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Diving Mammals

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The ability of diving mammals to forage at depth on a breath hold of air is dependent on gas exchange, both in the lung and in peripheral tissues. Anatomical and physiological adaptations in the respiratory system, cardiovascular system, blood and peripheral tissues contribute to the remarkable breath‐hold capacities of these animals. The end results of these adaptations include efficient ventilation, enhanced oxygen storage, regulated transport and delivery of respiratory gases, extreme hypoxemic/ischemic tolerance, and pressure tolerance. © 2011 American Physiological Society. Compr Physiol 1:447‐465, 2011.

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Figure 1. Figure 1.

Depth and arterial Pn2 profiles of a Weddell seal. Data from reference 60. During this 8‐min dive, samples collected during the first 4 min demonstrated that Pn2 peaked at 2.7 ATA and then declined despite depths as deep as 9.2 ATA (82 m) during sampling. A minimum 80% N2 fraction in the lungs would correspond to an alveolar Pn2 of approximately 7.3 ATA at a depth of 82 m.

Figure 1.

Depth and arterial Pn2 profiles of a Weddell seal. Data from reference 60. During this 8‐min dive, samples collected during the first 4 min demonstrated that Pn2 peaked at 2.7 ATA and then declined despite depths as deep as 9.2 ATA (82 m) during sampling. A minimum 80% N2 fraction in the lungs would correspond to an alveolar Pn2 of approximately 7.3 ATA at a depth of 82 m.

 1. Andrews RD, Jones DR, Williams JD, Thorson PH, Oliver GW, Costa DP, Le Boeuf BJ. Heart rates of northern elephant seals diving at sea and resting on the beach. J Exp Biol 200: 2083–2095, 1997.
 2. Antonini E. Interrelationship between structure and function in hemoglobin and myoglobin. Physiol Rev 45: 123–170, 1965.
 3. Baird RW, Borsani JF, Hanson MB, Tyack PL. Diving and night‐time behavior of long‐finned pilot whales in the Ligurian Sea. Mar Ecol Prog Ser 237: 301–305, 2002.
 4. Baird RW, Webster DL, Schorr GS, McSweeney DJ, Barlow J. Diel variation in beaked whale diving behavior. Mar Mamm Sci 24: 630–642, 2008.
 5. Baker J, Yost CS, Niemann CU. Organ transplantation. In: Miller RD, editor. Miller's Anesthesia. Philadelphia: Elsevier, 2005, p. 2231–2284.
 6. Belanger LF. A study of the histological structure of the respiratory portion of the lungs of aquatic mammals. Am J Anat 67: 437–461, 1940.
 7. Bennett JB, Rostain JC. High pressure nervous syndrome. In: Brubakk AO, Neuman TS, editors. Physiology and Medicine of Diving. Cornwall, MA: Saunders, 2003, p. 323–357.
 8. Blei ML, Conley KE, Kushmerick MJ. Separate measures of ATP utilization and recovery in human skeletal muscle. J Physiol (Cambridge) 465: 203–222, 1993.
 9. Blessing MH. Myoglobin concentration in Platanista indi. Invest Cetacea 4: 91–92, 1972.
 10. Blessing MH. Studies on the concentration of myoglobin in the sea‐cow and porpoise. Comp Physiol Biochem 41A: 475–480, 1972.
 11. Blix AS, Elsner RW, Kjekhus JK. Cardiac output and its distribution through capillaries and A‐V shunts in diving seals. Acta Physiol Scand 118: 109–116, 1983.
 12. Born EW, Knutsen LO. Haul‐out and diving activity of male Atlantic walruses (Odobenus rosmarus) in NE Greenland. J Zool (London) 243: 381–396, 1997.
 13. Bostrom BL, Falhlman A, Jones DR. Tracheal compression delays alveolar collapse during deep diving in marine mammals. Respir Physiol Neurobiol 161: 298–305, 2008.
 14. Bowen WD, Boness DJ, Iverson SJ. Diving behaviour of lactating harbour seals and their pups during maternal foraging trips. Can J Zool 77: 978–988, 1999.
 15. Boyd IL, Bevan RM, Woakes AJ, Butler PJ. Heart rate and behavior of fur seals: Implications for measurement of field energetics. Am J Physiol 276: H844–H857, 1999.
 16. Bryden MM. Body size and composition of elephant seals (Mirounga leonina): Absolute measurements and estimates from bone dimensions. J Zool (London) 167: 265–276, 1972.
