Pod Of Whales Research Articles

“Orgy of Blood” vs “Getting Food on the Table”

The Faroese grindadráp is a centuries-old, dramatic spectacle in which an entire pod of pilot whales is slaughtered en masse in a blood-soaked harbour, followed by the distribution of whale meat and blubber to participating villagers. For many Faroese, grindadráp is an embodiment of nationalism, achieved through the primordialization of tradition and the securitization of a beloved food source. For many outsiders, particularly since aggressive anti-whaling campaigns have besmirched the Faroese reputation in the international gaze, grindadráp amounts to a barbarous anachronism intolerable in modern society. This study takes a multivocal digital ethnographic approach to explore how politics, economics, and ethics of grindadráp are understood through social media debates, institutional rhetoric, and an interview. It considers how essentializing discourses of tradition and modernity are framed, their implications for collective action, and some potentialities that are revealed through a shift in perspective from barbaric ritual to dynamic economic practice.

Call discrimination for an unknown pod of killer whales (Orcinus orca) in the Eastern Canadian Arctic

Killer whales produce pulsed calls, which are used for communication. Calls are highly stereotyped, and repertoires are unique to individual pods. Discrimination amongst these calls and comparison of call repertoires between pods can help determine population structure in killer whales and can be used to track pod movements. Calls were detected in underwater acoustic recordings from August to September 2017 in the waters near the community of Pond Inlet, Nunavut, Canada. Eight stereotypic call types were identified using whistle contour extraction and network analysis to compare contours. We present a repertoire of killer whale calls recorded. The potential for increased killer whale presence and magnitude of predation on narwhals is a source of concern for management of the population and by Inuit subsistence hunters who rely on narwhals for food and economic benefit. Describing the acoustic repertoire of killer whales seasonally present in the Canadian Arctic may help identify the stock or pod and determine their seasonal movements. Comparisons of this repertoire with killer whale calls from other Atlantic pods has not yet yielded a match. However, the results presented may provide a basis for future comparisons and aid in identifying killer whale ecotypes making seasonal incursions into Arctic waters.

Whale-Watching Activity in Bahía Málaga, on the Pacific Coast of Colombia, and its Effect on Humpback Whale (Megaptera Novaeangliae) Behavior

During the whale-watching season of 2008, 6,663 whale watchers and 267 boat trips were recorded in Bahía Málaga, Colombia. Forty-four percent of humpback whale pods sighted in the area were approached by boats. Operators in 2008 did not comply with Colombian whale-watching guidelines during most encounters. The modal distance between whales and boats was 50 m. Ninety-four percent of boats approached too fast (>3 knots), and 78.6% of them approached mother–calf pods. On average, a pod of whales was observed for 42.6 minutes (SD 33.1), and by more than one boat in 60.2% of cases. As a consequence of boats' presence, whales modified their behavior by reducing blows per minute, moved faster and more erratically, increased breaching frequency, and decreased resting behavior.

Behaviour of Short-finned Pilot Whales Globicephala macrorhynchus (Gray, 1846) (Mammalia: Cetartiodactyla: Delphinidae) in the southeastern Arabian Sea

We report the presence and behaviour of a pod of short-finned pilot whale Globicephala macrorhynchus in the southeastern Arabian Sea. The pod was observed in the southeastern side of Minicoy Island, in the Nine degree channel (09°219′23′′N;74°39′529′′E) on 03.02.2013. Later, on 06.02.2013,the same pod of pilot whales were observed near Kalpeni Island (10°02′402′′N; 73°39′579′′E) 130 km northwest of the previous location. The average length of the whales was estimated as 550 cm and weight as approximately 1200 kg. They were travelling in a northwesterly direction. The pod size of the whales sighted was twelve and several species specific behaviour such as side rolling, spyhopping, lobtailing, peduncle arching and movement patterns such as synchronous travelling and logging could be observed. The occurrence of scars and injuries on the body of four whales in the pod are also reported.

