years. (Whitehead et al. 1997a, MacDonald 1987, Reeves et al. 1993, Tinker 1988).
Breeding interval: Females exhibit a calving interval of two to three years
Breeding season: Mating occurs in spring and early summer
Average gestation period: 12 months.
Average weaning age: 12 months.
Range age at sexual or reproductive maturity (female): 8 to 14 years.
Range age at sexual or reproductive maturity (male): 7 to 9 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Average gestation period: 365 days.
Average number of offspring: 1.
Calves are around 3.5m in length at birth and weaning occurs at around one year of age.
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
