Journal articles on the topic 'Cetacean'
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1
O'Leary, Maureen A., and Mark D. Uhen. "The time of origin of whales and the role of behavioral changes in the terrestrial-aquatic transition." Paleobiology 25, no. 4 (1999): 534–56. http://dx.doi.org/10.1017/s0094837300020376.
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Addition of the recently discovered fossil Nalacetus to a phylogenetic analysis of basicranial, cranial, dental, postcranial, and soft morphological characters reveals that it is the most basal cetacean, and that mesonychians form the monophyletic sister group to Cetacea. The molars of Nalacetus elucidate transformations in dental morphology that occurred early in the cetacean radiation and clarify certain derived differences in molar cusp position between cetaceans and the extinct clade, Mesonychia, hypothesized to be their sister taxon. Nalacetus and other archaic cetaceans share derived vertically elongate shearing facets on the lower molars. Applying the Extant Phylogenetic Bracket, we advance the hypothesis that these facets are an osteological correlate of aquatic predation. Our functional interpretation of this character and its distribution within Cetacea indicates that a behavioral change in tooth use characterized the origin of the clade. Comparison of the transformation of this dental character with that of the cetacean pelvis indicates that a change in tooth use (feeding behavior) occurred before loss of the ability to engage in terrestrial locomotion.The most parsimonious phylogenetic hypothesis presented here has a significant fit with the stratigraphic record as determined by the Manhattan Stratigraphic Measure, which is corroborated by retention indices of stratigraphic data. Ghost lineages necessitated by the phylogenetic hypothesis extend the stratigraphic range of Cetacea into the middle Paleocene (Torrejonian), ten million years earlier than the oldest cetacean fossil currently known. Primitive features of Nalacetus, the large number of synapomorphies diagnosing Cetacea, and the implied ghost lineage suggest that the early cetacean radiation was much more extensive than has been previously recognized.
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Werth, Alexander J. "Cetaceans as Exemplars of Evolution and Evolutionary Ecology: A Glossary." Oceans 1, no. 2 (May 25, 2020): 56–76. http://dx.doi.org/10.3390/oceans1020006.
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Extant cetaceans (whales, dolphins, and porpoises) and their extinct ancestors offer some of the strongest and best-known examples of macroevolutionary transition as well as microevolutionary adaptation. Unlike most reviews of cetacean evolution, which are intended to chronicle the timeline of cetacean ancestry, document the current knowledge of cetacean adaptations, or simply validate the brute fact of evolution, this review is instead intended to demonstrate how cetaceans fittingly illustrate hundreds of specific, detailed terms and concepts within evolutionary biology and evolutionary ecology. This review, arrayed in alphabetical glossary format, is not meant to offer an exhaustive listing of case studies or scholarly sources, but aims to show the breadth and depth of cetacean research studies supporting and investigating numerous evolutionary themes.
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Đuras, Martina, Ana Galov, Kim Korpes, Magdalena Kolenc, Matea Baburić, Andrea Gudan Kurilj, and Tomislav Gomerčić. "Cetacean mortality due to interactions with fisheries and marine litter ingestion in the Croatian part of the Adriatic Sea from 1990 to 2019." Veterinarski arhiv 91, no. 2 (April 15, 2021): 189–206. http://dx.doi.org/10.24099/vet.arhiv.1254.
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Various anthropogenic threats negatively influence the survival of cetaceans in all world seas. Thanks to a long-running marine mammal surveillance program, we are able to report the results of a detailed analysis of the influence of cetacean-fisheries interactions and marine litter ingestion on cetacean mortality in the Croatian part of the Adriatic Sea over the last three decades. The total number of dead cetaceans was 459, and included 334 bottlenose dolphins (Tursiops truncatus), 40 striped dolphins (Stenella coeruleoalba), ten Risso’s dolphins (Grampus griseus), six Cuvier’s beaked whales (Ziphius cavirostris) and four fin whales (Balaenoptera physalus). Three hundred of them were examined postmortally. Cetacean-fisheries interaction occurred frequently in the Adriatic Sea, being detected in 96 (20.9%) of the recorded cases. Bycatch was the most abundant cetacean-fisheries interaction, with 66 (14.4%) cases recorded. Good nutritional condition and evidence of recent feeding were the most common findings recorded in bycatch cases, followed by persistent froth in the airways, edematous lungs, bruises and an amputated fluke or tail. Cetacean-fisheries interactions other than bycatch affected 30 animals and included larynx strangulations, long-term tail entanglement and fishing gear in the stomach. Ingestion of marine litter that was not related to fisheries was recorded in four animals. This study reveals the considerable negative anthropogenic influence on cetaceans in the Adriatic Sea, especially the bottlenose dolphin that is considered to be the most numerous cetacean species therein, and demonstrates the need for the urgent development of a cetacean bycatch reduction program. Finally, it also shows the importance of sustaining national surveillance programs to gain scientifically based knowledge important for cetacean protection and prospects for their long-term survival.
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Purba, Andri Octapianus, IGB Sila Dharma, and Elok Faiqoh. "Sebaran dan Keanekaragaman Cetacea saat Musim Timur di Perairan Tejakula, Buleleng, Bali." Journal of Marine and Aquatic Sciences 6, no. 2 (December 4, 2020): 222. http://dx.doi.org/10.24843/jmas.2020.v06.i02.p9.
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Cetaceans are marine mammals whose entire life is in marine and fresh waters. Cetaceans consist of whales, dolphins, and porpois. The distribution of cetaceans is a matter that shows the points of emergence of cetaceans in a waters. Diversity index is to determine the diversity of a group by looking at the number of species in a group. The waters of Tejakula Subdistrict are one of the waters in North Bali. The waters of North Bali is one of the waters which has become a migration path for several species of cetaceans. As a cetacean migration pathway, there are many occurrences of cetaceans in the northern waters of Bali. One of the most famous locations for the emergence of cetaceans in Bali is the waters of the Tejakula District, so research on cetaceans in the waters of the Tejakula Subdistrict needs to be done. This study aims to determine the distribution and diversity of cetaceans in the waters of Tejaula District. This research was conducted for 3 months, namely in the months of July, August and September 2017. Research on the distribution of cetaceans was carried out to determine the cetacean emergence points. The types of cetaceans found during the three months of the study were Stenella longirostris, Stenella attenuata, Globicephala macrorhynchus, Steno bredanensis, Lagenodelphis hosei, and Grampus griseus. The diversity of cetaceans in the waters of the Tejakula sub-district in July was 0.55, August 1.24 and September 0.9. The cetacea diversity index in the study area was divided into two, namely the area outside the reserve 1.22 and the area in the reserve 0.55.
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Lynn, Spencer K., and Irene M. Pepperberg. "Culture: In the beak of the beholder?" Behavioral and Brain Sciences 24, no. 2 (April 2001): 341–42. http://dx.doi.org/10.1017/s0140525x01413963.
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We disagree with two of Rendell and Whitehead's assertions. Culture may be an ancestral characteristic of terrestrial cetacean ancestors; not derived via marine variability, modern cetacean mobility, or any living cetacean social structure. Furthermore, evidence for vocal behavior as culture, social stability, and cognitive ability, is richer in birds than Rendell and Whitehead portray and comparable to that of cetaceans and primates.
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Magalhães, FA, CH Tosi, RG Garri, S. Chellappa, and FL Silva. "Cetacean diversity on the Parnaiba Delta, Maranhão state, northeastern Brazil." Brazilian Journal of Biology 68, no. 3 (August 2008): 545–51. http://dx.doi.org/10.1590/s1519-69842008000300012.
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The increase in the research of cetacean surveys on the Brazilian coast has brought new data on the distribution of species never reported before. The present work reviews the current knowledge on cetaceans species and extends this knowledge with an analysis of cetaceans stranded in the Parnaiba Delta, on the coast of Maranhão State, Brazil. The studies on cetacean diversity on the coast of the Parnaíba Delta were made from August 2004 to August 2006. Fourteen strandings were reported, representing six distinct species, such as the estuarine dolphin (Sotalia guianensis), humpback whale (Megaptera novaeangliae), Bryde's whales (Balaenoptera edeni), dwarf minke whale (Balaenoptera acutorostrata), pigmy killer whale (Feresa attenuata), sperm whale (Physeter macrocephalus) and two specimens which have not yet been identified. The significant degree of cetacean diversity in the region shows that the Parnaíba Delta is, possibly, of an important area for cetacean studies in Brasil.
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McGowen, Michael R., Georgia Tsagkogeorga, Sandra Álvarez-Carretero, Mario dos Reis, Monika Struebig, Robert Deaville, Paul D. Jepson, et al. "Phylogenomic Resolution of the Cetacean Tree of Life Using Target Sequence Capture." Systematic Biology 69, no. 3 (October 21, 2019): 479–501. http://dx.doi.org/10.1093/sysbio/syz068.