Prey switching by killer whales in the north-east Atlantic: observational evidence and experimental insights

Studies in the Pacific have identified distinct killer whale ecotypes that are either specialized mammal- or fish-eaters. The different types have developed hunting strategies that would suggest specialization could be more advantageous than generalism. However, it has been suggested, based on long-term dietary markers of tooth wear and stable isotope values, that lineages in the North Atlantic are generalist, but with individual variation in the proportion of prey types consumed. Here, we present the results of ten years of observational and photo-identification data of a population of killer whales that follows the Norwegian spring-spawning stock of Atlantic herring. Although the whales were predominantly observed while feeding upon herring, one pod of herring-eating whales was also observed interacting with seals. This supports the hypothesis based on the long-term markers, of a degree of specialization, with a small number of groups persistently feeding upon mammals, but switching between herring and seals. We further investigated this prey switching by conducting playbacks of herring-eating killer whale sounds to harbour seals at haul-out sites on the herring spawning grounds. We recorded changes in behaviour consistent with an anti-predator response, suggesting the seals perceived the herring-eating killer whales as a potential predatory threat and had not habituated to their calls. This could be due to the risk of herring-eating killer whales switching to mammalian prey, or the difficulty of discriminating between killer whale pods due to the large population size and number of killer whale call dialects in this population, or a combination of both.

Pussycat, Pussycat, Where Have You Been? by D. Bar-el & R. Maté

Bar-el, Dan, and Rae Maté. Pussycat, Pussycat, Where Have You Been? Vancouver: Simply Read Books, 2011. Print. In this superbly illustrated book, the pussycat of the classic nursery rhyme continues from his royal visit in London on to more distant and exotic adventures. He sails down the Seine in France, visits with “one of a kind” animals in Australia, kayaks with a pod of whales in the North, and discovers the mysteries of the Egyptian pyramids. North American geography is subtly evoked as he meets a fisherman in a coastal community and takes shelter from a Prairie thunderstorm in a “soft golden” wheat field. Many elements of the book convey nostalgia and the simple joys of childhood. It features a storybook-like font and extra-large capital letters at the beginning of each stanza. The hand-painted illustrations are magnificent and have a vintage fairy-tale like appeal. However, the complexity of the ideas conveyed in the simple rhyme scheme hints at more mature life lessons and ideas. For example, when the Pussycat encounters a parade of pageant performers, his owner asks, “Did you join in?” he responds with: “If life is a circus/ Why wait to begin?” The sense of adventure is tempered with reality; he is, on occasion, fearful, sad, or in need of assistance in his travels. He always reveals to the reader what helped him through those times: “What stopped your sorrow?” “I sang to the stars as I rode to tomorrow”. He also explains that he was able to take the “road less travelled” due to the generosity of fellow travelers: ‘…Did you get lost?’‘I strayed from the pathAt whatever the cost.’‘Pussycat, PussycatBut were you alright?’‘The kindness of strangersGave warmth to my night.’ Pussycat also talks about missing loved ones back home, in this case his owner. The adventure concludes with him inviting her to join him on his next series of imaginary adventures: “Come travel with me/ My partner, my friend.” According to the publisher’s website, this book is recommended for ages to 4-8. It would be an excellent addition to any home, library, or school book collection. Highly recommended: 4 out of 4 starsReviewer: Kim Frail Kim is a Public Services Librarian at the H.T. Coutts Education Library at the University of Alberta. Children’s literature is a big part of her world at work and at home. She also enjoys gardening, renovating and keeping up with her two-year old.

Age-dependent accumulation of heavy metals in a pod of killer whales ( Orcinus orca) stranded in the northern area of Japan

Mercury (Hg), cadmium (Cd), iron (Fe) manganese (Mn), zinc (Zn) and copper (Cu) concentrations in the liver, kidney and muscle of nine killer whales (including three calves) that stranded together in the northern area of Japan were determined. The Hg and Cd concentrations were found at trace levels in the calf organs, and increased with age. The Fe concentration in the muscle was significantly lower in the calves than in the mature whales and also increased with age. In contrast, Mn and Cu concentrations in the muscle were significantly higher in the calves than in the mature whales, and changes in the Zn concentration relative to age were unclear. These results suggest minimal mother-to-calf transfer of the toxic metals Hg and Cd and accumulation of these metals in the organs with age, while the essential metals Mn and Cu were found at higher concentrations in the muscle of calves than in mature whales.