 17. Bryden MM, Molyneux GS. Arteriovenous anastomoses in the skin of seals II. The California sea lion (Zalophus californianus) and the northern fur seal (Callorhinus ursinus) (Pinnipedia: Otariidae). Anat Rec 191: 253–260, 1978.
 18. Burns JM, Castellini MA. Physiological and behavioral determinants of the aerobic dive limit in Weddell seal (Leptonychotes weddellii) pups. J Comp Physiol B 166: 473–483, 1996.
 19. Burns JM, Costa DP, Frost K, Harvey JT. Physiological development in juvenile harbor seals. Physiol Biochem Zool 78: 1057–1068, 2005.
 20. Burns JM, Lestyk KC, Hammill MO, Folkow LP, Blix AS. Size and distribution of oxygen stores in harp and hooded seals from birth to maturity. J Comp Physiol B 177: 687–700, 2007.
 21. Butler PJ. Metabolic regulation in diving birds and mammals. Respir Physiol Neurobiol 141: 297–315, 2004.
 22. Butler PJ. Aerobic dive limit. What is it and is it always used properly? Comp Biochem Physiol A 145: 1–6, 2006.
 23. Butler PJ, Jones DR. The physiology of diving of birds and mammals. Physiol Rev 77: 837–899, 1997.
 24. Cabanac AJ, Messelt EB, Folkow LP, Blix AS. The structure and blood‐storing function of the spleen of the hooded seal (Cystophora cristata). J Zool (Lond) 248: 75–81, 1999.
 25. Castellini MA, Costa DP, Huntley A. Hematocrit variation during sleep apnea in elephant seal pups. Am J Physiol 251: R429–R431, 1986.
 26. Castellini MA, Davis RW, Kooyman GL. Blood chemistry regulation during repetitive diving in Weddell seals. Physiol Zool 61: 379–386, 1988.
 27. Castellini MA, Davis RW, Kooyman GL. Diving Behavior of the Weddell Seal: Annual Cycles. Berkeley: University of California Press, 1992, p. 1–54.
 28. Castellini MA, Kooyman GL, Ponganis PJ. Metabolic rates of freely diving Weddell seals: Correlations with oxygen stores, swim velocity, and diving duration. J Exp Biol 165: 181–194, 1992.
 29. Castellini MA, Milsom WK, Berger RJ, Costa DP, Jones DR, Castellini JM, Rea LD. Patterns of respiration and heart rate during wakefulness and sleep in elephant seal pups. Am J Physiol 266: R863–R869, 1994.
 30. Castellini MA, Rea LD, Sanders JL, Castellini JM, Zenteno‐Savin T. Developmental changes in cardiorespiratory patterns of sleep‐associated apnea in northern elephant seals. Am J Physiol 267: R1294–R1301, 1994.
 31. Castellini MA, Somero GN. Buffering capacity of vertebrate muscle: Correlations with potentials for anaerobic function. J Comp Physiol B 143: 191–198, 1981.
 32. Castellini MA, Somero GN, Kooyman GL. Glycolytic enzyme activities in tissues of marine and terrestrial mammals. Physiol Zool 54: 242–252, 1981.
 33. Chilvers BL, Delean S, Gales NJ, Holley DK, Lawler IR, Marsh H, Preen AR. Diving behavior of dugongs, Dugong dugon. J Exp Mar Biol Ecol 304: 203–224, 2004.
 34. Cozzi B, Bagnoli P, Acocella F, Costantino ML. Structure and biomechanical properties of the trachea of the striped dolphin Stenella coeruleoalba: Evidence for evolutionary adaptations to diving. Anal Rec 284: 500–510, 2005.
 35. Craig AB Jr. Depth limits of breath hold diving (an example of Fennology). Respir Physiol 5: 14–22, 1968.
 36. Croll DA, Tershy BR, Hewitt RP, Demer DA, Fiedler PC, Smith SE, Armstrong W, Popp JM, Kiekhefer T, Lopez VR, Urban J, Genmdron D. An integrated approach to the foraging ecology of marine birds and mammals. Deep Sea Res II 45: 1353–1371, 1998.
 37. Cross ER. Taravana. Diving syndrome in the Tuamotu diver. In: Rahn H, Yokoyama T, editors. Physiology of Breath‐Hold Diving and the Ama of Japan Publication 1341. Washington, DC: National Academy of Sciences, National Research Council, 1965, p. 207–219.
 38. Davis RW, Castellini MA, Kooyman GL, Maue R. Renal GFR and hepatic blood flow during voluntary diving in Weddell seals. Am J Physiol 245: 743–748, 1983.