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Abstract The evolution of cetaceans, from their early transition to an aquatic lifestyle to their subsequent diversification, has been the subject of numerous studies. However, although the higher-level relationships among cetacean families have been largely settled, several aspects of the systematics within these groups remain unresolved. Problematic clades include the oceanic dolphins (37 spp.), which have experienced a recent rapid radiation, and the beaked whales (22 spp.), which have not been investigated in detail using nuclear loci. The combined application of high-throughput sequencing with techniques that target specific genomic sequences provide a powerful means of rapidly generating large volumes of orthologous sequence data for use in phylogenomic studies. To elucidate the phylogenetic relationships within the Cetacea, we combined sequence capture with Illumina sequencing to generate data for $\sim $3200 protein-coding genes for 68 cetacean species and their close relatives including the pygmy hippopotamus. By combining data from $>$38,000 exons with existing sequences from 11 cetaceans and seven outgroup taxa, we produced the first comprehensive comparative genomic data set for cetaceans, spanning 6,527,596 aligned base pairs (bp) and 89 taxa. Phylogenetic trees reconstructed with maximum likelihood and Bayesian inference of concatenated loci, as well as with coalescence analyses of individual gene trees, produced mostly concordant and well-supported trees. Our results completely resolve the relationships among beaked whales as well as the contentious relationships among oceanic dolphins, especially the problematic subfamily Delphinidae. We carried out Bayesian estimation of species divergence times using MCMCTree and compared our complete data set to a subset of clocklike genes. Analyses using the complete data set consistently showed less variance in divergence times than the reduced data set. In addition, integration of new fossils (e.g., Mystacodon selenensis) indicates that the diversification of Crown Cetacea began before the Late Eocene and the divergence of Crown Delphinidae as early as the Middle Miocene. [Cetaceans; phylogenomics; Delphinidae; Ziphiidae; dolphins; whales.]
8
Maas, Mary C., and J. G. M. Thewissen. "Enamel microstructure of Pakicetus (Mammalia: Archaeoceti)." Journal of Paleontology 69, no. 6 (November 1995): 1154–63. http://dx.doi.org/10.1017/s0022336000038130.
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The tooth enamel of the earliest cetacean, Pakicetus, is described and compared to enamel of a primitive artiodactyl and a variety of primitive ungulate families. Pakicetus enamel organization, which is considered primitive for Cetacea, consists of a combination of radial and decussating enamel types. Prism patterns include prisms with open (horseshoe-shaped) and closed (circular) boundaries. Pakicetus enamel is similar to that of many primitive ungulates, including Diacodexis, the earliest artiodactyl, and Mesonychidae, an archaic ungulate family that often is considered close to the ancestry of Cetacea. This finding is consistent with the hypothesis, originally proposed on the basis of other aspects of morphology, that artiodactyls, cetaceans, and Mesonychidae are closely related.
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Kumarran, R. P. "Cetaceans and cetacean research in India." J. Cetacean Res. Manage. 12, no. 2 (February 8, 2023): 159–72. http://dx.doi.org/10.47536/jcrm.v12i2.573.
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The diversity of cetacean species in Indian waters is high, with 25 species recorded so far. Records of cetaceans from India during the last 200 years have provided insights into their spatiotemporal distribution, behaviour, feeding, reproduction, fishery interaction and pollution. The cetacean fauna is dominated by pantropical species, with a relatively high abundance of spinner dolphins, which is similar to other areas studied within the northern Indian Ocean. Historical records were analysed to propose an inventory of cetaceans. Cetacean diversity was highest in the Gulf of Mannar on the southeast coast of India, which with 14 species recorded from a small area can be considered a ‘hot spot’ for further research. Fishery interactions, domestic consumption, pollution and lack of quality information to inform management are the main threats for successful survival of cetaceans. The status of information regarding cetaceans in India could be classified based on this study as: six species with adequate data; five species where data is restricted to a few geographic locations; four species for which data collection is being initiated; five species with sparse data; and six species which are difficult to observe.
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Clegg, Isabella L. K. "What Does the Future Hold for the Public Display of Cetaceans?" Journal of Applied Animal Ethics Research 3, no. 2 (September 20, 2021): 240–78. http://dx.doi.org/10.1163/25889567-bja10023.
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Abstract In order to continue its business sustainably, any industry that uses animals must largely align their ethical position with that of the general public: ‘the mainstream social ethic’. Although zoos are transitioning from entertainment venues to conservation actors, many cetacean (whale and dolphin) facilities present the animals in unnatural-looking enclosures and entertainment-driven contexts. But what is the ‘mainstream social ethic’ regarding cetacean facilities, and what might it mean for the industry’s future? The evidence is first reviewed on cetacean welfare and the purported purposes for displaying cetaceans in the past and present. The mainstream social ethic is then defined, suggesting we may be at a crossroads for this industry. Welfare has improved in the last decades but could be further enhanced through providing more choice and control in cetaceans’ environments, particularly in enrichment, training and social groupings. Sanctuary settings provide a potential environment with more choice and control, but are still in the very initial stages of development. Fundamental, structural changes to the mission, presentation of the cetaceans and business model seem to be needed to realign the public display of cetaceans with the mainstream social ethic of the times.
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Marino, Lori. "Brain-Behavior Relations in Primates and Cetaceans: Implications for the Ubiquity of Factors Leading to the Evolution of Complex Intelligence." International Astronomical Union Colloquium 161 (January 1997): 553–60. http://dx.doi.org/10.1017/s0252921100015098.
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AbstractThis paper describes the results of a project aimed at addressing questions about the evolution of intelligence by utilizing comparisons of brain-behavior relations in cetaceans (dolphins and whales) and primates. Three specific questions were asked. First, have any cetaceans reached a hominid level of encephalization? Second, are cetacean-primate comparisons of brain organization useful for grappling with the differences that are bound to exist between any extraterrestrial organism and ourselves? Third, are there similarities in brain-behavior relations in cetaceans and primates that suggest behavioral evolution is shaped by general factors? Brain and body weights for cetacean and primate species were collected and compared with each other and with data on brain organization and social behavior. The results revealed that a hominid level of encephalization is not unique in mammalian history. Furthermore, cetacean-primate comparisons can be useful in understanding the different ways in which information processing systems can be organized. Finally, a comparison of the relation between encephalization and social group size in primates and cetaceans preliminarily suggests that similar mental capacities can be achieved through different independent evolutionary paths and that there may be factors common to behavioral evolution in all intelligent organisms.
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Lambert, C., M. Authier, G. Dorémus, A. Gilles, P. Hammond, S. Laran, A. Ricart, et al. "The effect of a multi-target protocol on cetacean detection and abundance estimation in aerial surveys." Royal Society Open Science 6, no. 9 (September 4, 2019): 190296. http://dx.doi.org/10.1098/rsos.190296.
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A double-platform protocol was implemented in the Bay of Biscay and English Channel during the SCANS-III survey (2016). Two observation platforms using different protocols were operating on board a single aircraft: the reference platform (Scans), targeting cetaceans, and the ‘Megafauna’ platform, recording all the marine fauna visible at the sea surface (jellyfish to seabirds). We tested for a potential bias in small cetacean detection and density estimation when recording all marine fauna. At a small temporal scale (30 s, roughly 1.5 km), our results provided overall similar perception probabilities for both platforms. Small cetacean perception was higher following the detection of another cetacean within the previous 30 s in both platforms. The only prior target that decreased small cetacean perception during the subsequent 30 s was seabirds, in the Megafauna platform. However, at a larger scale (study area), this small-scale perception bias had no effect on the density estimates, which were similar for the two protocols. As a result, there was no evidence of lower performance regarding small cetacean population monitoring for the multi-target protocol in our study area. Because our study area was characterized by moderate cetacean densities and small spatial overlap of cetaceans and seabirds, any extrapolation to other areas or time requires caution. Nonetheless, by permitting the collection of cost-effective quantitative data for marine fauna, anthropogenic activities and marine litter at the sea surface, the multi-target protocol is valuable for optimizing logistical and financial resources to efficiently monitor biodiversity and study community ecology.
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Tollis, Marc, Jooke Robbins, Andrew E. Webb, Lukas F. K. Kuderna, Aleah F. Caulin, Jacinda D. Garcia, Martine Bèrubè, et al. "Return to the Sea, Get Huge, Beat Cancer: An Analysis of Cetacean Genomes Including an Assembly for the Humpback Whale (Megaptera novaeangliae)." Molecular Biology and Evolution 36, no. 8 (May 9, 2019): 1746–63. http://dx.doi.org/10.1093/molbev/msz099.
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Abstract Cetaceans are a clade of highly specialized aquatic mammals that include the largest animals that have ever lived. The largest whales can have ∼1,000× more cells than a human, with long lifespans, leaving them theoretically susceptible to cancer. However, large-bodied and long-lived animals do not suffer higher risks of cancer mortality than humans—an observation known as Peto’s Paradox. To investigate the genomic bases of gigantism and other cetacean adaptations, we generated a de novo genome assembly for the humpback whale (Megaptera novaeangliae) and incorporated the genomes of ten cetacean species in a comparative analysis. We found further evidence that rorquals (family Balaenopteridae) radiated during the Miocene or earlier, and inferred that perturbations in abundance and/or the interocean connectivity of North Atlantic humpback whale populations likely occurred throughout the Pleistocene. Our comparative genomic results suggest that the evolution of cetacean gigantism was accompanied by strong selection on pathways that are directly linked to cancer. Large segmental duplications in whale genomes contained genes controlling the apoptotic pathway, and genes inferred to be under accelerated evolution and positive selection in cetaceans were enriched for biological processes such as cell cycle checkpoint, cell signaling, and proliferation. We also inferred positive selection on genes controlling the mammalian appendicular and cranial skeletal elements in the cetacean lineage, which are relevant to extensive anatomical changes during cetacean evolution. Genomic analyses shed light on the molecular mechanisms underlying cetacean traits, including gigantism, and will contribute to the development of future targets for human cancer therapies.
