Cuvier's Beaked Whale: Ziphius cavirostris
IUCN Status: Least Concern
Status and distribution summary:
Occurs in all major oceans of the world, including the Mediterranean Sea, but not cold waters. Strongly associated with deep oceanic canyons and seamounts in the Atlantic, Pacific and Indian Oceans. Considered of Least Concern because of wide global range and locally relatively high abundance, but little is known about the species' true population. At well studied parts of its range, including the southern Bay of Biscay, it appears to be quite common.
Not targeted by whalers, though some small scale local catch historically.
Appears to be vulnerable to loud sub-surface noise including military sonar, with several associated mass-strandings. Known to ingest plastics mistaken for prey.
Where is it seen:
Southern sector of Biscay, associated with the canyon edges, on the continental shelf slope, and occasionally over the abyssal plain.
Frequency of sightings:
Regularly recorded between March and September. Usually seen as singles, or in small groups.
Medium sized whale (adults 5.5-7m).
In regular surfacing they usually show the following features:
- Generally brown pelage, which lightens with age. Older males can be very heavily scarred (often parallel gouges from the pair of teeth at the front of the lower jaw acquired in dominance fights between rival males), and older animals have variable amounts of pale (to white) on the forward upper parts.
- The dorsal fin is set well back (2/3 towards tail) and small, falcate.
- Indistinct beak and gently sloping forehead, with indentation behind blow-hole
- Low bushy blow, not always noticable.
Normally undemonstrative, so may easily be missed, but does breach and sometimes repeatedly.
A low blow bushy is not always visible.
Deep dives for a long time (20-40 minutes).
At surface, breathes at 10-20 second intervals, when they exhibit a slow roll that often starts with the melon, and then the dorsal fin just before submerging. Arches steeply before deep diving.
In calm conditions, is seen to log with forward part of back exposed on surface.
- Minke Whale: is only slightly larger, but are usually blackish above, and lack any pale colouration on the frontal upper parts.
- Northern Bottlenose Whale: is slightly larger and has similar colouration, but they often surface with a lunge that reveals the strongly domed melon (forehead) and can create a distinct bow-wave, and have a more robust and visible blow. Ranges do overlap in Biscay although their feeding niches are different.
- Other beaked whales: all other beaked whales are significantly smaller and are very rare, but do pose an identification pitfall.