Ridgway, S. H., and R. J. Harrison, (eds.). HANDBOOK OF MARINE MAMMALS, VOLUME 1: THE WALRUS, SEA LIONS, FUR SEALS, AND SEA OTTER. Academic Press, London, xiv + 235 pp., 1981. Price $35.50. volume 2: seals, xv + 359 pp., 1981. Price $48.50

1982 ◽  
Vol 63 (4) ◽  
pp. 721-723
Author(s):  
C. E. Ray
1986 ◽  
Vol 64 (2) ◽  
pp. 279-284 ◽  
Author(s):  
D. M. Lavigne ◽  
S. Innes ◽  
G. A. J. Worthy ◽  
K. M. Kovacs ◽  
O. J. Schmitz ◽  
...  

A critical review of metabolic rate determinations for pinnipeds (seals, sea lions, fur seals, and walrus) and cetaceans (whales, dolphins, and porpoises) does not support the widely accepted generalization that they have higher metabolic rates than terrestrial mammals of similar size. This finding necessitates a rethinking of the thermoregulatory adaptations of these marine mammals for an aquatic existence and has important implications in comparative studies of mammals, which frequently omit marine forms because they are perceived to be "different" from other mammals. It also suggests that numerous studies have overestimated food consumption by marine mammal populations.


2020 ◽  
Author(s):  
Gisela Heckel ◽  
◽  
M.G. Ruiz Mar ◽  
Y. Schramm ◽  
U. Gorter

Marine mammals are a group of charismatic megafauna, capable of awakening fascination in most people, which makes them especially visible when natural resources or ecosystems are exploited, as is the case with the generation of energy using the sea. There are 131 species of marine mammals in the world, including whales, dolphins, sea lions, seals, walruses, sea otters, polar bears, manatees and dugongs. Mexico’s marine environment is megadiverse, with 38 cetacean species (eight mysticeti or baleen whale species, 30 odontoceti or toothed whale species, dolphins and porpoises), four pinnipeds (two seal species and two sea lion species), one sea otter sub-species and one manatee subspecies (


AJIL Unbound ◽  
2017 ◽  
Vol 111 ◽  
pp. 272-276
Author(s):  
Jérôme de Hemptinne

In times of war, the first instinct is to relieve the suffering of human beings. Environmental and animal interests are always pushed into the background. However, warfare strongly affects natural resources, including animals, which makes animal issues a matter of great concern. Certain species have been vanishing at a rapid rate because of wars, often with disastrous effects on the food chain and on the ecological balance. Indeed, belligerents rarely take into account the adverse consequences of their military operations on animals. They even take advantage of the chaotic circumstances of war in order to poach protected species and to engage in the trafficking of expensive animal products. While generating billions of dollars each year, such poaching and trafficking allows armed groups to grow and to reinforce their authority over disputed territory. States have also trained, and continue to train, certain animals—principally marine mammals such as bottlenose dolphins and California sea lions—to perform military tasks, like ship and harbor protection, or mine detection and clearance. Millions of horses, mules, donkeys, camels, dogs, and birds are obliged to serve on various fronts (transport, logistics, or communications) and become particularly vulnerable targets.


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.


2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Monique Ladds ◽  
David Rosen ◽  
Carling Gerlinsky ◽  
David Slip ◽  
Robert Harcourt

Abstract Physiology places constraints on an animal’s ability to forage and those unable to adapt to changing conditions may face increased challenges to reproduce and survive. As the global marine environment continues to change, small, air-breathing, endothermic marine predators such as otariids (fur seals and sea lions) and particularly females, who are constrained by central place foraging during breeding, may experience increased difficulties in successfully obtaining adequate food resources. We explored whether physiological limits of female otariids may be innately related to body morphology (fur seals vs sea lions) and/or dictate foraging strategies (epipelagic vs mesopelagic or benthic). We conducted a systematic review of the increased body of literature since the original reviews of Costa et al. (When does physiology limit the foraging behaviour of freely diving mammals? Int Congr Ser 2004;1275:359–366) and Arnould and Costa (Sea lions in drag, fur seals incognito: insights from the otariid deviants. In Sea Lions of the World Fairbanks. Alaska Sea Grant College Program, Alaska, USA, pp. 309–324, 2006) on behavioural (dive duration and depth) and physiological (total body oxygen stores and diving metabolic rates) parameters. We estimated calculated aerobic dive limit (cADL—estimated duration of aerobic dives) for species and used simulations to predict the proportion of dives that exceeded the cADL. We tested whether body morphology or foraging strategy was the primary predictor of these behavioural and physiological characteristics. We found that the foraging strategy compared to morphology was a better predictor of most parameters, including whether a species was more likely to exceed their cADL during a dive and the ratio of dive time to cADL. This suggests that benthic and mesopelagic divers are more likely to be foraging at their physiological capacity. For species operating near their physiological capacity (regularly exceeding their cADL), the ability to switch strategies is limited as the cost of foraging deeper and longer is disproportionally high, unless it is accompanied by physiological adaptations. It is proposed that some otariids may not have the ability to switch foraging strategies and so be unable adapt to a changing oceanic ecosystem.


2016 ◽  
Vol 187 (1) ◽  
pp. 29-50 ◽  
Author(s):  
David A. S. Rosen ◽  
Allyson G. Hindle ◽  
Carling D. Gerlinsky ◽  
Elizabeth Goundie ◽  
Gordon D. Hastie ◽  
...  

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