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Bauer, Gordon B., and Heidi E. Harley. "The mimetic dolphin." Behavioral and Brain Sciences 24, no. 2 (April 2001): 326–27. http://dx.doi.org/10.1017/s0140525x01243969.
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Rendell and Whitehead note the necessary, complementary relationship between field and laboratory studies in other species, but conclude their article by de-emphasizing the role of laboratory findings in cetacean research. The ambiguity in field studies of cetaceans should argue for greater reliance on the laboratory, which has provided much of the available research supporting the hypothesis of cetacean culture.
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Rossi-Santos, Marcos R., Elitieri Santos-Neto, and Clarêncio G. Baracho. "Interspecific cetacean interactions during the breeding season of humpback whale (Megaptera novaeangliae) on the north coast of Bahia State, Brazil." Journal of the Marine Biological Association of the United Kingdom 89, no. 5 (July 21, 2009): 961–66. http://dx.doi.org/10.1017/s0025315409000897.
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The large majority of cetacean interspecific studies report only on dolphin interactions, while studies on interactions between odontocete and mysticete are less common. The present work aims to report on sightings of cetacean interactions, during the breeding season of humpback whales(Megaptera novaeangliae), along 370 km of the Bahia State, north-eastern Brazil, addressing aspects of cetacean distribution and behaviour. During 7 seasons (2000–2006), a total of 230 research cruises were performed, in which 38 events of interactions among humpback whales and other cetaceans(Tursiops truncatus, Steno bredanensis, Peponocephala electraandBalaenoptera acutorostrata)were observed, plus another 5 encounters without the whale's presence, includingT. truncatus, S. bredanensis, P. electra, Stenella clymeneandStenella attenuata. Our results confirm the occurrence of multiple cetacean species in the Bahia State, being the first study in the world to report on a large range of interactions involving another 4 cetacean species, grouped with up to 3 mixed species per sighting, with humpback whales in their annual breeding ground.
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Clarke, Rohan H., Rosemary Gales, and Martin Schulz. "Land-based observations of cetaceans and a review of recent strandings at subantarctic Macquarie Island." Australian Mammalogy 39, no. 2 (2017): 248. http://dx.doi.org/10.1071/am16007.
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The occurrence of cetaceans around subantarctic Macquarie Island is poorly known. The current study provides the first quantitative assessment of the occurrence of various cetacean species in inshore waters during 391 systematic, one-hour observation periods over 59 weeks, in 2002 and 2003. Nine species of cetacean were identified during these surveys. Killer whales, long-finned pilot whales and sperm whales were all detected with some frequency. All other species were detected on single occasions. Eight previously unpublished stranding records are also summarised. These results support the notion that most cetacean species are relatively uncommon in the inshore waters of Macquarie Island. Routine archiving of cetacean sightings obtained during shipping activities in surrounding waters is encouraged as this will further contribute to our understanding of the region’s marine megafauna.
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Zheng, Jialu, Jianhua Wang, Zhen Gong, and Guan-Zhu Han. "Molecular fossils illuminate the evolution of retroviruses following a macroevolutionary transition from land to water." PLOS Pathogens 17, no. 7 (July 12, 2021): e1009730. http://dx.doi.org/10.1371/journal.ppat.1009730.
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The ancestor of cetaceans underwent a macroevolutionary transition from land to water early in the Eocene Period >50 million years ago. However, little is known about how diverse retroviruses evolved during this shift from terrestrial to aquatic environments. Did retroviruses transition into water accompanying their hosts? Did retroviruses infect cetaceans through cross-species transmission after cetaceans invaded the aquatic environments? Endogenous retroviruses (ERVs) provide important molecular fossils for tracing the evolution of retroviruses during this macroevolutionary transition. Here, we use a phylogenomic approach to study the origin and evolution of ERVs in cetaceans. We identify a total of 8,724 ERVs within the genomes of 25 cetaceans, and phylogenetic analyses suggest these ERVs cluster into 315 independent lineages, each of which represents one or more independent endogenization events. We find that cetacean ERVs originated through two possible routes. 298 ERV lineages may derive from retrovirus endogenization that occurred before or during the transition from land to water of cetaceans, and most of these cetacean ERVs were reaching evolutionary dead-ends. 17 ERV lineages are likely to arise from independent retrovirus endogenization events that occurred after the split of mysticetes and odontocetes, indicating that diverse retroviruses infected cetaceans through cross-species transmission from non-cetacean mammals after the transition to aquatic life of cetaceans. Both integration time and synteny analyses support the recent or ongoing activity of multiple retroviral lineages in cetaceans, some of which proliferated into hundreds of copies within the host genomes. Although ERVs only recorded a proportion of past retroviral infections, our findings illuminate the complex evolution of retroviruses during one of the most marked macroevolutionary transitions in vertebrate history.
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Miller, Cara, Aisake Batibasaga, Prerna Chand, Sirilo Dulunaqio, Margaret Fox, Stacy Jupiter, Waisea Naisilisili, Yashika Nand, Saras Sharma-Gounder, and Brian Smith. "Cetacean diversity, common occurrence and community importance in Fijian waters." Pacific Conservation Biology 22, no. 3 (2016): 272. http://dx.doi.org/10.1071/pc14933.
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Fiji has demonstrated a strong commitment to cetacean conservation via national, regional and international plans and agreements. To provide baseline information in support of these efforts, this paper provides an updated listing of cetacean species found in Fijian waters and identifies locations where cetaceans have been noted on a consistent basis. Information for this review was sourced from peer-reviewed publications, field reports, historical whaling records, national consultations, anecdotal and opportunistic sources, as well as a national database held by the Fiji Government’s Department of Fisheries. Reliable and recent records were confirmed for 10 cetacean species in Fijian waters. In addition, less reliable records and regional species’ information provides support for the occurrence of at least 14 additional species or groups of similar-looking species that could not be identified more specifically. Thirteen hotspot areas within the Fiji Economic Exclusive Zone were preliminarily identified as being particularly important for cetaceans, including numerous sites within the Vatu-i-Ra and Lomaiviti passages and surrounding waters. Issues with the available data include uneven coverage, inherent biases within available sources, and difficulties with species identification and verification in some cases. Nevertheless, it is hoped that this review will provide a reference point from which to move forward with cetacean management and conservation efforts in Fiji.
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Goetz, Sabine, Fiona L. Read, M. Begoña Santos, C. Pita, and Graham J. Pierce. "Cetacean–fishery interactions in Galicia (NW Spain): results and management implications of a face-to-face interview survey of local fishers." ICES Journal of Marine Science 71, no. 3 (September 16, 2013): 604–17. http://dx.doi.org/10.1093/icesjms/fst149.
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Abstract Galicia (NW Spain) is an important fishing region with a high potential for cetacean–fishery interactions. Cetacean depredation on catch and damage to fishing gear can potentially lead to substantial economic loss for fishers, while cetacean bycatch raises conservation concerns. With the aim of gathering information on the types and scale of interactions and of suggesting possible management strategies, we conducted face-to-face interviews with fishers in local fishing harbours, in particular to identify specific problematic interactions and to quantify the level of economic loss and bycatch rates associated with these interactions. We found that cetacean–fishery interactions are frequent, although damage to catch and fishing gear by cetaceans was mostly reported as small. Nevertheless, substantial economic loss can result from common bottlenose dolphins (Tursiops truncatus) damaging coastal gillnets and from short-beaked common dolphins (Delphinus delphis) scattering fish in purse-seine fisheries. Cetacean bycatch mortality was reported to be highest for trawls and set gillnets, and probably exceeds sustainable levels for local common and bottlenose dolphin populations. Although interview data may be biased due to the perceptions of interviewees, and therefore should be interpreted with care, the methodology allowed us to cover multiple sites and fisheries within a reasonable time frame. Minimizing cetacean–fishery interactions requires the implementation of case-specific management strategies with the active participation of fishers. For set gillnet and purse-seine fisheries, the use of acoustic deterrent devices (pingers) may prevent cetaceans from approaching and getting trapped in the nets. For trawl fisheries, where bycatch appears to be particularly high at night in water depths of 100–300 m, possible solutions include the implementation of time/area closures and the relocation of some fishing effort to deeper waters.
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Short, Michael Kirwan John. "Guanabara Bay Oil Spill 2000, Brazil – Cetacean Response." International Oil Spill Conference Proceedings 2003, no. 1 (April 1, 2003): 1035–37. http://dx.doi.org/10.7901/2169-3358-2003-1-1035.
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ABSTRACT On the 18th January 2000 a broken pipeline owned and operated by the oil company Petrobras spilt some 1300 tonne of bunker fuel into Guanabara Bay, Rio de Janeiro. The wildlife response was divided amongst 2 operational strategies and included – avian fauna and cetaceans. This paper deals with the cetacean response only. Cetaceans are generally not considered as an important feature of an oil spill response. Contingency planning for cetaceans in oil spills is now becoming an important element for preparedness for some countries. The cetacean response in Guanabara Bay specifically targeted a pod of about 70 members of the species Sotalia fluviatilis, a small dolphin that inhabits the bay. The response included the development of a plan that included a response system, a monitoring program and action plans. The response system detailed the mechanism for the plan to work and adopted the incident control management system. The monitoring program related to the study of any short term or long term deleterious effects resulting from the spill and consisted of basic spatial, temporal and behavioural studies. Action plans were developed specific to the character of Guanabara Bay and included the rescue and rehabilitation strategies necessary to respond to oil affected cetaceans. A training program was then developed and implemented to personnel who were to enact the cetacean response.
