On an unidentified beaked whale found stranded in Kagoshima
25th Dec. 2002
National Science Museum, Tokyo
Kagoshima City Aquarium
University of Auckland (New Zealand)
A 6.5 m beaked whale was found stranded in Kagoshima-ken (prefecture) on the 26 th of July, 2002. We did not know any whale species from Japanese waters with this body size and external appearance. Species identification was made based on morphological and molecular biological characters. We came to a conclusion that the specimen is a female Longman's beaked whale.
A brief summary of our findings on the specimen is presented below. Investigations were made by National Science Museum, Kagoshima City Aquarium, Kanagawa University, Institute of Cetacean Research, Kyusyu University and University of Auckland. Investigations were supported by Sendai-shi, Kagoshima-ken and Uemura Gumi.
A bigger photo will appear with a click on a photo of the whale (not with illustrations).
1. Basic information
Found date: July 26. 2002, 10:45 a.m.
Locality: Nishikata beach, Sendai-shi (city), Kagoshima-ken (prefecture)
Species: Unidentified Ziphiid, Female, BL; 6.48m
2. Examination
Jul. 26. It was first reported as alive, but confirmed dead when examined by Kagoshima City Aquarium. The carcass was buried after a quick check including making external measurements and sampling stomach contents. It was tentatively identified as Baird's beaked whale (Berardius bairdii).
Examination of photos taken at the time of stranding made it clear that further examination of the specimen would be required to confirm its species identity.
Aug. 3. The carcass was dug up and major examinations were made. All the skeletal elements were collected. Samples for molecular biological analyses, contaminants analyses and so on were collected.
Examinations were made by National Science Museum Tokyo, Kagoshima City Aquarium, Kanagawa University, Institute of Cetacean Research, and Kyusyu University.
3. Findings
Body was spindle shaped with some lateral compression. Dorsal fin situates at about 70 % of the body length from the tip of upper jaw. Lengths of the flippers are about 10 % and the maximum width of the both flukes was about 20 % of the body length.
Head view
V-shaped Groove at throat
The beak is long and slender and smoothly continues to the melon. The melon is long and narrower than the bulge made by the skull. Cheek is rounded. V-shaped grooves are found at the throat. Probably only one pair of teeth were embedded at the tip of lower jaw. Unfortunately the right tooth was removed before our investigations. Tooth is about 40 mm in height and not erupted. Flipper shape is almost typical for those of ziphiids but a little slender with faint pocket. Dorsal fin is tall and triangular. Body color is light- to dark-gray in general with light brownish area around the beak and melon. Tail flukes lack median notch.
Body surface is heavily scarred with cookie-cutter shark bites fresh and old, especially around the ano-genital region. Numerous whale lice are found especially around fresh scars.
Lateral view of head Tip of beak
4. Systematic considerations
a. Based on the body shape, and position and shape of the dorsal fin, the flippers, and the flukes it is clear that the animal is of family Ziphiidae.
b. Known ziphiid species with the body length of 6 m or larger are:
Cuvier's beaked whale (Ziphius cavirostris)
Baird's beaked whale (Berardius bairdii)
Arnoux's beaked whale (Berardius arnuxii)
Northern bottlenose whale (Hyperoodon ampullatus)
Southern bottlenose whale (Hyperoodon planifrons)
Shepherd's beaked whale (Tasmacetus shepherdi)
Strap-toothed whale (Mesoplodon layardii)
The present specimen is different from any of the above-listed species in the shapes of body, head, and tooth,
c. Only possible species that can not be rejected is Longman's beaked whale (Indopacetus pacificus) known only from two skulls (Longman, 1926; Azzaroli, 1968), and the estimated body length based on the skull size of Indopacetus pacificuswas 25 feet (Longman, 1926).
5. Results
5-1 Skull morphology
The skull and mandibles of the Kagoshima specimen are extremely similar to those of the type specimen of Longman's beaked whale, based on the photographs and descriptions in Longman's original description (1926) and Azzaroli (1968).
5-2 Molecular biology
Whole genomic DNA was extracted from a skin sample taken from the specimen. Fragments of the mitochondrial DNA control region (D-loop) and cytochrome b were amplified using PCR. In phylogenetic comparisons, these DNA sequences grouped closely with those of the type specimen of Longman' s beaked whale to the exclusion of sequences from all other known beaked whale species (Dalebout, personal communication).
