CUVIER'S OR GOOSE-BEAKED WHALE
Ziphius cavirostris G. Cuvier 1823

Order Cetacea : Ziphiidae

DESCRIPTION. A moderately small-beaked whale with upperparts ranging in color from dark brown to lead gray or blackish; underparts paler but not whitish; occasionally head and upper back whitish. Beak moderately prominent and the forehead rising rather sharply; lower jaw longer than upper; pectoral fin relatively small, and the dorsal fin placed on posterior third of body; prominent keel extends from dorsal fin to tail; length of rostrum less than twice its breadth at notch. Lower jaw of males with one large tooth (about 7 cm in length and 4 cm in diameter) at the tip; in females, the teeth are small and seldom break through the gums, so the animal appears to be toothless; two converging grooves on throat. Total length of adults, 5–7 m. Weight, 2.5–4.5 metric tons.

DISTRIBUTION. Cuvier's beaked whales are found in all tropical and temperate waters around the world. Several strandings and sightings have been reported in the northern Gulf of Mexico, and this is considered the most abundant of the ziphiid whales in the region. The most recent stranding records for Texas (2002–2014) included one stranding of Cuvier's beaked whale, a female that washed ashore in Calhoun County on 25 October 2004.

SUBSPECIES. Monotypic species.

HABITS. Little is known of this whale beyond information revealed by stranded specimens. They are often observed in groups of 10–25. These whales are deep divers and may remain below water for over 30 minutes. They are known to eat squid, fish, crabs, and starfish.

The reproductive habits are almost unknown. There does not seem to be a distinct breeding season, as calves are born year-round. Calves are about 2.1 m long at birth. The length of gestation is unknown.

POPULATION STATUS. Rare; strandings and observations. There have been 19 stranding records, mostly from the eastern part of the Gulf, with very few from Texas. During the GulfCet surveys, Cuvier's beaked whales were seen 10 times from ships and 4 times from the air. These sightings were in the deepest part of the northwestern Gulf in waters 1,000 to 2,000 m (3,281–6,562 ft.) deep.

CONSERVATION STATUS. Cuvier's beaded whale is listed as threatened on the TPWD list but not by the USFWS. The IUCN status is given as least concern because of the species' large global range and relatively high abundance even with possible declines from localized threats. Given the paucity of information about the life history and occurrence of this species in the Gulf, there seems to be little justification for listing it as a species of concern. Stranding records are rare along the Texas coast, which is probably why TPWD listed the species as it did.

 

From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016.  Courtesy of the University of Texas Press.