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Viddi, Francisco A., Rodrigo Hucke-Gaete, Juan P. Torres-Florez, and Sandra Ribeiro. "Spatial and seasonal variability in cetacean distribution in the fjords of northern Patagonia, Chile." ICES Journal of Marine Science 67, no. 5 (January 10, 2010): 959–70. http://dx.doi.org/10.1093/icesjms/fsp288.
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Abstract Viddi, F. A., Hucke-Gaete, R., Torres-Florez, J. P., and Ribeiro, S. 2010. Spatial and seasonal variability in cetacean distribution in the fjords of northern Patagonia, Chile. – ICES Journal of Marine Science, 67: 959–970. Compared with other Chilean coastal areas, little is known about the diversity and distribution of cetaceans in northern Patagonian fjords. Between December 2000 and November 2001, surveys on platforms of opportunity were undertaken in southern Chile to evaluate species richness and the spatial and seasonal distribution of cetaceans. Nine species were recorded, blue, humpback, and minke whales, Peale's dolphin, Chilean dolphin, killer whale, false killer whale, bottlenose dolphin, and Cuvier's beaked whale. The pattern of cetacean distribution displayed significant seasonal differences, with most baleen whales (mysticetes) observed during late summer and autumn, and toothed cetaceans (odontocetes) mostly during spring. Generalized additive models, used to assess the spatial distribution of cetaceans, showed that mysticetes were distributed disproportionately along a north–south gradient, in open gulfs with oceanic influence, and close to shore. In contrast, odontocetes were observed mainly within narrow channels, areas with complex coastal morphology, peaking at different water depths. These findings, although from a single year of data, increase our understanding of habitat determinants of cetacean distribution in southern Chile. The results have the potential to be applied to coastal conservation and management in the region.
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Raudina, Anggit Sapta, Sri Redjeki, and Nur Taufiq-Spj. "Biodiversitas dan Tingkah Laku Kemunculan Cetacea di Perairan Laut Sawu, Nusa Tenggara Timur." Journal of Marine Research 10, no. 4 (October 14, 2021): 453–62. http://dx.doi.org/10.14710/jmr.v10i4.30433.
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Perairan Indonesia memiliki lebih dari sepertiga jenis paus dan lumba-lumba dunia, termasuk juga beberapa jenis yang dikategorikan langka dan terancam punah. Beberapa jenis Cetacea yang menggunakan jalur migrasi melalui perairan Indonesia bagian Timur, antara lain Samudera Hindia dan Pasifik melalui perairan Kepulauan Komodo, Solor-Lembata (NTT), Laut Banda (Maluku), Sulawesi Tenggara, Sulawesi Utara dan Sorong-Fakfak (Papua). Hal ini menunjukkan bahwa Laut Sawu merupakan area pengasuhan dan mencari makan paus. Laut Sawu menjadi tempat potensial karena dijadikan jalur migrasi berbagai spesies Cetacea secara rutin. Sehingga penelitian ini bertujuan untuk menganalisa keanekaragaman dan tingkah laku Cetacea yang bermigrasi. Penelitian ini dilakukan pada bulan November 2018 di perairan sekitar Teluk Kupang dan Sulamu dengan menggunakan metode pengamatan single platform yang telah dimodifikasi. Data diolah melalui aplikasi ArcGIS 10.4 dan Microsoft Office Excel. Hasil penelitian menunjukkan bahwa jumlah kemunculan Cetacea berbeda-beda tiap spesiesnya dengan total 114 kali kemunculan. Aktivitas yang dilakukan Cetacea saat kemunculan sangat beragam, namun yang paling banyak yaitu aerials dan bowriding dari jenis lumba-lumba, kemudian logging dan spyhopping dari jenis paus. Dari data ini dapat disimpulkan bahwa, lumba-lumba mempunyai kebiasaan untuk cenderung bermigrasi dalam satu kelompok besar. Sehingga kemunculan lumba-lumba sangat mendominasi di perairan Laut Sawu dibanding kemunculan paus yang cenderung soliter maupun dalam kelompok lebih kecil. More than one third of the world's whales and dolphins are found in Indonesian waters, including several that are categorized as rare and endangered species. Several types of cetaceans - migrate use eastern part of Indonesian waters as a migration route, i.e. between the Indian and Pacific Oceans through the waters of the Komodo Islands, Solor-Lembata (NTT), Banda Sea (Maluku), Southeast Sulawesi, North Sulawesi and Sorong-Fakfak (Papua). This indicated that the Savu Sea is a region for whales feeding ground and for their breeding.Apart from being a potential place for the Savu Sea to be used as a regular migration route for various cetacean species, it also has very promising tourism potential. Other than that, Migratory cetacean species are also very diverse, so this research was aims to analyze the diversity and behavior of cetaceans that migrate every year. This research was done in November 2018 around the Bay of Kupang and Sulamu, and a modified single platform observation method was used. The data were processed through the ArcGIS 10.4 and Microsoft Office Excel. The result shows that the occurrence number of cetaceans was in different species with a total of 114 appearances. The activities carried out by cetaceans at the time of emergence were varied, but the most common were aerials and bow-riding by dolphins, then logging and spyhopping by whales. Dolphins themselves are animals that tend to group in one large group so that their appearance is very dominant compared to whales which tend to be solitary and aggregated in small groups.
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Andersen, R. Charles, Shahaama A. Sattar, and M. Shiham Adam. "Cetaceans in the Maldives: a review." J. Cetacean Res. Manage. 12, no. 2 (February 8, 2023): 219–25. http://dx.doi.org/10.47536/jcrm.v12i2.579.
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The cetaceans of the Maldives were poorly known until relatively recently, but have received increased attention over the past decade. Twentythree species of cetacean have now been recorded. A number of sightings surveys, and one acoustic survey, have been completed. The species most frequently seen is the spinner dolphin (Stenella longirostris). A national system for reporting cetacean strandings has been in place since 2000, although some earlier strandings were also reported; approximately 160 strandings of 16 species have been recorded to date. The species most commonly reported stranding is the sperm whale (Physeter macrocephalus). Ambergris has been exported from the Maldives since ancient times; recent export statistics are reviewed. All cetaceans are protected by law within Maldivian waters. More significantly, most forms of net-fishing, including gill-netting and purse-seining are banned in the Maldives to protect the traditional pole and line tuna fishery. Cetacean-watching is becoming increasingly popular, with spinner dolphins being the main attraction, although other species are also sought after on specialist trips.
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Afsal, V. V., K. S. S. M. Yousuf, B. Anoop, P. Kannan, M. Rajagopalan, and E. Vivekanandan. "A note on cetacean distribution in the Indian EEZ and contiguous seas during 2003-07." J. Cetacean Res. Manage. 10, no. 3 (February 15, 2023): 209–15. http://dx.doi.org/10.47536/jcrm.v10i3.637.
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Relatively little is known about the distribution of cetaceans in Indian seas due to lack of systematic surveys. For collecting data on species distribution, 35 opportunistic surveys were conducted onboard FORV Sagar Sampada between October 2003 and February 2007 in the Indian EEZ and contiguous seas. In 5,254 hours of sighting effort, a total of 473 cetacean records were made with 5,865 individuals. The occurrence of 10 species from three cetacean families was confirmed. The Indo-Pacific bottlenose dolphin was the most frequently sighted species, whereas the spinner dolphin was dominant in terms of abundance. Long-beaked common dolphins, Indo-Pacific hump-backed dolphin and sperm whales were also recorded at frequent intervals. Cetaceans were found to have a wide geographical distribution in the Indian EEZ and contiguous seas. High abundance and species richness were recorded in the Southeastern Arabian Sea and southern Sri Lankan waters. From the information collected during the present study, the platform of opportunity has proved to be a useful means for cetacean survey.
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Coram, Amber, Neil Angelo S. Abreo, Robert P. Ellis, and Kirsten F. Thompson. "Contribution of social media to cetacean research in Southeast Asia: illuminating populations vulnerable to litter." Biodiversity and Conservation 30, no. 8-9 (May 18, 2021): 2341–59. http://dx.doi.org/10.1007/s10531-021-02196-6.
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AbstractLitter in the marine environment, in particular plastic, is a significant threat to marine megafauna. Cetaceans are known to ingest or become entangled in marine debris, likely impacting individuals and populations. Southeast Asia is a biodiversity hotspot and harbours a diverse cetacean assemblage. However, there are key knowledge gaps relating to the impact of litter in this region due the lack of experts to survey its vast coastlines. This study aims to address such gaps by using social media, gathering data from Facebook posts relating to cetacean strandings and litter across Southeast Asia between 2009 and 2019. Results show that at least 15 cetacean species have been negatively affected by litter, with ingestion most commonly affecting deep-diving species. Epipelagic and mesopelagic foragers were most vulnerable to entanglement. Davao in the Philippines was identified as a litter-related stranding hotspot. The Irrawaddy dolphin (Orcaella brevirostris) and pygmy sperm whale (Kogia breviceps) are particularly vulnerable to litter. The combination of social media and peer reviewed literature can help build a more complete picture of the spatial distribution of marine litter and the scale of the impact it has on cetacean populations. In this study we provide details of a valuable online tool for helping to understand the impact of marine litter on cetaceans and other charismatic species that are a focus of community engagement.
