Stranding of a Cuvier's Beaked Whale in Victoria - 2nd June 2004.
A 6.15m long female Cuvier's Beaked Whale was beached alive on 2nd June 2004 at Sealers Cove on Wilson's Promontory, Victoria. Parks Victoria staff member Matt Hoskins called the Victorian Cetacean Stranding Network (VCSN) and a team was immediately mobilised, including staff and a vet from Melbourne Zoo, staff from Melbourne Aquarium and a crew from Wild Film TV (New Zealand), who generously assisted in the provision of a helicopter; Sealers Cove being a two hour walk from the nearest road.
The report, first received from a member of the public at Sealers Cove suggested that this animal entered the shallow bay with a calf, before beaching. The calf disappeared and was not subsequently seen. The whale was reported by Parks staff, to have died soon after hitting the beach at about 2:15pm. By the time that the VCSN team arrived at the site, the animal had been dead about three hours.
A full necropsy was undertaken but preliminary results indicated no obvious cause of death. Blubber thickness was 5cm (dorsal) and 4.1cm (ventral). The furthest anterior stomach was crammed full of squid beaks which have been deposited for identification with Mark Norman, a Cephalopod expert at Museum Victoria. Various material was collected for subsequent pathological examination. Biometrics recorded can be viewed here.
Particular thanks go to Esso Australia for providing veterinary equipment used in the necropsy, Natalie Rourke for giving up her time leading the necropsy, Wild Film TV for providing helicopter transport, Parks Victoria staff for their quick response and hospitality on site and the Australian Wildlife Health Network for assistance in funding analysis of samples taken.
Notes on why strandings occur
A preliminary analysis of material in the stomach shows that the animal was mainly eating squid. Many thanks to Mark Norman of Museum Victoria for the following information. Details are also taken from Mark's spectacular photographic guide 'Cephalopods A World Guide'.
Many of the smaller beaks from the Cuvier's stomach have not yet been determined to species, and this work is ongoing. Two of the beaks are of the gothic-looking and aptly named Vampyroteuthis infernalis or vampire squid, a species that is distributed world-wide and typically occurs at depths of between about 600-1,200m and is about 13cm long.
The very large beaks (several centimetre across) are from glass squid. Glass squid are a diverse group of very gelatinous squid that include some of the largest species to occur in the world's oceans. The group includes the "colossal squid" (Mesonychoteuthis), which is thought likely to exceed the weight of the giant squid (Architeuthis). A 6 metre long specimen was hauled aboard a fishing vessel in the Antarctic Ross Sea last year http://www.cephbase.utmb.edu/refdb/pdf/7551.pdf . This paper agrees with what we have observed so far that the diet of Cuvier's beaked whale is mainly oceanic cephalopods. Consistent with our observations, some authors have also found remains of crustaceans but also some oceanic fish, which we did not record.
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More information on Cuvier's beaked whales
IDENTIFICATION - Adapted from SEARCH Australian Whales and Dolphins, the Australian Petroleum Production Exploration Association's cetacean identification guide (Ross and Mustoe, 2004).
Among the largest and most distinct of the beaked whales. Compared with smaller species, it is more robust, broad and deep-bodied. As with most beaked whales, identification at sea may depend on good views of an adult male. Cuvier`s Beaked Whale does not have an obvious `beak`. Instead, the melon slopes down to a snout shaped somewhat like a `goose-beak` (giving this species its other common name, Goose-beaked Whale). Surfacing action is a significant identification character. Cuvier`s have been described as `lurching` out of the water then they seem to drop their head to plunge down before rolling. Colour may not be a useful identification feature as it can vary from blue-grey to brick red depending on the age of the animal and how active it is. The head and upper surface as far back as the dorsal fin become progressively whiter with age, while the flanks may darken. Older animals also accumulate scratches from fights with other males and oval scars resulting from attacks by cookie-cutter sharks. May form family groups, though older males are thought to live alone. The blow may be visible on calm days but is small and diffuse. As with other beaked whales, Cuvier`s Beaked Whales usually remain at the surface for a short time and dive for periods of between 30 minutes and an hour.
DISTRIBUTION AND STATUS
This most cosmopolitan of beaked whales is widely distributed in all regions other than polar waters, preferring deep water habitats. Present in tropical to sub-polar deep oceanic waters. A whale very likely to be Cuvier's beaked whale was seen in Bass Canyon about 100km away from the site of this stranding in January 2002 (Simon Mustoe, personal observation).
May concentrate along the 1000m contour or seaward of this contour. Could be locally common in any shelf-slope habitat in Australia. The most recent stranding of a Cuvier's in the wider region was Indonesia in October 2003. Cuvier's has stranded in all Australian states and Northern Territory, mainly between January and July. There have been strandings in Victoria at Mallacoota, (1964); 3km west of Cape Howe, (1987); and Griffith Island, (1994). The pattern of strandings may suggest some seasonal inshore movement, though it may also be resident in some areas.
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