 39. Davis RW, Kanatous SB. Convective oxygen transport and tissue oxygen consumption in Weddell seals during aerobic dives. J Exp Biol 202: 1091–1113, 1999.
 40. Davis RW, Weihs D. Locomotion in diving elephant seals: Physical and physiological constraints. Philos Trans R Soc B 362: 2141–2150, 2007.
 41. Denison DM, Kooyman GL. The structure and the function of the small airways in pinniped and sea otter lungs. Respir Physiol 17: 1–10, 1973.
 42. Denison DM, Warrell DA, West JB. Airway structure and alveolar emptying in the lungs of sea lions and dogs. Respir Physiol 13: 252–260, 1971.
 43. Dolar MLL, Suarez P, Ponganis PJ, Kooyman GL. Myoglobin in pelagic small cetaceans. J Exp Biol 202: 227–236, 1999.
 44. Drabek CM, Kooyman GL. Bronchial morphometry of the upper conductive zones of four odontocete cetaceans. In: Harrison RJ, editor. Research in Dolphins. Oxford: Oxford University Press, 1986, p. 109–127.
 45. Duran WN, Renkin EM. Oxygen consumption and blood flow in resting mammalian skeletal muscle. Am J Physiol 226: 173–177, 1974.
 46. Dyck MG, Romberg S. Observations of a wild polar bear (Ursus maritimus) successfully fishing Arctic charr (salvelinus alpinus) and fourhorn sculpin (Myxocephalus quadricornis). Polar Biol 30: 1625–1628, 2007.
 47. Eckenhoff RC, Olstad CS, Carrod G. Human dose‐response relationship for decompression and endogenous bubble formation. J Appl Physiol 69: 914–918, 1990.
 48. Elsner R. Heart rate response in forced versus trained experimental dives of pinnipeds. Hvalradets Skrifter 48: 24–29, 1965.
 49. Elsner R. Cardiovascular adjustments to diving. In: Andersen HT, editor. The Biology of Marine Mammals. New York: Academic Press, 1969, p. 117–145.
 50. Elsner R, Franklin DL, Van Citters RL, Kenney DW. Cardiovascular defense against asphyxia. Science 153: 941–949, 1966.
 51. Elsner R, Kenney DW, Burgess K. Bradycardia in the trained dolphin. Nature 212: 407, 1966.
 52. Elsner R, Oyasaetr S, Almaas R, Sauagstad OD. Diving seals, ischemia‐reperfusion, and oxygen radicals. Comp Biochem Physiol A 119: 975–980, 1998.
 53. Elsner R, Shurley JT, Hammond DD, Brooks RE. Cerebral tolerance to hypoxemia in asphyxiated Weddell seals. Respir Physiol 9: 287–297, 1970.
 54. Elsner RW, Scholander PF, Craig AB, Dimond EG, Irving L, Pilson M, Johansen K, Bradstreet E. A venous blood oxygen reservoir in the diving elephant seal. Physiologist 7: 124, 1964.
 55. Fahlman A, Hooker SK, Olszowka A, Bostrom BL, Jones DR. Estimating the effect of lung collapse and pulmonary shunt on gas exchange during breath‐hold diving: The Scholander and Kooyman legacy. Respir Physiol Neurobiol 165: 28–39, 2009.
 56. Fahlman A, Olszowka A, Bostrom B, Jones DR. Deep diving mammals: Dive behavior and circulatory adjustments contribute to bends avoidance. Respir Physiol Neurobiol 153: 66–77, 2006.
 57. Fahlman A, Schmidt A, Jones DR, Bostrom BL, Handrich Y. To what extent might N2 limit dive performance in king penguins? J Exp Biol 210: 3344–3355, 2007.
 58. Fahlman A, Svard C, Rosen DA, Jones DR, Trites AW. Metabolic costs of foraging and management of O2 and CO2 stores in Steller sea lions. J Exp Biol 211: 3573–3580, 2008.
 59. Falke KJ, Busch T, Hoffman O, Liggins GC, Liggins J, Mohnnaupt R, Roberts JD Jr, Stanek K, Zapol WM. Breathing pattern, CO2 elimination and the absence of exhaled NO in freely diving Weddell seals. Respir Physiol Neurobiol 162: 85–92, 2008.