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Thewissen, J. G. M., and F. E. Fish. "Locomotor evolution in the earliest cetaceans: functional model, modern analogues, and paleontological evidence." Paleobiology 23, no. 4 (1997): 482–90. http://dx.doi.org/10.1017/s0094837300019850.
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We discuss a model for the origin of cetacean swimming that is based on hydrodynamic and kinematic data of modern mammalian swimmers. The model suggests that modern otters (Mustelidae: Lutrinae) display several of the locomotor modes that early cetaceans used at different stages in the transition from land to water. We use mustelids and other amphibious mammals to analyze the morphology of the Eocene cetacean Ambulocetus natans, and we conclude that Ambulocetus may have locomoted by a combination of pelvic paddling and dorsoventral undulations of the tail, and that its locomotor mode in water resembled that of the modern otter Lutra most closely. We also suggest that cetacean locomotion may have resembled that of the freshwater otter Pteronura at a stage beyond Ambulocetus.
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Dungan, Sarah Z., and Belinda S. W. Chang. "Epistatic interactions influence terrestrial–marine functional shifts in cetacean rhodopsin." Proceedings of the Royal Society B: Biological Sciences 284, no. 1850 (March 2017): 20162743. http://dx.doi.org/10.1098/rspb.2016.2743.
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Like many aquatic vertebrates, whales have blue-shifting spectral tuning substitutions in the dim-light visual pigment, rhodopsin, that are thought to increase photosensitivity in underwater environments. We have discovered that known spectral tuning substitutions also have surprising epistatic effects on another function of rhodopsin, the kinetic rates associated with light-activated intermediates. By using absorbance spectroscopy and fluorescence-based retinal release assays on heterologously expressed rhodopsin, we assessed both spectral and kinetic differences between cetaceans (killer whale) and terrestrial outgroups (hippo, bovine). Mutation experiments revealed that killer whale rhodopsin is unusually resilient to pleiotropic effects on retinal release from key blue-shifting substitutions (D83N and A292S), largely due to a surprisingly specific epistatic interaction between D83N and the background residue, S299. Ancestral sequence reconstruction indicated that S299 is an ancestral residue that predates the evolution of blue-shifting substitutions at the origins of Cetacea. Based on these results, we hypothesize that intramolecular epistasis helped to conserve rhodopsin's kinetic properties while enabling blue-shifting spectral tuning substitutions as cetaceans adapted to aquatic environments. Trade-offs between different aspects of molecular function are rarely considered in protein evolution, but in cetacean and other vertebrate rhodopsins, may underlie multiple evolutionary scenarios for the selection of specific amino acid substitutions.
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Mence, David. "The cetacean right to life revisited." International Journal of Law in Context 11, no. 1 (March 2015): 17–39. http://dx.doi.org/10.1017/s1744552314000342.
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AbstractMany cetaceans are borderline persons and, as such, have a right to life. This is partly a normative and partly a positive legal claim. While many philosophers agree that cetaceans possess limited moral rights, it can also be shown that most states already behave as though they possess limited legal rights. The most basic of these, the right to life, reflects shifting contemporary norms – especially given scientific evidence as to cetacean sentience, intelligence and autonomy – and the consolidation of customary international law. The recent decision of the International Court of Justice in Whaling in the Antarctic (2014) includes importantobiter dictato this effect and arguably suggests an avenue for future doctrinal development in this area. Nevertheless, while the cetacean right to life already exists, there are a number of obstacles that preclude its enforcement. Perhaps the most significant of these remain the traditional status of the world's oceans as a global commons and the weak sovereignty of international law.
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Loiselle, Hope. "Humans, Dolphins, and Porpoises: Investigations at the Par-Tee Site, Seaside, Oregon, AD 100–800." Ethnobiology Letters 11, no. 1 (August 14, 2020): 58–66. http://dx.doi.org/10.14237/ebl.11.1.2020.1662.
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Small cetaceans are understudied compared to whales and pinnipeds even though they represent a high-ranking prey choice when available in the environment. Building upon previous faunal analyses at the Par-Tee site, Seaside, Oregon that investigated whaling, this analysis of dolphin and porpoise remains suggests that people were hunting small cetaceans between AD 100–800 on the Oregon coast, especially harbor porpoise, which was found significantly more than any other cetacean species at the site. The quantity of small cetacean bone is unlikely to be the result of only acquiring stranded individuals. While there is no direct evidence of hunting, ethnographic literature and archaeologically recovered hunting technologies like harpoons provide insight into the means by which these species may have been hunted.
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Groves, Sabrina L., Carlos Mauricio Peredo, and Nicholas D. Pyenson. "What are the limits on whale ear bone size? Non-isometric scaling of the cetacean bulla." PeerJ 9 (February 5, 2021): e10882. http://dx.doi.org/10.7717/peerj.10882.
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The history of cetaceans demonstrates dramatic macroevolutionary changes that have aided their transformation from terrestrial to obligate aquatic mammals. Their fossil record shows extensive anatomical modifications that facilitate life in a marine environment. To better understand the constraints on this transition, we examined the physical dimensions of the bony auditory complex, in relation to body size, for both living and extinct cetaceans. We compared the dimensions of the tympanic bulla, a conch-shaped ear bone unique to cetaceans, with bizygomatic width—a proxy for cetacean body size. Our results demonstrate that cetacean ears scale non-isometrically with body size, with about 70% of variation explained by increases in bizygomatic width. Our results, which encompass the breadth of the whale fossil record, size diversity, and taxonomic distribution, suggest that functional auditory capacity is constrained by congruent factors related to cranial morphology, as opposed to allometrically scaling with body size.
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Scott, N. J., and E. C. M. Parsons. "A survey of public awareness of the occurrence and diversity of cetaceans in south-west Scotland." Journal of the Marine Biological Association of the United Kingdom 84, no. 5 (October 2004): 1101–4. http://dx.doi.org/10.1017/s0025315404010537h.
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In summer 2001, members of the public in south-west Scotland were interviewed to determine their knowledge of the diversity and occurrence of cetaceans in the region. Interviews were conducted in both rural island and coastal communities and a major city.The majority of interviewees (46%) underestimated the number of cetacean species occurring in western Scottish waters (i.e. <10 species). Only 4·4% gave the correct answer (24). Location of the participant affected the level of knowledge. Photographs were presented of the four most commonly occurring cetacean species: only 30·2% correctly identified one or more of the species. The species most frequently identified correctly was the bottlenose dolphin (19% of interviewees) followed by the harbour porpoise (17·5%), minke whale (10·7%) and, lastly, the common dolphin (7·1%).Interviewees were also asked whether certain cetacean species occurred in local waters or not. The level of awareness was generally low. The most common positive answers involved the bottlenose dolphin, harbour porpoise, and minke whale. Only one in five were aware of killer whales and 13·1% believed that grey whales occurred in Scottish waters. Knowledge of species occurrence showed statistically significant relationships with age, gender, level of environmental interest and location, but not occupation (teachers, tourism professionals and marine stakeholders did not show greater levels of cetacean knowledge). The study identified target groups and locations where knowledge of cetaceans is low and environmental education efforts should be concentrated.
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Weir, Caroline R. "Occurrence and distribution of cetaceans off northern Angola, 2004/05." J. Cetacean Res. Manage. 9, no. 3 (February 22, 2023): 225–39. http://dx.doi.org/10.47536/jcrm.v9i3.671.
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The occurrence and distribution of cetacean species off northern Angola was examined using dedicated survey data and incidental sighting records. Dedicated surveys for cetaceans were carried out during two geophysical seismic surveys off northern Angola between August 2004 and September 2005. A total of 3,268hr of survey effort data were collected, resulting in 779 on-effort cetacean sightings. There were 263 sightings reported off-effort and incidentally from other platforms and sports fishermen. With 21 cetacean species confirmed, the cetacean community off northern Angola is diverse and primarily tropical in characteristic, comprising four species of baleen whale, two sperm whale species, at least two beaked whale species, and 13 species of delphinid. Humpback and sperm whales were the most frequently recorded cetaceans. The occurrence of humpback whales was significantly higher within neritic waters, and during the winter and spring months in association with seasonal occupancy of their West African breeding grounds. Sperm whales were recorded in water depths exceeding 1,000m and demonstrated significant seasonality, with peak occurrence during the summer and autumn. Atlantic spotted dolphins and common dolphins (Delphinus sp.) were the most numerous delphinids recorded, with spotted dolphins showing a significant seasonal peak during the spring and summer, and common dolphins in the winter. Other species recorded included fin whale, sei whale, Bryde’s whale, dwarf sperm whale, Cuvier’s and Mesoplodon beaked whales, killer whale, short-finned pilot whale, false killer whale, melon-headed whale, Atlantic humpback dolphin, rough-toothed dolphin, Risso’s dolphin, bottlenose dolphin, Pantropical spotted dolphin, spinner dolphin, Clymene dolphin and striped dolphin. Further research is required to document the cetacean community in Angola, particularly given the unknown threat from fishery bycatch and the increasing level of oil and gas exploration in the region.