5-3 Stomach contents, etc.
Stomach contents collected on the first day were , beaks and lenses of cephalopods, nematodes possibly Anisakis sp. and several plastic debris. Ovaries collected at the secondary investigation were highly decomposed and no corpora lutea or albicantia were confirmed. Epiphises of thebones are all fused and the animal was physically mature. Some of the skeletal findings suggest that the animal was fairly old. No significant pathological findings were made because of the severe postmortem change.
Type specimen (Left) and the present specimen (right) Views of skull (right, upper, left and lower) and mandible Left tooth
6. Conclusion
The specimen in question was identified as Indopacetus pacificus(Moore, 1968). It is female and possibly senile.
Illustration based on photos and measurements By Yoshimi Watanabe
7. Further investigations
This is the final report for general readers. Further investigations will be made both in morphology and molecular biology. Results of the scientific examinations will be published in proper scientific journals.
Acknowledgements
We owe very much to Sendai City office, Kagoshima Prefectural Government and Uematsu Gumi in investigating the carcass, without help of which our investigations were impossible.
Note
1.
Reuter, BBC, NHK, etc. reported a possible stranding of Longman's beaked whale near Cape Town, South Africa on August 2002. As far as we could see from the images provided the whale is very similar to Cuvier's beaked whale. It is very unlikely that it was a Longman's beaked whale.
2.
The type specimen of this species is a beach washed skull found in 1882 and kept in Queensland Museum for a long time. In 1926 H.A. Longman, then director of the museum described this skull as a new species. Later in 1968, in his extensive review of the genus J.C. Moore put this species in newly established genus Indopacetus mainly based on the skulll morphology. In addition to the type, another broken skull found in Somalia has been known as the only specimens. There are some additional information of more specimens of this species, two from south Africa, one each from Maldives and Kenya. Present specimen is the World's 7th specimen and the only complete skeleton (Dalebout, peosonal communication).
3.
Skeletal preparation will be conducted by Kagoshiima City Aquarium and the mounted skeleton will be on exhibit in the future in the aquarium.
4.
Unidentified beaked whales possibly Longman's beaked whale were sighted by various researchers in various regions of the Indopacific (Pitman, et al., 1999; Pitman, 2002). Some of them could be the Longman's beaked whale, however, based on photos and witnesses' reports some were with a bulbous melon like bottlenose whale. There coulld be a possibility of anotther beaked whale species in the area.
References
Azzaroli, M.L.,
1968. Second specimen of Mesoplodon pacificus the rarest living beaked whale. Monitore Zoologico Italiano (n.s.) 2: 67-79
Longman, H.A.,
1926. New records of cetacea, with a list of Queensland species. Memoires of the Queensland Museum, 8: 266-278.
Dalebout, M.L.,
Ross, G. J. B., Baker, C. S., Anderson, R. C., Best, P. B., Cockcroft, V. G., Hinsz, H. L., Peddemors, V., and Pitman,R. L. (2003) Appearance, distribution and genetic distinctiveness of Longman's beaked whale, Indopacetus pacificus.Marine Mammal Science 19 (3) in press.
Mead, J.G.,
1989. Beaked whales of the genus Mesoplodon. Pages 349-430 in S.H.Ridgway and R. Harrison, eds. Handbook of Marine Mammals. Vol. 4. Academic Press, London.
Moore, J.C.,
1960. New records of the Gulf-Stream beaked whale, Mesoplodon gervaisi, and some taxonomic considerations. American Museum Novitates 1993:1-35.
Moore, J. C.,
1968. Relationships among the living genera of beaked whales, with classification, diagnoses and keys. Fieldiana: Zoology 53:206-298.
Pitman, R.L.,
2002. Alive and whale. A missing cetacean resurfaces in the topics. Natural History, 9: 32-36.
Pitman, R.L.,
D.M. Palacios, P.L.R. Brennan, K.C. Balcomb III, and T. Miyashita, 1999. Sightings and possible identity of a bottlenose whale in the tropical Indo-Pacific: Indopacetus pacificus? Marine Mammal Science, 15: 531-549.
For inquiries
Contact:
Tadasu K. YAMADA
Curator in Chief Section of Birds and Mammals
National Science Museum, Tokyo
Mail address: yamada@kahaku.go.jp
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