 60. Falke KJ, Hill RD, Qvist J, Schneider RC, Guppy M, Liggins GC, Hochachka PW, Elliott RE, Zapol WM. Seal lungs collapse during free diving: Evidence from arterial nitrogen tensions. Science 229: 556–558, 1985.
 61. Fedak MA, Pullen MR, Kanwisher J. Circulatory responses of seals to periodic breathing: Heart rate and breathing during exercise and diving in the laboratory and open sea. Can J Zool 66: 53–60, 1988.
 62. Feldkamp SD, DeLong RL, Antonelis GA. Diving patterns of California sea lions, Zalophus californianus. Can J Zool 67: 872–883, 1989.
 63. Fernandez A, Edwards J, Martin V, Rodriguez V, Espinosa de los Monteros A, Herraez P, Castro P, Jaber MR, Arbelo M. “Gas and fat embolic syndrome” involving a mass stranding of beaked whales exposed to anthropogenic sonar signals. J Vet Pathol 42: 446–457, 2005.
 64. Ferretti G, Costa M, Ferrigno M, Grassi B, Marconi C, Lundgren CEG, Cerretelli P. Alveolar gas composition and exchange during deep breath‐hold diving and dry breath holds in elite divers. J Appl Physiol 70: 794–802, 1991.
 65. Ferrigno M, Lundgren CE. Breath‐hold diving. In: Brubakk AO, Neuman TS, editors. Physiology and Medicine of Diving. Edinburgh, UK: Saunders, 2003, p. 779.
 66. Folkow LP, Blix AS. Diving behaviour of hooded seals (Cystophora cristata) in the Greenland and Norwegian seas. Polar Biol 22: 61–74, 1999.
 67. Folkow LP, Ramirez J‐M, Ludvigsen S, Ramirez N, Blix AS. Remarkable neuronal hypoxia tolerance in the deep‐diving adult hooded seal (Cystophora cristata). Neurosci Lett 446: 147–150, 2008.
 68. Foot NJ, Orgeig S, Daniels CB. The evolution of a physiological system: The pulmonary surfactant system in diving mammals. Respir Physiol Neurobiol 154: 118–138, 2006.
 69. Fowler SL, Costa DP, Arnould JPY, Gales NJ, Burns JM. Ontogeny of oxygen stores and physiological diving capability in Australian sea lions. Functional Ecology 21: 922–935, 2007.
 70. Fujise Y, Hidaka H, Tatsukawa R, Miyazaki N. External measurements and organ weights of five Weddell seals (Leptonychotes weddellii) caught near Syowa Station. Antarctic Rec (Tokyo) 85: 96–101, 1985.
 71. Fuson AL, Cowan DF, Kanatous SB, Polasek LK, Davis RW. Adaptations to hypoxia in the heart, kidneys, and splanchnic organs of harbor seals (Phoca vitulina). J Exp Biol 206: 4139–4154, 2003.
 72. Gales NJ, Mattlin RH. Summer diving behaviour of lactating New Zealand sea lions, Phocarctos hookeri. Can J Zool 75: 1695–1706, 1997.
 73. Gallivan GJ, Best RC. Metabolism and respiration of the Amazonian manatee (Trichechus inguinis). Physiol Zool 53: 245–253, 1980.
 74. Gallivan GJ, Kanwisher JW, Best RC. Heart rates and gas exchange in the Amazonian manatee (Trichecus manutus) in relation to diving. J Comp Physiol B 156: 415–423, 1986.
 75. Gentry RL, Kooyman GL editors. Fur Seals: Maternal Strategies on Land and at Sea. Princeton, NJ: Princeton University Press, 1986, p. 291.
 76. Grocott MPW, Martin DS, Levett DZH, McMorrow R, Windsor J, Montgomery HE. Arterial blood gases and oxygen content in climbers on Mount Everest. N Engl J Med 360: 140–149, 2009.
 77. Guppy M, Hill RD, Liggins GC, Zapol WM, Hochachka PW. Micro‐computer assisted metabolic studies of voluntary diving of Weddell seals. Am J Physiol 250: 175–187, 1986.
 78. Guyton GP, Stanek KS, Schneider RC, Hochachka PW, Hurford WE, Zapol DG, Zapol WM. Myoglobin‐saturation in free‐diving Weddell seals. J Appl Physiol 79: 1148–1155, 1995.
 79. Halasz NA, Elsner R, Garvie RS. Renal recovery from ischemia: A comparative study of harbor seal and dog kidneys. Am J Physiol 227: 1331–1335, 1974.