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Xu, Shixia, Yuan Chen, Yuefeng Cheng, Dan Yang, Xuming Zhou, Junxiao Xu, Kaiya Zhou, and Guang Yang. "Positive selection at the ASPM gene coincides with brain size enlargements in cetaceans." Proceedings of the Royal Society B: Biological Sciences 279, no. 1746 (September 12, 2012): 4433–40. http://dx.doi.org/10.1098/rspb.2012.1729.
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The enlargement of cetacean brain size represents an enigmatic event in mammalian evolution, yet its genetic basis remains poorly explored. One candidate gene associated with brain size evolution is the abnormal spindle-like microcephaly associated (ASPM), as mutations in this gene cause severe reductions in the cortical size of humans. Here, we investigated the ASPM gene in representative cetacean lineages and previously published sequences from other mammals to test whether the expansion of the cetacean brain matched adaptive ASPM evolution patterns. Our analyses yielded significant evidence of positive selection on the ASPM gene during cetacean evolution, especially for the Odontoceti and Delphinoidea lineages. These molecular patterns were associated with two major events of relative brain size enlargement in odontocetes and delphinoids. It is of particular interest to find that positive selection was restricted to cetaceans and primates, two distant lineages both characterized by a massive expansion of brain size. This result is suggestive of convergent molecular evolution, although no site-specific convergence at the amino acid level was found.
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Nanayakkara, Ranil P., Jayampathi Herath, and Ruvinda K. de Mel. "Cetacean Presence in the Trincomalee Bay and Adjacent Waters, Sri Lanka." Journal of Marine Biology 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/819263.
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In Sri Lanka thirty species of cetaceans have been recorded to date. The canyon at Trincomalee bay is a multiple submarine canyon complex and anecdotal reports suggest that the Trincomalee bay and its adjacent waters are utilised by a number of cetacean species. Though Cetaceans are known to be abundant in the waters off Trincomalee there is a dearth of research and data pertaining to the abundance and species frequenting the Trincomalee bay and its adjacent waters. As such the current study was initiated, to get a consensus of the abundance and occurrences of species in Trincomalee Bay and its adjacent waters. Field surveys were carried out for 19 months and the research platform was a 35-foot commercial fishing vessel. 177 cetacean encounters were recorded on 67 of the 75 field days. Remarkably a total of 11 species of cetaceans which composed of two species of Baleen Whales and nine species of Toothed Whales were recorded. Delphinidae was the most common family recorded, followed by Balaenopteridae, Ziphiidae, Physeteridae, and Kogiidae. Spinner Dolphins were the most abundant cetacean owing to the large pods observed and the regularity of the sightings. They were the only species seen feeding/traveling with birds and fish (tuna). Sperm Whales, Blue Whales, and Bryde’s Whales were also relatively common. Two records of interspecific association between cetaceans were recorded. The increase in the human population in the study area has resulted in the overexploitation of marine resources which has dire repercussions on the marine mammal communities found in these waters.
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Echeverri-Zuluaga, Manuela, Yeison H. Duque-García, and Julian Ruiz-Saenz. "Morbillivirus de los Delfines: Patógeno re-emergente en la población de cetáceos." Universitas Scientiarum 20, no. 1 (August 11, 2014): 29. http://dx.doi.org/10.11144/javeriana.sc20-1.mdpr.
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Dolphin morbillivirus (DMV) is one of the most important pathogen of cetaceans. It was first described in the late 80s, since has been causing outbreaks that affects dolphin populations and also in other cetaceans in the U.S. and in the Mediterranean sea. We conducted a bibliographic search in MedLine, SciELO, Scopus® and Google Scholar without timeline limits using MeSH terms such as Cetacean morbillivirus, Pilot Whale morbillivirus, Dolphin morbillivirus, Strandings, etc., with the aim of provide a critical update on basic, clinical and epidemiological aspects of one of the most important emerging infections for cetacean wildlife, with particular emphasis on the current alternatives for diagnosis and control. Based on the information gathered we concluded that there is not only a need to study and quantify the strandings, but we need to develop awareness of the importance of this viral infection in cetaceans and to apply effective management plans that maintain those populations in biological balance.
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Andrews, Russel D., Robin W. Baird, John Calambokidis, Caroline E. C. Goertz, Frances M. D. Gulland, Mads Peter Heide-Jorgensen, Sascha K. Hooker, et al. "Best practice guidelines for cetacean tagging." IWC Journal of Cetacean Research and Management 20, no. 1 (January 1, 2019): 27–66. http://dx.doi.org/10.47536/jcrm.v20i1.237.
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Animal-borne electronic instruments (tags) are valuable tools for collecting information on cetacean physiology, behaviour and ecology, and forenhancing conservation and management policies for cetacean populations. Tags allow researchers to track the movement patterns, habitat use andother aspects of the behaviour of animals that are otherwise difficult to observe. They can even be used to monitor the physiology of a taggedanimal within its changing environment. Such tags are ideal for identifying and predicting responses to anthropogenic threats, thus facilitating thedevelopment of robust mitigation measures. With the increasing need for data best provided by tagging and the increasing availability of tags, suchresearch is becoming more common. Tagging can, however, pose risks to the health and welfare of cetaceans and to personnel involved in taggingoperations. Here we provide ‘best practice’ recommendations for cetacean tag design, deployment and follow-up assessment of tagged individuals,compiled by biologists and veterinarians with significant experience in cetacean tagging. This paper is intended to serve as a resource to assist tagusers, veterinarians, ethics committees and regulatory agency staff in the implementation of high standards of practice, and to promote the trainingof specialists in this area. Standardised terminology for describing tag design and illustrations of tag types and attachment sites are provided, alongwith protocols for tag testing and deployment (both remote and through capture-release), including training of operators. The recommendationsemphasise the importance of ensuring that tagging is ethically and scientifically justified for a particular project and that tagging only be used toaddress bona fide research or conservation questions that are best addressed with tagging, as supported by an exploration of alternative methods.Recommendations are provided for minimising effects on individual animals (e.g. through careful selection of the individual, tag design and implantsterilisation) and for improving knowledge of tagging effects on cetaceans through increased post-tagging monitoring.
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Williams, Rob, Anna Hall, and Arliss Winship. "Potential limits to anthropogenic mortality of small cetaceans in coastal waters of British Columbia." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 9 (September 2008): 1867–78. http://dx.doi.org/10.1139/f08-098.
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Small cetaceans are by-caught in salmon gillnet fisheries in British Columbia (BC) waters. In Canada, there is currently no generic calculation to identify when management action is necessary to reduce cetacean bycatch below sustainable limits. We estimated potential anthropogenic mortality limits for harbour ( Phocoena phocoena ) and Dall’s ( Phocoenoides dalli ) porpoises and Pacific white-sided dolphins ( Lagenorhynchus obliquidens ) using quantitative objectives from two well-established frameworks for conservation and management (the United States’ Marine Mammal Protection Act and the Agreement on the Conservation of Small Cetaceans of the Baltic and North Seas), which are similar to some management objectives developed for marine mammal stocks elsewhere in Canada. Limits were calculated as functions of (i) a minimum abundance estimate (2004–2005); (ii) maximum rate of population increase; and (iii) uncertainty factors to account for bias in abundance estimates and uncertainty in mortality estimates. Best estimates of bycatch mortality in 2004 and 2005 exceeded only the most precautionary limits and only for porpoise species. Future research priority should be given to determining small cetacean stock structure in BC and refining species-specific entanglement rates in these and other fisheries. The approach offers a quantitative framework for Canada to meet its stated objectives to maintain favourable conservation status of cetacean populations.
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de Boer, Marijke N. "Cetacean distribution and relative abundance in offshore Gabonese waters." Journal of the Marine Biological Association of the United Kingdom 90, no. 8 (July 28, 2010): 1613–21. http://dx.doi.org/10.1017/s0025315410001165.
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Information on cetaceans off Gabon in tropical West Africa is summarized from boat-based surveys carried out between 7 March and 7 August 2009. Thirteen cetacean species were positively identified comprising two baleen whale species, one sperm whale species and ten species of delphinid. Bryde's whale (Balaenoptera brydei) and humpback whale (Megaptera novaeangliae) were the most frequently encountered species. Cetaceans were found throughout a range of sea surface temperature between 20.5°C and 27.5°C and a wide range of depths with the majority of effort and sightings occurring seaward of the shelf break. Of particular interest from the study were the following: (1) Gabonese waters have a broad cetacean diversity, especially with a large and diversified delphinid community in the northern part of the study area; (2) the variations in oceanographic conditions within Gabonese waters are likely to result in a temporal variation in species composition; (3) the sightings of Atlantic spotted dolphin (Stenella frontalis) are the first at-sea sightings confirmed for these waters, although not unexpected given their distribution and abundant presence in surrounding waters; and (4) the poorly known Clymene dolphin (Stenella clymene) was sighted on four occasions in deep oceanic waters and was the most abundant cetacean. These are the first confirmed records of Clymene dolphins in Gabonese waters.
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Rendell, Luke, Mauricio Cantor, Shane Gero, Hal Whitehead, and Janet Mann. "Causes and consequences of female centrality in cetacean societies." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1780 (July 15, 2019): 20180066. http://dx.doi.org/10.1098/rstb.2018.0066.