Distribution of total mercury, methyl mercury and selenium in pod of killer whales (Orcinus Orca) stranded in the northern area of Japan: Comparison of mature females with calves

Total mercury (T-Hg) and selenium (Se) concentrations in liver, kidney and muscle from a pod of killer whales including five mature females and three calves stranded in the northern area of Japan were analyzed. In the mature female, contamination level of T-Hg in the liver sample (62.2±21.9μg/wet g) was markedly higher than that in kidney sample and muscle sample. The molar ratio of T-Hg to Se in the liver sample was approximately 1, and those in the kidney and muscle samples were markedly lower than 1. These results suggest that the formation of HgSe compound increases the hepatic accumulation of mercury (Hg). In contrast, contamination level of T-Hg in the calf organs was much lower than that in the mature female organs. These results suggest that the transfer of Hg from the mother to the fetus via placenta and/or to calf via milk is trace.

Analysis of frequency structure of sperm whale clicks as a function of dive depth and animal orientation

During overnight tracking of a pod of sperm whales in the Gulf of Mexico in July 2000, the NOAA ship GORDON GUNTER recorded their characteristic ‘‘click’’ sounds on a five-element towed hydrophone array. Multiple reflections from the surface and ocean bottom were also recorded. Analysis of the arrival times and bearings of the reflections allowed the computation of three dimensional dive profiles for several animals. By assuming the orientation of the animal was aligned with its velocity, the relative orientation of the animals relative to the array could also be estimated. A visual examination of the frequency content of the received clicks versus dive time suggested that the double resonances in the 1.2 and 2.2 kHz band increased 20%–30% during depth changes of 1000 m. In this presentation the possible relationship between click structure and whale depth and orientation is rigorously analyzed, and the observed relationships are compared with predictions from various sound production and resonator models, in an attempt to gain insight into the sound production mechanism. [Work supported by Minerals Management Service, National Marine Fisheries Service, and ONR.]

Within-pod variation in the sound production of a pod of killer whales, Orcinus orca

Pod-specific calling behaviour of resident killer whales has been shown to include: discrete call types not shared among pods, different production rates of shared call types, and differences in the detailed structure of shared call types. To investigate the mechanisms leading to pod-specific calling, we compared the repertoire and structure of calls produced by three different matrilineal units within the same pod, and described call features encoding matrilineal-unit distinctiveness. The three matrilineal units had different production rates of shared calls, including one call type used almost exclusively by one matrilineal unit. Cross-validated discriminant function analyses revealed matrilineal-unit distinctive structure in five of the six shared call types examined, with duration of the terminal component being the most distinctive feature for all call types containing a terminal component. Calls generally consist of low- and high-frequency components that may follow different time-frequency contours. In our sample, a particular high-frequency contour was consistently paired with a particular low-frequency contour, both contours had roughly equal overall variability, and each contained independent matrilineal-unit distinctive information. The only call type that did not differ structurally between matrilineal units is reportedly used more in interpod meetings than in intrapod contexts. The differences in calling behaviour between matrilineal units were similar in form to previously described differences between pods, although more subtle. These results suggest that pod-specific calling behaviour in resident killer whales arises primarily as a consequence of accumulated drift or divergence between highly cohesive matrilineal units as they gradually separate into different pods.

Three-dimensional localization of diving sperm whales using a short-aperture towed horizontal array

Three-dimensional sperm whale localizations are typically obtained via recording their ‘‘clicks’’ on widely distributed hydrophones. Here, an alternative 3D localization method is investigated, using data collected by an 8-m aperture, five-element horizontal towed array deployed from the NOAA ship Gordon Gunter in the Gulf of Mexico, as part of a recent sperm whale pilot study. During the night of 3 July 2000, the Gunter towed the array at a steady 1-kn speed and 60-m depth through a pod of sperm whales, in 1000-m-deep water. During that time, surface and bottom reflections from a single sperm whale click were often recorded. By measuring the bearings and relative arrival times of the direct arrival and reflections, the whale location, array depth, and array tilt could be computed. The latter results were checked against measurements obtained from a time-depth recorder attached to the array. Assuming that the speed of the ship remained fixed and the prevailing currents did not change, subsequent positions could then be obtained using only a surface reflection. This method may provide a convenient way for observing dive profiles of animals within a few kilometers of a survey ship. [Work supported by Minerals Management Service, National Marine Fisheries Service, and ONR.]