 80. Halsey J. Effects of high pressure on the central nervous system. Physiol Rev 62: 1341–1377, 1982.
 81. Hammond JA, Bennett A, Waltom MJ, Hall AJ. Molecular cloning and expression of leptin in gray and harbor seal blubber, bone marrow, and lung and its potential role in marine mammal respiratory physiology. Am J Physiol 289: 545–553, 2005.
 82. Harvey EN, McElroy WD, Whitely AH, Warren GH, Peace DC. Bubble formation in animals, part III. An analysis of gas pressure and hydrostatic tension in cats. J Cell Comp Physiol 24: 117–132, 1944.
 83. Heide‐Jorgensen MP, Bloch D, Stefansson E, Mikkelsen B, Ofstad LH, Dietz R. Diving behaviour of long‐finned pilot whales Globicephalas around the Faroe Islands. Wildl Biol 8: 307–311, 2002.
 84. Hill RD, Schneider RC, Liggins GC, Schuette AH, Elliott RL, Guppy M, Hochachka PW, Zapol WM. Heart rate and body temperature during free diving of Weddell seals. Am J Physiol 253: R344–R351, 1987.
 85. Hindell MA, Slip DJ, Burton HR. The diving behaviour of adult male and female southern elephant seals, Mirounga leonina (Pinnipedia: Phocidae). Aust J Zool 39: 595–619, 1991.
 86. Hochachka PW, Guppy M. Metabolic Arrest and the Control of Biological Time. Cambridge, MA: Harvard University Press, 1987.
 87. Hochachka PW, Liggins GC, Qvist J, Schneider RC, Snider MT, Wonders TR, Zapol WM. Pulmonary metabolism for diving: Conditioning blood for the brain. Science 198: 831–834, 1977.
 88. Hochachka PW, Owen TG, Allen JF, Whittow GC. Multiple end products of anaerobiosis in diving vertebrates. Comp Biochem Physiol B Biochem Mol Biol 50: 17, 1975.
 89. Hogan MC, Bebout DE, Wagner PD. Effect of blood flow reduction on maximal O2 uptake in canine gastrocnemius muscle in situ. J Appl Physiol 74: 1742–1747, 1993.
 90. Hooker SK, Baird RW. Deep‐diving behaviour of the northern bottlenose whale, Hyperoodon ampullatus (Cetacea: Ziphiidae). Proc R Soc Lon B Biol Sci 266: 671–676, 1999.
 91. Hooker SK, Baird RW, Fahlman A. Could beaked whales get the bends? Effect of diving behaviour and physiology on modelled gas exchange for three species: Ziphius cavirostris, Mesoplodon densirostris and Hyperoodon ampullatus. Respir Physiol Neurobiol 167: 235, 2009.
 92. Hooker SK, Miller PJO, Johnson MP, Cox OP, Boyd IL. Ascent exhalations of Antarctic fur seals: A behavioural adaptation for breath‐hold diving? Proc R Soc Lond B Biol Soc 272: 355–363, 2005.
 93. Houser DS, Dankiewicz‐Talmadge LA, Stockard TK, Ponganis PJ. Investigation of the potential for vascular bubble formation in a repetitively diving dolphin. J Exp Biol 213: 52–62, 2010.
 94. Houser DS, Howard R, Ridgway S. Can diving‐induced tissue nitrogen supersaturation increase the chance of acoustically driven bubble growth in marine mammals. J Theor Biol 213: 183–195, 2001.
 95. Hurford WE, Hochachka PW, Schneider RC, Guyton GP, Stanek KS, Zapol DG, Liggins GC, Zapol WM. Splenic contraction, catecholamine release, and blood volume redistribution during diving in the Weddell seal. J Appl Physiol 80: 298–306, 1996.
 96. Hurley JA, Costa DP. Standard metabolic rate at the surface and during trained submersions in adult California sea lions (Zalophus californianus). J Exp Biol 204: 3273–3281, 2001.
 97. Jaquet N, Dawson S, Slooten E. Seasonal distribution and diving behaviour of male sperm whales off Kaikoura: Foraging implications. Can J Zool 78: 407–419, 2000.
 98. Jepson PD, Arbelo M, Deaville R, Patterson IAP, Castro P, Baker JD, Degollada E, Ross HM, Herraez P, Pocknell AM, Rodriquez F, Howiell FE, Espinosa A, Reid RJ, Jabert JR, Martin V, Cunningham AA, Fernandez A. Gas‐bubble lesions in stranded cetaceans. Nature 425: 575–576, 2003.