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Cetaceans are fully aquatic predatory mammals that have successfully colonized virtually all marine habitats. Their adaptation to these habitats, so radically different from those of their terrestrial ancestors, can give us comparative insights into the evolution of female roles and kinship in mammalian societies. We provide a review of the diversity of such roles across the Cetacea, which are unified by some key and apparently invariable life-history features. Mothers are uniparous, while paternal care is completely absent as far as we currently know. Maternal input is extensive, lasting months to many years. Hence, female reproductive rates are low, every cetacean calf is a significant investment, and offspring care is central to female fitness. Here strategies diverge, especially between toothed and baleen whales, in terms of mother–calf association and related social structures, which range from ephemeral grouping patterns to stable, multi-level, societies in which social groups are strongly organized around female kinship. Some species exhibit social and/or spatial philopatry in both sexes, a rare phenomenon in vertebrates. Communal care can be vital, especially among deep-diving species, and can be supported by female kinship. Female-based sociality, in its diverse forms, is therefore a prevailing feature of cetacean societies. Beyond the key role in offspring survival, it provides the substrate for significant vertical and horizontal cultural transmission, as well as the only definitive non-human examples of menopause. This article is part of the theme issue ‘The evolution of female-biased kinship in humans and other mammals’.
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Rodriguez-Ferrer, Grisel, Roberto Reyes, Nicholas M. Hammerman, and Jaaziel E. García-Hernández. "Cetacean sightings in Puerto Rican waters: including the first underwater photographic documentation of a minke whale (Balaenoptera acutorostrata)." Latin American Journal of Aquatic Mammals 13, no. 1-2 (February 21, 2019): 26–36. http://dx.doi.org/10.5597/00246.
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Opportunistic encounters by experts and the public (i.e. fishermen, tourists) can be great assets to understanding cetacean distribution, especially in areas where surveys are limited. Sightings of Puerto Rican pelagic cetaceans have been reported in the past, with known seasonality in some species. Within this report, we document sightings for eight species, report new monthly distributions for three of these species, as well as the presence of rough-toothed dolphins close to the coast, and the first underwater sighting of a minke whale (Balaenoptera acutorostrata) off San Juan, Puerto Rico. Unfortunately, the lack of long-term studies due to limited funding and resources has been an obstacle in determining species diversity and overall health of cetacean populations. However, this note provides evidence that collaboration between marine biologists and citizen-based science is possible and desired, and serves as a valuable resource to protect and conserve native, pelagic, and transient cetacean species around Puerto Rican waters.
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Pyenson, Nicholas D. "Carcasses on the coastline: measuring the ecological fidelity of the cetacean stranding record in the eastern North Pacific Ocean." Paleobiology 36, no. 3 (2010): 453–80. http://dx.doi.org/10.1666/09018.1.
Full textAbstract:
To understand how well fossil assemblages represent original communities, paleoecologists seek comparisons between death assemblages and their source communities. These comparisons have traditionally used nearshore, marine invertebrate assemblages for their logistical ease, high abundance, and comparable census data from living communities. For large marine vertebrates, like cetaceans, measuring their diversity in ocean ecosystems is difficult and expensive. Cetaceans, however, often beach or strand themselves along the coast, and archived data on stranded cetaceans have been recorded, in some areas, over several decades. If the stranding record is interpreted as a death assemblage, then the stranding record may represent a viable alternative for measuring diversity in living communities on directly adjacent coastlines. This study assessed the fidelity of the cetacean stranding record in the eastern North Pacific Ocean. The living community in this region has been studied for over 100 years and, recently, extensive and systematic live transect surveys using ship-based observing platforms have produced a valuable source of live diversity data. Over this same period, the U.S. Marine Mammal Stranding Program has collected and archived a record of cetacean strandings along the U.S. Pacific coastline, providing an ideal death assemblage for comparison. Using fidelity metrics commonly used in marine invertebrate taphonomy, I determined that the stranding record samples the living cetacean community with high fidelity, across fine and coarse taxonomic ranks, and at large geographic scales (>1000 km of coastline). The stranding record is also richer than the live surveys, with live-dead ratios between 1.1 and 1.3. The stranding record recovers similar rank-order relative abundances as live surveys, with statistical significance. Also, I applied sample-based rarefaction methods to generate collector's curves for strandings along the U.S. Pacific Coast to better evaluate the spatiotemporal characteristics of the stranding record. Results indicate that saturation (i.e., sampling >95% assemblage) at species, genus, and family levels occurs in less than five years of sampling, with families accumulating faster than species, and larger geographic regions (i.e., longer coastlines) accumulating taxa the most rapidly. The high fidelity of the stranding record, measured both in richness and by ranked relative abundance, implies that ecological structure from living cetacean communities is recorded in the death assemblage, a finding that parallels marine invertebrate assemblages, though at far larger spatial scales. These results have implications for studying cetacean ecology in both modern and ancient environments: first, these results imply that the stranding record, over sufficiently long time intervals, yields a richer assemblage than using line-transect methods, and faithfully records aspects of community structure; and second, these results imply that geochronologically well-constrained fossil cetacean assemblages might preserve ecologically relevant features of community structure, depending on depositional and taphonomic conditions.
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Boys, Rebecca M., Ngaio J. Beausoleil, Emma L. Betty, and Karen A. Stockin. "Deathly Silent: Exploring the Global Lack of Data Relating to Stranded Cetacean Euthanasia." Animals 11, no. 5 (May 19, 2021): 1460. http://dx.doi.org/10.3390/ani11051460.
Full textAbstract:
The compromised state of stranded cetaceans means that euthanasia is often required. However, current knowledge and implementation of euthanasia methods remain highly variable, with limited data on the practicalities and welfare impacts of procedures. This study evaluated the available published data on cetacean euthanasia, highlighting knowledge gaps and providing direction to improve stranded cetacean welfare. A total of 2147 peer-reviewed articles describing marine mammal euthanasia were examined. Of these 3.1% provided details on the method used, with 91% employing chemical methods. Two countries, the United Kingdom (UK) and New Zealand (NZ), provided euthanasia reports to the International Whaling Commission (IWC) between 2007 and 2020. Methods employed were reported for 78.3% and 100% of individual cetaceans euthanised in the UK and NZ, respectively. In the UK, chemical euthanasia was most common (52%), whilst in NZ only ballistics methods were used. Few data were available about time to death/insensibility (TTD); 0.5% of peer-reviewed articles provided TTD, whilst TTD was reported for 35% of individuals in the UK and for 98% in NZ. However, IWC reports lacked detail on how death/insensibility were assessed, with multiple individuals “presumed instantly” killed. Overall, the findings highlight the lack of available information on cetacean euthanasia, and suggest increased data collection and the application of appropriate methods to improve welfare.
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Simmonds, Mark P., and Wendy J. Eliott. "Climate change and cetaceans: concerns and recent developments." Journal of the Marine Biological Association of the United Kingdom 89, no. 1 (February 2009): 203–10. http://dx.doi.org/10.1017/s0025315408003196.
Full textAbstract:
At least a quarter of the world's cetaceans were recently confirmed as endangered and the situation may be worse as the status of many others remains unclear. Climate change is affecting the oceans and a number of studies have recently highlighted its potential impact on cetacean species - for example, there are important linkages between sea ice and krill, the primary prey for baleen whales in Antarctica. This paper provides a synthesis of new information available on this theme and considers its implications for the future conservation and management of cetacean populations and species.The more mobile (or otherwise adaptable) cetaceans may be able to respond to climate related changes, although the extent of this adaptability is largely unknown. However, there is broad agreement that certain species and populations are likely to be especially vulnerable to climate related changes, including those with a limited habitat range, or those for which sea ice provides an important habitat for the cetacean population and/or that of their prey. International conservation bodies, such as the Convention for Migratory Species and the International Whaling Commission, are striving to address these issues. The challenges presented by climate change require an innovative, large scale, long term and multinational response from scientists, conservation managers and decision makers. This response that should encompass a precautionary approach, including addressing the detrimental effects of other factors negatively impacting populations and species.
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Auge, Amelie A., Hellen Otley, Nick Rendell, and Veronica F. Frans. "Spatial distribution of cetacean strandings in the Falkland Islands to define monitoring opportunities." J. Cetacean Res. Manage. 19, no. 1 (January 24, 2023): 1–7. http://dx.doi.org/10.47536/jcrm.v19i1.410.
Full textAbstract:
The waters around the Falkland Islands are used by many species of cetaceans, including endangered and data deficient species, but little is knownabout their populations. The Falkland Islands cetacean stranding database was transformed in a geo-spatial database using the available descriptionsof the locations as no GPS locations were recorded until 2015. It was then used to analyse the spatial distribution of strandings over a periodspanning the 1880s to 2015. A total of 169 stranding events could be given a location and mapped. Twelve stranding hotspots were identified. Thispaper also reports on the first recorded stranding of false killer-whales (Pseudorca crassidens) and Antarctic minke whale (Balaenoptera bonaerensis)in the Falkland Islands, increasing the total species recorded to 26. Spatially-explicit cetacean stranding databases can provide important data tomonitor cetaceans in the light of environmental changes from climate change or industrial development. In the case of the Falkland Islands (remoteand sparsely inhabited), identification of hotspots could be used to design an aerial monitoring programme to increase chances of detecting strandingevents, organise a rescue or necropsy team to gain samples. The results in this paper should enhance local capacity to conduct research (samplecollection for pollutant analyses, genetic studies, etc.) and monitor impacts of human activities on cetacean populations, including from the historicalbaseline of average numbers and distribution of strandings provided.
