Shepherd's beaked whale

Adults can reach lengths of 6 m (20 ft) to 7.1 m (23 ft) and weigh about 2.32 to 3.48 tons. At birth they may be about 3 m (9.8 ft) long. The longest recorded lengths were 7 m (23 ft) for a male and 6.6 m (22 ft) for a female.^[5]

They are robust and large-bodied for beaked whales, having a bluff melon and a long, dolphin-like beak.^[6]

It is the only species of ziphiid with a full set of functional teeth (17 to 27 pairs in both the upper and lower jaws).^[4] Adult males also have a pair of tusks at the tip of the lower jaw.^{[citation needed]}

They are dark brown dorsally and cream-colored ventrally, with a pale blaze extending up from the flipper and another pale area extending as a swathe on the posterior flank. The tall, falcate dorsal fin is set about two-thirds the way along the back.^[6] The width of the blaze varies for each individual, similar to the saddle patches of killer whales, which could also be useful for individual-level recognition.^[7]

Sightings and stranding records indicate that the species has a circumpolar distribution in southern hemisphere.^[8] No population estimates exist for Shepherd's beaked whale. As of 2006, there have been about 42 stranding records of the species from New Zealand (including the Chatham Islands, 24), Argentina (7), Tristan da Cunha (6), Australia (3), and the Juan Fernández Islands (2). The northernmost record was at Shark Bay in Western Australia in 2008.^[9] There have been five unconfirmed sightings (mostly from New Zealand), as well as a "probable" sighting near Shag Rocks and four confirmed sightings—the first two confirmed sightings occurred in 1985, within a few minutes of each other, off the Tristan da Cunha group (first sighting at 37°18′S 12°32′W); the third in 2002 near Gough Island (40°19′S 9°53′W); and the fourth in 2004 south of Tasmania (48°50′S 150°06′E).^[10] In January 2012, a group of up to a dozen of this species were photographed and filmed by the Australian Antarctic Division south of Portland, Victoria.^[11]

An adult photographed surfacing aerially in the Great Australian Bight (2012)

Multiple sightings of the species have been reported from Otago submarine canyons off Otago coast, New Zealand. Sightings have been recorded throughout the year with vocalization recordings, suggesting regular presences there.^[12] These include at least two sightings in 2016 which were the first confirmed sightings within New Zealand waters,^[13] followed by four sightings in 2017,^[14][15] one or more sighting(s) in 2018,^[16][17] one sighting in 2019,^[18] four or five sightings in 2021,^{[19][20][21][22][23]} five sightings in 2022 including a pod of 15-20 animals.^{[12][24][25][26]}

There have been additional sightings from other parts of New Zealand, such as off Gisborne,^[27] several sightings off Kaikōura,^[28][29][30] off Fiordland,^[31] Taranaki,^[32] and so on. The species is seldom seen because of its deep, offshore distribution in waters where sighting conditions can be difficult (the "Roaring Forties" and "Furious Fifties").^[10]

There are no reports of this species being hunted or killed accidentally by humans. Shepherd's beaked whale is covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MOU).^[39] Plastic debris and longline hooks have been found in the stomachs and intestines of some individuals, which could lead to internal trauma or starvation if the material blocks their digestive tracts.^[35]

Recent molecular evidence suggests that this species diverged after the most basal extant ziphiid genus, Berardius, and prior to Ziphius.^[40]

The species was featured on a 45p commemorative stamp issued by Tristan da Cunha in 2019 as part of a set celebrating different species of whale.^[41]

• List of cetaceans