Response of gray whales to low-frequency sounds

One transducer from the U.S. Navy SURTASS-LFA source was used during January 1998 to expose migrating gray whales off the California coast to low-frequency sound. These transmissions were 42 s in duration, repeating every 6 min, and 160–330 Hz. The whales were observed from shore stations north and south of the source location. Each pod of whales’ closest point of approach (CPA) to the sound source was estimated from the shore observations. The received level (RL) at the CPA was estimated using measured transmission loss curves and the known source level. The probability of observing whale pods at each RL is computed under both playback and control conditions. The difference between these probabilities as a function of RL provides a measure of avoidance for the animals. Previous work [Malme et al. (1984)] found a 50% change in these probabilities at a RL of 120 dB re:1μPa. For an inshore source location, the current work found 50% avoidance occurred at a RL of 141 dB, with 95% confidence bounds of ±3 dB derived by bootstrap statistical methods. For the offshore source location, 50% avoidance was not achieved for any observed RL. [Work supported by ONR.]

Genetics for Wildlife Conservation

cott Baker maneuvered his rubber boat closer to a pod of humpback whales diving in the murky waters off Alaska's southeastern coast. As the boat drew within 20 feet or so, Baker reached for his crossbow and arrow. Carefully, he took aim at the nearest whale and fired. The arrow struck home-it's hard to miss a target the size of a humpback whale at close range, Baker admitsdriving the dart tip into the animal's side.

Observations during the stranding of one individual from a pod of Pilot Whales, Globicephala melaena, in Newfoundland

Observations during the stranding of one individual from a pod of Pilot Whales, Globicephala melaena, in Newfoundland

The Sperm Whale and its Food

OUR fund of accurate knowledge of the Cetacea being at so low a level, it is to be deplored that trained scientific observers have hitherto had few opportunities for noting under normal conditions the habits of these most interesting animals. And therefore naturalists generally will certainly hail with delight the news of the resolution of the Prince of Monaco to endeavour by all the means at his disposal to make an effective study of that least understood of all the deep sea mammalia—the great sperm whale. An observer like Dr. Scoresby who, while gaining his livelihood by the pursuit of the Greenland whale, lost no opportunity of studying that monster's manners and customs for the benefit of science generally, is still to seek for the world-wide fishery of the cachalot. This may be said without in the least minimising the excellent work done by Surgeons Beale and Bennett, who remain almost the only first-hand authorities we have on the sperm whale. They were not in command, and were consequently at a great disadvantage for making observations; for the whole crew of a whaleship are co-partners in the venture, and the essential business of oil-getting must on no account be hindered, or there is trouble all around. And since their day, unfortunately, British shipowners have had little or no interest in the southern whale fishery, while none who know what a motley crowd constitute the crews of American whalers, will be surprised that no contributions to natural history come from that quarter. I am the more pleased, therefore, that in the course of my career as a seaman, it happened that I was induced some twenty-one years ago to join a whaleship in New Zealand for a long cruise in the Southern and Eastern seas. All the average sailors' usual ignorance of the differing characteristics of different whales was mine; but so interesting did I find the study of these great denizens of the deep sea, under my extended acquaintance with them, that I seized every chance I could obtain to learn wrhatever I could of them, without any idea at the time of putting the knowledge so gained to any practical use. The first occasion worthy of note here was also my initial encounter with a cachalot. We were cruising the wide stretch of ocean in the South Pacific known as the “Vasquez” grounds, and sighted a small pod of sperm whales, mostly sprightly young cows, under the guardianship of two or three immense bulls. We lowered four boats, and very soon the boat in which I happened to be “fastened” a medium-sized cow, who promptly returned the compliment by rising bodily beneath the boat and ripping the bottom out of it with her hump. Of course our connection with that whale was at once severed, the task of keeping our heads above water, with our boat hardly more than a bundle of loose planks beneath us, being amply sufficient to occupy all our energies until we were rescued. In the meantime the second mate had successfully harpooned and slaughtered another and much larger whale very near to us—so near, in fact, that we weltered in a gory sea lashed into foam by the monster's dying struggles.