 99. Jobsis PD, Ponganis PJ, Kooyman GL. Effects of training on forced submersion responses in harbor seals. J Exp Biol 204: 3877–3885, 2001.
 100. Kanatous SB, Davis RW, Watson R, Polasek L, Willliams TM, Mathieu‐Costello O. Aerobic capacities in the skeletal muscles of Weddell seals: Key to longer dive durations? J Exp Biol 205: 3601–3608, 2002.
 101. Kanatous SB, DiMichele LV, Cowan DF, Davis RW. High aerobic capacities in the skeletal muscles of pinnipeds: Adaptations to diving hypoxia. J Appl Physiol 86: 1247–1256, 1999.
 102. Kanatous SB, Elsner R, Mathieu‐Costello O. Muscle capillary supply in harbor seals. J Appl Physiol 90: 1919–1926, 2001.
 103. Kanatous SB, Hawke TJ, Trumble SJ, Pearson LE, Watson RR, Garry DJ, Williams TM, Davis RW. The ontogeny of aerobic and diving capacity in the skeletal muscles of Weddell seals.. J Exp Biol 211: 2559–2565, 2008.
 104. Kerem D, Elsner RW. Cerebral tolerance to asphyxial hypoxia in the harbor seal. Respir Physiol 19: 188–200, 1973.
 105. Kerem DH, Hammond DD, Elsner R. Tissue glycogen levels in the Weddell seals (Leptonychotes weddelli): A possible adaptation to asphyxial hypoxia. Comp Biochem Physiol 45: 731–736, 1973.
 106. Kerem DH, Kylstra JA, Saltzman HA. Respiratory flow rates in the sea lion. Undersea Biomed Res 2: 20–27, 1975.
 107. King JE. Seals of the World. Ithaca, NY: Cornell University Press, 1983, p. 240.
 108. Kooyman GL. Deep diving behaviour and effects of pressure in reptiles, birds, and mammals. Symp Soc Exp Biol 26: 295–311, 1972.
 109. Kooyman GL. Respiratory adaptations in marine mammals. Am Zool 13: 457–468, 1973.
 110. Kooyman GL. Physiology without restraint in diving mammals. Mar Mamm Sci 1: 166–178, 1985.
 111. Kooyman GL. Diverse Divers Physiology and Behavior. Berlin: Springer‐Verlag, 1989, p. 200.
 112. Kooyman GL, Andersen HT. Deep diving. In: Andersen HT, editors. The Biology of Marine Mammals. New York: Academic Press, 1968, p. 65–94.
 113. Kooyman GL, Campbell WB. Heart rate in freely diving Weddell seals (Leptonychotes weddellii). Comp Biochem Physiol 43: 31–36, 1973.
 114. Kooyman GL, Castellini MA, Davis RW, Maue RA. Aerobic dive limits in immature Weddell seals. J Comp Physiol 151: 171–174, 1983.
 115. Kooyman GL, Cornell LH. Flow properties of expiration and inspiration in a trained bottlenose porpoise. Physiol Zool 54: 55–61, 1981.
 116. Kooyman GL, Hammond DD, Schroeder JP. Bronchograms and tracheograms of seals under pressure. Science 169: 82–84, 1970.
 117. Kooyman GL, Kerem DH, Campbell WB, Wright JJ. Pulmonary function in freely diving Weddell seals, Leptonychotes weddellii. Respir Physiol 12: 271–282, 1971.
 118. Kooyman GL, Kerem DH, Campbell WB, Wright JJ. Pulmonary gas exchange in freely diving Weddell seals (Leptonychotes weddellii). Respir Physiol 17: 283–290, 1973.
 119. Kooyman GL, Norris KS, Gentry RL. Spout of the gray whale: Its physical characteristics. Science 190: 908–910, 1975.
 120. Kooyman GL, Ponganis PJ. The physiological basis of diving to depth: Birds and mammals. Annu Rev Physiol 60: 19–32, 1998.
 121. Kooyman GL, Ponganis PJ, Howard RS. Diving animals. In: Lundgren C, Miller J, editors. The Lung at Depth. New York: Marcel Dekker, 1999, p. 686.
 122. Kooyman GL, Schroeder JP, Denison DM, Hammond DD, Wright JJ, Bergman WD. Blood N2 tensions of seals during simulated deep dives. Am J Physiol 223: 1016–1020, 1973.
