scholarly journals Species can base their impression of themselves on the number of sensory neurons they have and their IUCN level

2021 ◽  
Author(s):  
aaron goetz
Keyword(s):  
Emotional Disturbance ◽  
Sensory Neurons ◽  
Killer Whale ◽  
Anthropogenic Influence ◽  
Aquatic Species ◽  
Pilot Whale ◽  
Terrestrial Species ◽  
Western Gorilla ◽  
Pilot Whales

Abstract Humans have the most sensory neurons of any terrestrial species, 18.83B, with more than twice as many as the runner up western gorilla. There are three aquatic species with more than humans and seven more with more than the western gorilla. The killer whale with more than twice as many as humans, long-finned and short-finned pilot whale with a little less than twice humans. With that many sensory neurons it would be assumed that those would be the species with the most emotional disturbance from anthropogenic influence. There is no data on killer whale endangerment, and both long and short finned pilot whales are LC, ranking them 23rd and 24th most disturbed species. It is important for us to consider what the species means to them in evaluating what species we should care about, it would be beneficial to base that on what species care about themselves the most.

The Smaller Cetacea of Eastern Canadian Waters

1957 ◽  
Vol 14 (1) ◽  
pp. 83-115 ◽  
Author(s):  
D. E. Sergeant ◽  
H. D. Fisher
Keyword(s):  
Coastal Waters ◽  
Newfoundland And Labrador ◽  
Killer Whale ◽  
Climatic Zone ◽  
Labrador Sea ◽  
Eastern Canada ◽  
Pilot Whale ◽  
Summer Range ◽  
Lagenorhynchus Acutus ◽  
Pilot Whales

An account is given of the known records, distribution and migrations of the smaller Odontocete whales occurring in eastern Canadian waters, with measurements of specimens obtained of the rarer species. The distribution of the abundant pilot whale Globicephala melaena (Traill) has been studied in most detail. The species' summer range includes both the offshore waters of the Labrador Sea and the coastal waters around Newfoundland. The coastal population feeds only on the squid Illex illecebrosus (LeSueur) and its movements inshore in spring and offshore in autumn follow those of the squid over the southwest Grand Bank. In some years a failure of the squid to move shorewards results in a failure of the fisheries for both squid and pilot whales in Newfoundland. The species is known to winter in an oceanic area southeast of the Grand Bank.The white-sided dolphin Lagenorhynchus acutus Gray associates with the pilot whale and apparently inhabits the same climatic zone in these waters, while the white-beaked dolphin L. albirostris Gray is found in somewhat colder waters. The killer whale Grampus orca (L.) migrates northwards in spring along the Newfoundland and Labrador coasts, its migration coinciding with that of the rorquals.New records for the waters of eastern Canada, extending the known range of each, are given for Mesoplodon bidens, Tursiops truncatus, Lagenorhynchus albirostris and Lagenorhynchus acutus.

scholarly journals Love-iathan, the meat-whale and hidden people: ordering Faroese pilot whaling

2016 ◽  
Vol 23 (1) ◽  
pp. 26 ◽  
Author(s):  
Benedict E. Singleton
Keyword(s):  
News Item ◽  
Faroe Islands ◽  
Political Ontology ◽  
Pilot Whale ◽  
Environmental Dispute ◽  
Pilot Whales ◽  
Ocean Environment

A key question in any environmental dispute is the nature of what is under discussion. 'Cosmopolitics' – political battles over the form of reality – are a feature of many environmental clashes. This article focuses on one such clash: during the summer of 2014, grindadráp – the iconic practice of driving pilot whales for meat – was the big news item in the Faroe Islands. More accurately, a conservation campaign by the controversial group Sea Shepherd Conservation Society (SSCS), Operation Grindstop 2014, garnered most attention. Aiming to stop or at least disrupt the 'barbaric' and 'sadistic' grindadráp, SSCS were involved in several confrontations with Faroese authorities and publicly engaged with Faroese pro-whaling advocates in several discussions that were seemingly fruitless. Based on 3 months fieldwork during the campaign, this article describes a 'political ontology' of Grindstop 2014. What emerged was a 'hybrid' born of a clash between two fundamentally dissonant systems of ordering, which structured and were reinforced by various practices, both discursive and material. Activists on both sides were engaged in a cosmopolitical struggle to decisively enact their orderings, creating alternative stories of whales, Faroese whaling, the ocean environment and modernity. The aim is to understand what happened when these orderings met. This article argues that throughout the summer these two orderings moved apart, consequently hiding the diversity of opinion and discussion within Faroese society around grindadráp. As such, alternative orderings of grindadráp were suppressed, notably those voiced by Faroese activists arguing that the practice should cease because of the high levels of toxins in pilot whale meat.Key words: Faroe Islands, whaling, political ontology, cosmopolitics

