Ecology and host relationships of the whale-louse Isocyamus delphini (Amphipoda: Cyamidae) parasitizing long-finned pilot whales (Globicephala melas) off the Faroe Islands (Northeast Atlantic)

1991 ◽  
Vol 69 (1) ◽  
pp. 141-145 ◽  
Author(s):  
J. A. Balbuena ◽  
J. A. Raga

In cooperation with an international research program concerning the biology of the long-finned pilot whale (Globicephala melas) in the Northeast Atlantic, 152 pilot whales taken in the Faroese drive fishery were examined for ectoparasites. The whale-louse Isocyamus delphini was detected on 45(29.61%) of the whales. Four whale groups were established, according to sex and sexual status: immature or pubertal males, mature males, immature females, and mature females. Whale-lice showed over-dispersed distributions on these four whale groups. Prevalence, abundance, and spatial distribution of I. delphini on sexually mature males were significantly different from those on the other whale classes. Heavy infections were only observed on mature males. Behavioral differences between males and females and between adults and juveniles could account for these results. The genital slit was by far the site most preferred by I. delphini. This location seems to be one of the few that offers appropriate shelter for this cyamid.

Parasitology ◽  
1993 ◽  
Vol 106 (3) ◽  
pp. 327-333 ◽  
Author(s):  
J. A. Balbuena ◽  
J. A. Raga

SUMMARYThe intestines of 170 long-finned pilot whales, Globicephala melas, caught off the Faroe Islands (N.E. Atlantic) were examined for helminth parasites. Eight species were detected but only 4 occurred in at least 10% of the sample. No core or recurrent group of species were identified and no correlations between abundances of species were significant. Diversity values were far below those reported for other endotherms. Colonization by helminths was random, whales not being readily colonized. These features point to largely unpredictable, isolationist infracommunities, there being little potential for inter-specific interactions. Older hosts tended to harbour more diverse infracommunities, offering more opportunities for such interactions. Two hypotheses, which might also apply to other cetaceans, are proposed to account for the depauperate helminth communities of the pilot whale: (i) some ancestral helminth species failed to adapt their cycles to the marine habitat and (ii) the hosts' isolation from land prohibited new infections with helminths of mammals.


2016 ◽  
Vol 23 (1) ◽  
pp. 26 ◽  
Author(s):  
Benedict E. Singleton

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


1988 ◽  
Vol 66 (8) ◽  
pp. 1884-1892 ◽  
Author(s):  
Liselotte Wesley Andersen

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.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244561
Author(s):  
Francesca Maura Cassola ◽  
Yann Henaut ◽  
José Rogelio Cedeño-Vázquez ◽  
Fausto Roberto Méndez-de la Cruz ◽  
Benjamín Morales-Vela

The variation in temperament among animals has consequences for evolution and ecology. One of the primary effects of consistent behavioral differences is on reproduction. In chelonians some authors have focused on the study of temperament using different methods. In our research our first aim was i) establish a methodology to determine the degree of boldness among individuals Rhinoclemmys areolata. Our second aim was to ii) determine the role boldness plays during reproduction, with emphasis on courtship and copulation, considering a) the interactions between males and females, and b) competition between males. We used 16 sexually mature individuals of each sex. Males were observed in four different situations and 17 behavioral traits were recorded. We selected 12 traits that allowed us distinguish between the bolder and the shier individuals and found that five behavioral traits were specific for bolder individuals and five others for shier individuals. In a second step, we observed a male in presence of a female and recorded courtship behaviors and breeding attempts. Bolder individuals did not display courtship behaviors and just attempted to copulate. Shier individuals displayed courtship behaviors and copulation attempts were rarely observed. Finally, in the simulations that compared two males in the presence of a female we noticed that bolder individuals displayed courtship behaviors while the shier ones simply ignored the female. Our results first allowed us to determine which methodology is the best to determine temperament in turtles. Secondly, temperament seems to be an important factor in modulating interaction between males and females. Bolder individuals have an advantage during competition and display courtship behaviours only if other males are present. Shier males displayed courtship behaviors and only try to copulate when no competitors were present. These two different temperament-dependant strategies are discussed in terms of ecology, evolution and management.


2019 ◽  
Vol 11 ◽  
Author(s):  
Daniel G. Pike ◽  
Thorvaldur Gunnlaugsson ◽  
Geneviève Desportes ◽  
Bjarni Mikkelsen ◽  
Gísli A. Vikingsson ◽  
...  

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.


Author(s):  
Joanna B. Wong ◽  
Marie Auger-Méthé

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


2015 ◽  
Vol 520 ◽  
pp. 270-285 ◽  
Author(s):  
Katrin S. Hoydal ◽  
Robert J. Letcher ◽  
David A.D. Blair ◽  
Maria Dam ◽  
Christina Lockyer ◽  
...  

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