 123. Kooyman GL, Sinnett EE. Mechanical properties of the harbor porpoise lung. Respir Physiol 36: 287–300, 1979.
 124. Kooyman GL, Sinnett EE. Pulmonary shunts in harbor seals and sea lions during simulated dives to depth. Physiol Zool 55: 105–111, 1982.
 125. Kooyman GL, Wahrenbrock EA, Castellini MA, Davis RW, Sinnett EE. Aerobic and anaerobic metabolism during voluntary diving in Weddell seals: Evidence of preferred pathways from blood chemistry and behavior. J Comp Physiol 138: 335–346, 1980.
 126. Kramer DL. The behavioral ecology of air breathing by aquatic mammals. Can J Zool 66: 89–94, 1988.
 127. Kvietys PR, Granger DN. Relation between intestinal blood flow and oxygen uptake. Am J Physiol 242: G202–G208, 1982.
 128. Le Boeuf BJ, Costa DP, Huntley AC, Feldkamp SD. Continuous, deep diving in female Northern seals, Mirounga angustirostris. Can J Zool 66: 446–458, 1988.
 129. Leith D. Comparative mammalian respiratory mechanics. Physiologist 19: 485–510, 1976.
 130. Leith D, Lowe R, Gillespie J. Mechanics of baleen whale lungs. Fed Proc 31: 335, 1972.
 131. Leith DE. Adaptations to deep breath‐hold diving: Respiratory and circulatory mechanics. Undersea Biomed Res 16: 345–353, 1989.
 132. Lenfant C. Physiological properties of blood of marine mammals. In: Anderson HT, editor. The Biology of Marine Mammals. New York: Academic Press, 1969, p. 95–116.
 133. Lenfant C, Johansen K, Torrance JD. Gas transport and oxygen storage capacity in some pinnipeds and the sea otter. Respir Physiol 9: 277–286, 1970.
 134. Liggins GC, Qvist J, Hochachka PW, Murphy BJ, Creasy RK, Schneider RC, Snider MT, Zapol WM. Fetal cardiovascular and metabolic responses to simulated diving the Weddell seal. J Appl Physiol 49: 424–430, 1980.
 135. Lindholm P, Ekborn A, Oberg D, Gennser M. Pulmonary edema and hemoptypsis after breath‐hold diving at residual volume. J Appl Physiol 102: 912–917, 2008.
 136. Liner MH, Andersson JPA. Pulmonary edema after competitive breath‐hold diving. J Appl Physiol 102: 986–990, 2008.
 137. Lockyer C. Body weights of some species of large whales. J Cons Int Explor Mer 36: 259–273, 1976.
 138. Lutz J, Henrich H, Bauereisen E. Oxygen supply and uptake in the liver and the intestine. Pflugers Arch 360: 7–15, 1975.
 139. Marsh H, Spain AV, Heinsohn GE. Physiology of the dugong. Comp Biochem Physiol A 61: 159–168, 1978.
 140. Mate BR, Rossbach KA, Nieukirk SL, Wells RS, Irvine AB, Scott MD, Read AJ. Satellite‐monitored movements and dive behavior of a bottlenose dolphin (Tursiops truncatus) in Tampa Bay, Florida. Mar Mamm Sci 11: 452–463, 1995.
 141. McFarland WL, Jacobs MS, Morgane PJ. Blood supply to the brain of the dolphin, Tursiops truncatus, with comparative observations on special aspects of the cerebrovascular supply of other vertebrates. Neurosci Biobehav Rev 3: 193, 1979.
 142. Meir JU, Champagne CD, Costa DP, Williams CL, Ponganis PJ. Extreme hypoxemic tolerance and blood oxygen depletion in diving elephant seals. Meir JU, Champagne C, Costa DP, Williams CL, Ponganis PJ. Extreme hypoxemic tolerance and blood oxygen depletion in diving elephant seals. Am J Physiol Regul Integr Comp Physiol 297: R927–939, 2009.
 143. Merrick RL, Loughlin TR. Foraging behavior of adult female and young‐of‐the‐year Steller sea lions in Alaskan waters. Can J Zool 75: 776–786, 1997.
 144. Miller NJ, Daniels CB, Costa DP, Orgeig S. Control of surfactant secretion in adult California sea lions. Biochem Biophys Res Commun 313: 727–732, 2004.
 145. Miller NJ, Daniels CB, Schurch S, Schoel WM, Orgeig S. The surface activity of pulmonary surfactant from diving mammals. Respir Physiol Neurobiol 150: 220–232, 2006.
 146. Miller NJ, Postle AD, Orgeig S, Coster G, Daniels CB. The composition of pulmonary surfactant from diving mammals. Respir Physiol Neurobiol 152: 152–168, 2006.