Electrophoretic differentiation among local populations of the long-finned pilot whale, Globicephala melaena, at the Faroe Islands

1988 ◽  
Vol 66 (8) ◽  
pp. 1884-1892 ◽  
Author(s):  
Liselotte Wesley Andersen
Keyword(s):  
Reproductive Isolation ◽  
Muscle Tissue ◽  
Gel Electrophoresis ◽  
Faroe Islands ◽  
Starch Gel Electrophoresis ◽  
Pilot Whale ◽  
Local Populations ◽  
Starch Gel ◽  
Pilot Whales ◽  
Polymorphic Enzymes

Enzyme variation within and between nine schools of long-finned pilot whales, Globicephala melaena, caught at the Faroe Islands, was examined by starch gel electrophoresis. Twenty-seven enzymes were investigated, representing 41 loci, of which three were polymorphic. The polymorphic enzymes were analyzed in either liver or muscle tissue from 628 specimens. No heterogeneity within the schools was observed, while significant differences in allele frequencies between schools were detected by a multilocus G-test. This result indicated some degree of reproductive isolation.

scholarly journals Calling under pressure: short-finned pilot whales make social calls during deep foraging dives

2011 ◽  
Vol 278 (1721) ◽  
pp. 3017-3025 ◽  
Author(s):  
Frants H. Jensen ◽  
Jacobo Marrero Perez ◽  
Mark Johnson ◽  
Natacha Aguilar Soto ◽  
Peter T. Madsen
Keyword(s):  
Sound Production ◽  
Energy Content ◽  
Ambient Pressure ◽  
Pilot Whale ◽  
Communication Signals ◽  
Deep Diving ◽  
Social Species ◽  
Air Supply ◽  
Social Calls ◽  
Pilot Whales

Toothed whales rely on sound to echolocate prey and communicate with conspecifics, but little is known about how extreme pressure affects pneumatic sound production in deep-diving species with a limited air supply. The short-finned pilot whale ( Globicephala macrorhynchus ) is a highly social species among the deep-diving toothed whales, in which individuals socialize at the surface but leave their social group in pursuit of prey at depths of up to 1000 m. To investigate if these animals communicate acoustically at depth and test whether hydrostatic pressure affects communication signals, acoustic DTAGs logging sound, depth and orientation were attached to 12 pilot whales. Tagged whales produced tonal calls during deep foraging dives at depths of up to 800 m. Mean call output and duration decreased with depth despite the increased distance to conspecifics at the surface. This shows that the energy content of calls is lower at depths where lungs are collapsed and where the air volume available for sound generation is limited by ambient pressure. Frequency content was unaffected, providing a possible cue for group or species identification of diving whales. Social calls may be important to maintain social ties for foraging animals, but may be impacted adversely by vessel noise.

Ecological adaptations and morphological variation in the posterior disc of larvae of Sciomyzidae (Diptera)

1990 ◽  
Vol 68 (3) ◽  
pp. 517-521 ◽  
Author(s):  
Jean-Claude Vala ◽  
Charles Gasc
Keyword(s):  
Morphological Variation ◽  
Feeding Behaviour ◽  
Posterior Part ◽  
Aquatic Species ◽  
Terrestrial Species ◽  
Ecological Adaptations ◽  
Morphological Aspects

The posterior part of segment 12 in the larvae of Sciomyzidae, commonly called the posterior disc, has four morphological aspects related to habitat and feeding behaviour. According to the variations observed, the following ecological categories can be used: (i) supra-aquatic species have well-developed float hairs (hydrofuge interspiracular processes) and long triangular peripheral lobes of the disc; (ii) semi-aquatic species have moderately developed float hairs and short triangular lobes; (iii) intermediate terrestrial species have very short float hairs and circular lobes; (iv) true terrestrial species have vestigial, scalelike float hairs and hemispherical lobes.

scholarly journals Ontogenetic and inter-elemental osteohistological variability in the leopard tortoise Stigmochelys pardalis

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e8030 ◽  
Author(s):  
Alexander Edward Botha ◽  
Jennifer Botha
Keyword(s):  
Bone Resorption ◽  
Hind Limb ◽  
Life History Traits ◽  
Histological Analysis ◽  
Fundamental System ◽  
Adult Stage ◽  
Aquatic Species ◽  
Terrestrial Species ◽  
Limb Bones ◽  
Hind Limbs

