Search

The article offers information on topics related to beaked whales. Topics mentioned include the rostrum deformities of whales, its behavior, and the species diversity of whales. Topics mentioned include the health management of marine mammals, the stranded northern bottlenose whale, and the causes of deformities in whales including acquired malformations, predation, and competition.

The article presents a critique of the article "Captive killer whale (orcinus orca) survival" by Jett and Ventre. The critic declares inappropriate the inclusion of data of stranded animals without information on the nature of stranding nor the health of the animal postranding, the direct comparison between captive and wild animal survival, and the comparisons of age-specific population survivorship using visual estimation of Kaplan-Meier curves.

On 16 June 1979, a herd of 41 sperm whales stranded near the mouth of the Siuslaw River in Florence, Oregon. The stomach contents from 32 whales were collected, identified to the lowest taxonomic level possible, enumerated, and measured. A total of 20,247 cephalopod lower beaks that represented 24 species from 14 different families were recovered. The most numerous species were Histioteuthis hoylei (25.9%), Taonius borealis (12.9%), Galiteuthis phyllura (11.2%), Gonatopsis/ Berryteuthis type (10.9%), and Moroteuthis robusta (10.7%). Reconstructed estimates of mass indicated that M. robusta contributed almost 50% of the total mass of cephalopods consumed, followed by H. hoylei (19.3%), and T. borealis (7.0%). The most important species in the diet of stranded whales were M. robusta, H. hoylei, T. borealis, G. phyllura, Octopoteuthis deletron, and Gonatopsis/Berryteuthis type. There were significant differences in the diet of males and females, but no differences between sperm whales of different age groups. Overall, sperm whales primarily consumed small cephalopods that were likely eaten south of 45ºN in or near the California Current System. This study provides new estimates of the food habits of sperm whales in the northeast Pacific from one of the largest strandings of this species. [ABSTRACT FROM AUTHOR]

Killer whales ( Orcinus orca) are widely distributed throughout the world's oceans, yet little has been documented about their stranding patterns. Knowledge of stranding patterns improves our ability to examine and sample carcasses and provides a foundation for understanding killer whale natural history, diet, reproduction, anthropogenic stressors, emerging diseases, and patterns of unusual mortality. We compiled published and unpublished killer whale stranding data to describe stranding patterns in the North Pacific Ocean. Between 1925 and 2011, 371 stranded killer whales were reported in Japan (20.4%), Russia (3.5%), Alaska (32.0%), British Columbia (27.4%), Washington (4.0%), Oregon (2.7%), California (5.1%), Mexico (3.8%), and Hawaii (0.8%). Strandings occurred at all times of year, but regionally specific seasonal differences were observed. Mortality and annual census data from Northern and Southern Resident populations were extrapolated to estimate that across the North Pacific, an average of 48 killer whales die annually. However, over the last two decades, an average of only 10 killer whale carcasses were recovered annually in this ocean, making each event a rare opportunity for study. Publication of a standardized killer whale necropsy protocol and dedicated funding facilitated the number of complete postmortem necropsies performed on stranded killer whales from 1.6% to 32.2% annually. [ABSTRACT FROM AUTHOR]

The article explores the presence of the Longman's beaked whale, Indopacetus pacifus, in Maui, Hawaii based on a stranding and necropsy findings. It emphasizes that the presence of such whale is confirmed through genetic testing of the specimen. It mentions the detection of morbillivirus infection in the species. It also notes the role of encephalitis in the stranding if there is a neurological dysfunction in the whale.

The article presents a study which investigates the increased behavior of beaked whales (BW) in Aleutian Islands, Alaska due to several mass strandings that have been linked to military sonar exercises. It mentions that the study deployed a high-frequency acoustic recording package to BW. It notes that due to inaccessible and remote location of sea during much of the year, longterm autonomous acoustic monitoring may guide to further understanding of the ecology and behavior of beaked whales.

This study's objective was to investigate mandibular fractures in 50 short-finned pilot whales, Globicephala macrorhynchus, from two mass strandings. Based on current theories that this species is sexually dimorphic and polygynous, hypotheses were: (1) males should suffer more frequent or more substantial mandibular fractures than should females, and (2) fracture occurrence should increase with male reproductive maturity and potential correlates of maturity, such as age and length. Fractures were described and correlated with physical characteristics to infer possible explanations for injuries. Mandibular fractures were surprisingly common in males and females, being found in more than half of the animals examined (27/50, or 54% overall; 17/36 or 47% of females and 10/14 or 71% of males). Length was the only correlate of fracture presence; the proportion of animals showing evidence of fracture increased with length. These results offer some support to initial hypotheses, but there must be another set of consequences that contribute to mandibular fractures in females. A combination of intra- and interspecific interactions and life history characteristics may be responsible for fractures. Further research from a larger sample of this and other cetacean species are suggested to help elucidate both the causes and implications of mandibular fractures. [ABSTRACT FROM AUTHOR]

The article presents a study on the diet and diet composition of pygmy sperm whales stranded in Hawaiian waters. According to the study, the contribution of deep-water fish to the Hawaiian pygmy sperm whale was the same to that of South African whales. It states that the significant diet component of pygmy sperm whales were crustaceans. It presents cephalopods as the primary prey of the whale species.