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Compton, Ross, Aaron Banks, Lissa Goodwin, and Sascha K. Hooker. "Pilot cetacean survey of the sub-Arctic North Atlantic utilizing a cruise-ship platform." Journal of the Marine Biological Association of the United Kingdom 87, no. 1 (February 2007): 321–25. http://dx.doi.org/10.1017/s0025315407054781.
Full textAbstract:
Using a large passenger cruise-ship (MV ‘Discovery’) as a platform, a cetacean survey was conducted between 1 August and 3 September 2005 across the northern North Atlantic Ocean and back, covering waters between the UK, Iceland, Greenland and Canada. The objective was to collect sightings data for all cetacean species encountered to begin to collate information for a large-scale sightings database. Two observers employed standard-distance sampling techniques and visual observations (naked eye) to scan for cetaceans during daylight hours and favourable weather conditions. Approximately 112 h were spent surveying over 23 d. A total of 13 cetacean species were encountered, with 173 separate sightings recorded, totalling over 2000 animals. The most commonly sighted species were minke whales (Balaenoptera acutorostrata: N=44), Atlantic white-sided dolphins (Lagenorhynchus acutus: N=34, with group sizes of up to 600), and humpback whales (Megaptera novaeangliae: N=31). The distribution of minke whales, Atlantic white-sided dolphins and fin whales was linked to underlying oceanographic variables. Overall patterns of distribution were consistent with our understanding of the summer distributions for the species encountered. The survey highlighted the cetacean diversity of the northern North Atlantic region. Repeat work using this methodology will allow an examination of species' distributions and estimation of their relative abundance.
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Clark, Rebecca A., Christopher M. Johnson, Genevieve Johnson, Roger Payne, Iain Kerr, R. Charles Andersen, Shahaama A. Sattar, Celine A. J. Godard, and Peter T. Madsen. "Cetacean sightings and acoustic detections in the offshore waters of the Maldives during the northeast monsoon seasons of 2003 and 2004." J. Cetacean Res. Manage. 12, no. 2 (February 8, 2023): 227–34. http://dx.doi.org/10.47536/jcrm.v12i2.580.
Full textAbstract:
Despite its central position in the Indian Ocean Sanctuary, little is known about the offshore cetacean fauna of the Maldives. Here we report survey results gathered by the R/V Odyssey in the Maldives during the 2003 and 2004 northeast monsoon seasons, and provide data on cetaceans from visual and acoustic observations. The survey was conducted over a period of 72 days and covered 10,915 track line kilometres. The main aim of the survey was to collect biopsy samples from sperm whales (Physeter macrocephalus) as part of a global survey of ocean pollutants. Totals of 157 sightings and 1,461 acoustic detections of 16 identified cetacean species were recorded. Risso’s dolphin (Grampus griseus), pantropical spotted dolphin (Stenella attenuata), spinner dolphin (Stenella longirostris) and sperm whale were the most commonly sighted species. Sperm whales and pantropical spotted dolphins were particularly abundant in the southern Maldives. The cetacean acoustic detection rate was 2.5 times higher than in the eastern Indian Ocean and Western tropical Pacific, while the non-physeterid sighting rate was 1.7 times higher than the Eastern tropical Pacific and 6.7 times higher than the eastern Indian Ocean based on other research conducted by the R/V Odyssey using the same methodology. It is concluded that the Maldives has a diverse and seemingly abundant cetacean community.
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Gol'din, Pavel, and Evgenij Zvonok. "Basilotritus uheni, a new cetacean (Cetacea, Basilosauridae) from the late middle Eocene of eastern Europe." Journal of Paleontology 87, no. 2 (March 2013): 254–68. http://dx.doi.org/10.1666/12-080r.1.
Full textAbstract:
A new basal basilosaurid cetacean, Basilotritus uheni n. gen. n. sp., comes from the late middle Eocene (Bartonian) of Ukraine. It is the earliest dated record of a cetacean from Eastern Europe. The tympanic bulla of Basilotritus uheni shares basilosaurid synapomorphies but possesses unusual traits inherited from protocetids. Cetaceans related to Basilotritus uheni and referred to as Eocetus or “Eocetus” have been recorded from Africa, Europe, North America and South America. “Eocetus” wardii from North America is recombined as Basilotritus wardii. Platyosphys paulsonii and Platyosphys einori from Ukraine are considered as nomina dubia; specimens prior referred to as Platyosphys sp. are similar or related to Basilotritus. Other records of the Eocene cetaceans from Ukraine and south Russia are identified as Basilotritus or related genera. Early basilosaurids are demonstrated to be a paraphyletic, morphologically and geographically diverse group of the genera that colonized the world ocean as late as in Bartonian age and were probably the ancestors of Neoceti, as well as of more derived basilosaurids.
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Mayorga, Luis Felipe S. P., Ralph E. T. Vanstreels, Renata C. C. Bhering, Natália Mamede, Luiz M. B. Costa, Flavia C. F. Pinheiro, Luciano W. D. Reis, et al. "Strandings of cetaceans on the Espírito Santo coast, southeast Brazil, 1975–2015." ZooKeys 948 (July 13, 2020): 129–52. http://dx.doi.org/10.3897/zookeys.948.50468.
Full textAbstract:
Espírito Santo state is located on the eastern margin of Brazil, in a transitional tropical-subtropical area (18°S–21°S) dominated by oligotrophic waters. With the exception of humpback whales (Megaptera novaeangliae), the cetacean community of Espírito Santo has been understudied. In addition to the chronic impacts from fisheries, marine pollution, urban development, and coastal habitat degradation, in November 2015 the cetacean communities of Espírito Santo were challenged by the greatest environmental disaster in Brazil’s history. The Mariana dam disaster caused 60 million cubic meters of mining waste to be washed into the Doce River, which ultimately flowed to the coastal waters of Espírito Santo, with a high concentration of heavy metals. This study reviews and updates information on cetacean strandings in the state of Espírito Santo (excluding humpback whales) prior to this disaster. From 1975 to September 2015, there were 461 recorded cetacean strandings, representing 20 species. An average 1.18 strandings per 100 km per month were recorded since a state-wide daily beach survey program was implemented in October 2010, contrasting with the 0.14 strandings per 100 km per month in previous years. Six species comprised the majority (94.7%) of stranding events: Guiana dolphin (Sotalia guianensis), Franciscana (Pontoporia blainvillei), rough-toothed dolphin (Steno bredanensis), bottlenose dolphin (Tursiops truncatus), sperm whale (Physeter macrocephalus), and melon-headed whale (Peponocephala electra). Oceanic cetaceans stranded most frequently on the southern portion of Espírito Santo, where the continental platform is narrower, whereas the strandings of coastal cetaceans such as Guiana dolphins and Franciscanas were concentrated near estuaries, especially the Doce River. This is particularly concerning in face of the Mariana dam disaster, which drastically altered the estuarine and coastal environment associated with the Doce River.
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Lammers, Marc, Eden J. Zang, Anke Kügler, Jonathan Martinez, Karlina Merkens, and Leila Hatch. "Cetacean acoustic monitoring across the Hawaiian archipelago: Building on Whitlow Au’s legacy." Journal of the Acoustical Society of America 151, no. 4 (April 2022): A74. http://dx.doi.org/10.1121/10.0010702.
Full textAbstract:
The Hawaiian islands are home to more than 20 species of cetaceans and are the principal breeding ground of the north Pacific humpback whale population. The archipelago stretches more than 2500 km from Hawaii Island to Kure Atoll, creating a significant challenge for monitoring the occurrence and distribution of cetaceans across such a vast range. To meet this challenge, the National Oceanic and Atmospheric Administration and the U.S. Navy have been engaged in a three-year effort to monitor the marine soundscape of the Hawaiian archipelago known as the SanctSound Project. Bottom-moored acoustic recorders were deployed at multiple locations across the Hawaiian Islands Humpback Whale National Marine Sanctuary and the Papahānaumokuākea Marine National Monument to examine the occurrence of humpback whales and odontocetes based on the relative prevalence of their acoustic signaling. Anthropogenic sound sources were also studied to understand how these co-occur with cetaceans. Substantial spatial and temporal variability was observed in the prevalence of whale song and dolphin acoustic activity across locations with high cetacean presence sometimes overlapped with elevated anthropogenic activity. This work helps expand our understanding of how cetaceans use the archipelago and builds on the legacy of Whitlow Au, who pioneered cetacean acoustic monitoring in Hawaii.
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Parsons, E. C. M. "Strandings of Small Cetaceans in Hong Kong Territorial Waters." Journal of the Marine Biological Association of the United Kingdom 78, no. 3 (August 1998): 1039–42. http://dx.doi.org/10.1017/s0025315400045021.
Full textAbstract:
Since official records were first initiated in 1973, there have been reports of 154 small cetacean strandings in Hong Kong territorial waters. The species Neophocaena phocaenoides (finless porpoise) and Sousa chinensis (Indo-Pacific hump-backed dolphin) accounted for 77% of these strandings. There are seasonal peaks in the number of reported strandings: Sousa chinensis is more frequently reported during the summer monsoon season and Neophocaena phocaenoides is more frequent in the winter. Almost a third of all finless porpoises stranded were calves. The number of reported small cetacean strandings in Hong Kong has increased dramatically in recent years; partially due to an increasing awareness of local cetaceans and possibly due to escalating levels of human disturbance and anthropogenic pollution.