Testudines are a group of reptiles characterized by the presence of a shell covered by keratinous shields. Stigmochelys pardalis is the most widely distributed terrestrial testudine in southern Africa. Although relatively common with some life history traits being well known, the growth of this species has yet to be studied in any detail. The bone microanatomy of this clade differs from that found in other amniotes, where terrestrial species tend to display characteristics normally seen in aquatic species and vice versa. A detailed histological analysis of the limb bones of S. pardalis reveals extensive variation through ontogeny. Cortical bone becomes increasingly thicker through ontogeny and is finally resorbed in the late sub-adult stage, resulting in a thin cortex and a large infilled medullary cavity. The predominant bone tissues are parallel-fibred and lamellar-zonal for the forelimbs and hind limbs respectively. The oldest individual displayed an External Fundamental System indicating that the growth rate had decreased substantially by this stage. Variability is prevalent between the forelimb and hind limb as well as between early and late sub-adults Forelimb elements exhibit characteristics such as faster growing parallel-fibered bone tissue, slightly higher vascularization and a predominance of annuli over Lines of Arrested Growth (LAG) compared to the hind limb which exhibits poorly vascularized, slower growing lamellar-zonal bone interrupted by LAGs. These differences indicate that the forelimb grew more rapidly than the hind limb, possibly due to the method of locomotion seen in terrestrial species. The extensive bone resorption that occurs from the early sub-adult stage destroys much of the primary cortex and results in a significantly different ratio of inner and outer bone diameter (p = 3.59 × 10­−5; df = 28.04) as well as compactness (p = 2.91 × 10­−5; df = 31.27) between early and late sub-adults. The extensive bone resorption seen also destroys the ecological signal and infers an aquatic lifestyle for this species despite it being clearly terrestrial. This supports the results of other studies that have found that using bone microanatomy to determine lifestyle in testudines does not produce accurate results.

Social structure of long-finned pilot whales (Globicephala melas) off northern Cape Breton Island, Nova Scotia

Behaviour ◽  
2017 ◽  
Vol 154 (5) ◽  
pp. 509-540 ◽  
Author(s):  
J.F. Augusto ◽  
T.R. Frasier ◽  
H. Whitehead
Keyword(s):  
Social Structure ◽  
Pilot Whale ◽  
Detailed Model ◽  
Cape Breton Island ◽  
Long Term Stability ◽  
Cape Breton ◽  
Northern Cape ◽  
Pilot Whales ◽  
Average Size ◽  
Social Units

Cetacean social structures include fluid and stable elements. Long-finned pilot whales (Globicephala melas) live in units that interact forming labile groups. In this study conducted off Cape Breton Island, between 1998–2011, we confirm unit membership predicts associations between individuals. We determine how units are structured and interact. We delineated 21 nearly-stable social units, with an average 7 members. For units where multiple individuals are sexed, both sexes are present. Most units showed long-term stability, while one showed evidence of splitting. Three units shared individuals with the largest unit (K, average size = 29). Splitting is likely triggered by size and difficulties maintaining associations between all individuals. Pilot whales face many pressures driving sociality at a range of temporal and social scales producing a multilevel society. While we have produced a more detailed model of long-finned pilot whale social structure, there are still unanswered questions, particularly whether units are strict matrilines.

scholarly journals Ecological niches of three teuthophageous odontocetes in the northwestern Mediterranean Sea

Ocean Science ◽  
2008 ◽  
Vol 4 (1) ◽  
pp. 49-59 ◽  
Author(s):  
E. Praca ◽  
A. Gannier
Keyword(s):  
Mediterranean Sea ◽  
Sperm Whale ◽  
Ecological Niches ◽  
Sperm Whales ◽  
Ligurian Sea ◽  
Data Set ◽  
Pilot Whale ◽  
Northwestern Mediterranean Sea ◽  
Pilot Whales ◽  
Northwestern Mediterranean

Abstract. In the northwestern Mediterranean Sea, sperm whales, pilot whales and Risso's dolphins prey exclusively or preferentially on cephalopods. In order to evaluate their competition, we modelled their habitat suitability with the Ecological Niche Factor Analysis (ENFA) and compared their ecological niches using a discriminant analysis. We used a long term (1995–2005) small boat data set, with visual and acoustic (sperm whale) detections. Risso's dolphin had the shallowest and the more spatially restricted principal habitat, mainly located on the upper part of the continental slope (640 m mean depth). With a wider principal habitat, at 1750 m depth in average, the sperm whale used a deeper part of the slope as well as the closest offshore waters. Finally, the pilot whale has the most oceanic habitat (2500 m mean depth) mainly located in the central Ligurian Sea and Provençal basin. Therefore, potential competition for food between these species may be reduced by the differentiation of their habitats.

