Endoparasite survey of free-swimming baleen whales (Balaenoptera musculus, B. physalus, B. borealis) and sperm whales (Physeter macrocephalus) using non/minimally invasive methods

2015 ◽  
Vol 115 (2) ◽  
pp. 889-896 ◽  
Author(s):  
Carlos Hermosilla ◽  
Liliana M. R. Silva ◽  
Sonja Kleinertz ◽  
Rui Prieto ◽  
Monica A. Silva ◽  
...  
1985 ◽  
Vol 63 (6) ◽  
pp. 1402-1409 ◽  
Author(s):  
Donald F. McAlpine

Size and growth of heart, liver, and kidneys in fin (Balaenoptera physalus), sei (B. borealis), and sperm (Physeter macrocephalus) whales taken commercially off Iceland during the 1980 season are compared and examined relative to organ weights for terrestrial mammals. In agreement with the work of previous investigators, the sperm whale is shown to have a relatively smaller heart. However, contrary to previous analysis, fin and sei whales are shown to have relative heart sizes not radically different from those of terrestrial mammals. It is suggested that the differences in relative heart size between the baleen and toothed whales are a reflection of the greater swimming speeds that the baleen whales are capable of attaining. This analysis confirms that marine cetaceans have relatively much larger livers than terrestrial mammals and that they also appear to have relatively larger kidneys. The results presented here, however, show fin, sei, and sperm whales to have relative kidney sizes less than half as great as those given in previous analyses. Growth gradients in the three organs show a distinct pattern of divergence between sperm (Odontocete) and fin and sei (Mysticete) whales.


2021 ◽  
Author(s):  
Stefanie P. Glaeser ◽  
Liliana M. R. Silva ◽  
Rui Prieto ◽  
Mónica A. Silva ◽  
Angel Franco ◽  
...  

AbstractLarge baleen and toothed whales play crucial ecological roles in oceans; nonetheless, very little is known about their intestinal microbiomes. Based on striking differences in natural history and thus in feeding behaviours, it can be expected that intestinal microbiomes of large baleen whales and toothed whales are different. To test this hypothesis, the phylogenetic composition of faecal microbiomes was investigated by a 16S rRNA gene amplicon sequence–based approach for Bacteria and Archaea. Faecal samples from free-ranging large whales collected off the Azores Archipelago (Portugal) were used, comprising 13 individual baleen whales (one sei, two blue and ten fin whales) and four sperm whales. The phylogenetic composition of the Bacteria faecal microbiomes of baleen and toothed whales showed no significant differences at the phylum level. However, significant differences were detected at the family and genus levels. Most abundant phyla were Firmicutes, Bacteroidetes, Proteobacteria, Tenericutes and Spirochaeta. Few highly abundant bacterial genera were identified as key taxa with a high contribution to differences among baleen and toothed whales microbiomes. Only few archaeal sequences were detected, primarily Methanomassiliicoccales representing potential methanogenic Archaea. This is the first study that directly compares the faecal bacterial and archaeal microbiomes of free-ranging baleen and toothed whales which represent the two parvorders of Cetacea which members are fully aquatic large mammals which were evolutionary split millions of years ago.


2021 ◽  
Vol 9 (4) ◽  
pp. 444
Author(s):  
Charlotte Curé ◽  
Saana Isojunno ◽  
Marije L. Siemensma ◽  
Paul J. Wensveen ◽  
Célia Buisson ◽  
...  

Controlled exposure experiments (CEEs) have demonstrated that naval pulsed active sonar (PAS) can induce costly behavioral responses in cetaceans similar to antipredator responses. New generation continuous active sonars (CAS) emit lower amplitude levels but more continuous signals. We conducted CEEs with PAS, CAS and no-sonar control on free-ranging sperm whales in Norway. Two panels blind to experimental conditions concurrently inspected acoustic-and-movement-tag data and visual observations of tagged whales and used an established severity scale (0–9) to assign scores to putative responses. Only half of the exposures elicited a response, indicating overall low responsiveness in sperm whales. Responding whales (10 of 12) showed more, and more severe responses to sonar compared to no-sonar. Moreover, the probability of response increased when whales were previously exposed to presence of predatory and/or competing killer or long-finned pilot whales. Various behavioral change types occurred over a broad range of severities (1–6) during CAS and PAS. When combining all behavioral types, the proportion of responses to CAS was significantly higher than no-sonar but not different from PAS. Responses potentially impacting vital rates i.e., with severity ≥4, were initiated at received cumulative sound exposure levels (dB re 1 μPa2 s) of 137–177 during CAS and 143–181 during PAS.


1988 ◽  
Vol 45 (10) ◽  
pp. 1736-1743 ◽  
Author(s):  
Julia Mullins ◽  
Hal Whitehead ◽  
Linda S. Weilgart

During June 1986, two male sperm whales, Physeter macrocephalus, on the Scotian Shelf were tracked by listening for their clicks with a directional hydrophone for periods of 12.5 and 7 h, respectively. Each whale travelled along the edge of the shelf at about 2 kn (3.6 km/h), and one whale, on two occasions at least, dived to the ocean floor. After about 30 min underwater, the whales spent approximately 9 min at the surface breathing. When the whales were visible at the surface, they were silent, except on one occasion when "slow clicking" (mean interclick interval of 4.6 s) was heard from Whale 2. While underwater, most of the sound production consisted of "usual clicks" (mean interclick interval 0.96 and 0.69 s for the two whales) interrupted by frequent short silences (mean durations 21.06 and 27.82 s) and occasional "creaks" (with interclick intervals less than 0.2 s) and "slow clicks." No "codas" (stereotyped patterns of clicks) were heard from these two single whales. These results are consistent with the hypotheses that "usual clicks" and "creaks" are used for echolocation and "codas" for communication.


1993 ◽  
Vol 71 (10) ◽  
pp. 1991-1996 ◽  
Author(s):  
Sean C. Smith ◽  
Hal Whitehead

The feeding success of sperm whales off the Galápagos Islands, Ecuador, was examined over 5 study years; 1985, 1987, 1988, 1989, and 1991. A total of 160 days were spent following sperm whales at sea. The defaecation rates of sperm whales were used as an indication of feeding success. The recorded acoustic click rates of sperm whales were used as an indication of aggregative and foraging behaviour. Significant variation in feeding success occurred temporally over periods of days, months, and years. Feeding success also varied spatially with geographic area. Feeding success was inversely related to sea surface temperature (SST). The foraging and associative behaviour of sperm whales also varied with feeding success, SST, and by year. Variations in the feeding success and behaviour of Galápagos sperm whales can likely be attributed to changing oceanographic conditions in the waters surrounding the Galápagos archipelago.


1998 ◽  
Vol 76 (5) ◽  
pp. 886-896 ◽  
Author(s):  
Andrew W Trites ◽  
Daniel Pauly

Generalized survival models were applied to growth curves published for 17 species of cetaceans (5 mysticetes, 12 odontocetes) and 13 species of pinnipeds (1 odobenid, 4 otariids, 8 phocids). The mean mass of all individuals in the population was calculated and plotted against the maximum body length reported for each species. The data showed strong linearity (on logarithmic scales), with three distinct clusters of points corresponding to the mysticetes (baleen whales), odontocetes (toothed whales), and pinnipeds (seals, sea lions, and walruses). Exceptions to this pattern were the sperm whales, which appeared to be more closely related to the mysticetes than to the odontocetes. Regression equations were applied to the maximum lengths reported for 76 species of marine mammals without published growth curves. Estimates of mean body mass were thus derived for 106 living species of marine mammals.


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