scholarly journals Estimates of the relative abundance of long-finned pilot whales (Globicephala melas) in the Northeast Atlantic from 1987 to 2015 indicate no long-term trends

2019 ◽  
Vol 11 ◽  
Author(s):  
Daniel G. Pike ◽  
Thorvaldur Gunnlaugsson ◽  
Geneviève Desportes ◽  
Bjarni Mikkelsen ◽  
Gísli A. Vikingsson ◽  
...  
Keyword(s):  
Relative Abundance ◽  
North Atlantic ◽  
Distance Sampling ◽  
Field Methods ◽  
Pilot Whale ◽  
Globicephala Melas ◽  
The North ◽  
Spatial Coverage ◽  
Pilot Whales ◽  
Annual Distribution

North Atlantic Sightings Surveys (NASS) and associated surveys, covering a large but variable portion of the North Atlantic, were conducted in 1987, 1989, 1995, 2001, 2007 and 2015. Previous estimates of long-finned pilot whale (Globicephala melas) abundance, derived using conventional distance sampling (CDS), are not directly comparable to one another because of differing survey coverage, field methods and, in the case of the 1989 NASS, different survey timing. CDS was used to develop indices of relative abundance to determine if pilot whale abundance has changed over the 28-year period from 1987 to 2015. The varying spatial coverage of the surveys is accommodated by delineating common regions that were covered by: i) all 6 surveys, and ii) the 3 largest surveys (1989, 1995, and 2007). These “Index Regions” were divided into East and West subregions, and post-stratification was used to obtain abundance estimates for these index areas only. Estimates are provided using the sightings from the combined platforms for surveys that used double platforms or the primary platform only.Total abundance in the Index Regions, uncorrected for perception or availability biases, ranged from 54,264 (CV=0.48) in 2001 to 253,109 (CV=0.43) in 2015. There was no significant trend in the numbers of individuals or groups in either the 6 or 3 Survey Index Regions, and no consistent trend over the period. Power analyses indicate that negative annual growth rates of -3% to -5% would have been detectible over the entire period. The Index Regions comprise only a portion of the summer range of the species and changes in annual distribution clearly affect the results. Operational changes to the surveys, particularly in defining pilot whale groups, may also have introduced biases. Recommendations for future monitoring of the long-finned pilot whale population are provided.

scholarly journals Using laser photogrammetry to measure long-finned pilot whales (Globicephala melas)

2018 ◽  
Vol 49 (2) ◽  
pp. 269
Author(s):  
Joanna B. Wong ◽  
Marie Auger-Méthé
Keyword(s):  
Body Length ◽  
Small Sample Size ◽  
Total Body Length ◽  
Small Sample ◽  
Ease Of Use ◽  
Pilot Whale ◽  
Globicephala Melas ◽  
Photo Identification ◽  
Dorsal Fin ◽  
Pilot Whales

Knowledge of animal morphometry is important to understanding their ecology. By attaching two parallel lasers to a camera, known as laser photogrammetry (LP), a scale is projected onto photographed animals, allowing measurement of their body. Our primary aims were to test LP precision, and to estimate body length from dorsal-fin dimensions of Globicephala melas. Secondary aims involved demonstrating applications of LP, such as sex and leader determination. Using photographs taken over two-months, we measured dorsal base lengths (DBL) of 194 individuals individually-identified with natural markings. Results indicated 33 individuals were photographed in multiple encounters and eight matched previously-sexed whales. A mean difference of <2.1% between DBL’s of 58% of repeatedly-sighted individuals was found, and whales closer to the boat (<22m) produced more precise measures. The length from the blowhole to anterior insertion of the dorsal fin (BAID) was a better predictor of total body length in stranded whales than DBL, and laser-estimated lengths fell almost all within known pilot whale size. Despite our small sample size, we showed two examples of how LP could be applied in research: (1) males and females had similar DBL (n=8), but large males could be distinguished using DBL; (2) leaders were not necessarily bigger than other individuals in the same cluster (n=4). The ease of use of LP makes it a valuable tool in collecting measurements of body features, especially when coupled with photo-identification. Keywords: laser photogrammetry, morphometrics, measurement, length, Globicephala melas

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