 147. Miller NJ, Postle AD, Scurch S, Schoel WM, Daniels CB, Orgeig S. The development of the pulmonary surfactant system in California sea lions. Comp Biochem Physiol A 141: 191–199, 2005.
 148. Miller PJ, Johnson MP, Tyack PL, Terray EA. Swimming gait, passive drag and buoyancy of diving sperm whales. J Exp Biol 207: 1953–1967, 2004.
 149. Molyneux GS, Bryden MM. Arteriovenous anastomoses in the skin of the Weddell seal (Leptonychotes weddellii). Science 189: 1100–1102, 1975.
 150. Molyneux GS, Bryden MM. Arteriovenous anastomoses in the skin of seals I. the Weddell seal (Leptonychotes weddellii) and the elephant seal (Mirounga leonina) (Pinnipedia: Phocidae). Anat Rec 191: 239–252, 1978.
 151. Moore MJ, Bogomolni AL, Dennison SE, Early G, Garner MM, Hayward BA, Lentell BJ, Rotstein DS. Gas bubbles in seals, dolphins, and porpoises entangled and drowned at depth in gillnets. Vet Pathol 46: 536–547, 2009.
 152. Moore MJ, Early GA. Cumulative sperm whale bone damage and the bends. Science 306: 2215, 2004.
 153. Nawojchik R, St. Aubin DJ, Johnson A. Movements and dive behavior of two stranded, rehabilitated long‐finned pilot whales (Globicephala melas) in the Northwest Atlantic. Mar Mamm Sci 19: 232–239, 2003.
 154. Neshumova TV, Cherepanova VA. Blood supply and myoglobin stocks in muscles of the seal Pusa siberica and muskrat Ondatra zibethica. J Evol Biochem Physiol 20: 282–287, 1984.
 155. Nichols JW, Weber LJ. Comparative oxygen affinity of fish and mammalian myoglobins. J Comp Physiol B 159: 205–210, 1989.
 156. Ninomiya H, Inomata T, Shirouzu H, Katsumata E. Microanatomy of the terminal air spaces of Baird's beaked whale (Berardius bairdii) lungs. J Vet Med Sci 67: 473–479, 2005.
 157. Noren SR, Williams TM. Body size and skeletal muscle myoglobin of cetaceans: Adaptations for maximizing dive duration. Comp Biochem Physiol A 126: 181–191, 2000.
 158. Norris KS, Harvey GW. A theory of the function of the spermaceti organ of the sperm whale (Physeter catodon L.). In: Galler SF, Schmidt‐Koenig K, Jacobs GJ, Belleville RE, editors. Animal Orientation and Navigation. Washington, DC: NASA, 1972, p. 397–417.
 159. Nowicki SN, Stirling I, Sjare B. Duration of stereotyped underwater vocal displays by male Atlantic walruses in relation to aerobic dive limit. Mar Mamm Sci 13: 566–575, 1997.
 160. Nunn JF. Applied Respiratory Physiology. London: Butterworths, 1977, p. 524.
 161. Odden A, Folkow LP, Caputa M, Hotvedt R, Blix AS. Brain cooling in seals. Acta Physiol Scand 166: 77–78, 1999.
 162. Odend'hal S, Poulter TC. Pressure regulation in the middle ear cavity of sea lions: A possible mechanism. Science 153: 768–769, 1966.
 163. Olsen CR, Elsner R, Hale FC, Kenney DW. “Blow” of the pilot whale. Science 163: 953–955, 1969.
 164. Olsen CR, Hale FC, Elsner R. Mechanics of ventilation in the pilot whale. Respir Physiol 7: 137–149, 1969.
 165. Ordway GA, Garry DJ. Myoglobin: An essential hemoprotein in striated muscle. J Exp Biol 207: 3441–3446, 2004.
 166. Papastavrou V, Smith SC, Whitehead H. Diving behaviour of the sperm whale, Physeter macrocephalus, off the Galapagos Islands. Can J Zool 67: 839–846, 1989.
 167. Paulev P. Decompression sickness following repeated breath‐hold dives. J Appl Physiol 20: 1028–1031, 1965.
 168. Petrov EA, Shoshenko KA. Total store of oxygen and duration of diving of the Nerpa. In: Galazii GI, editor. Morphology and Ecology of Fish. Novbosibirsk: Academy of Sciences of Russia, Siberian Division, 1987, p. 110–128.
 169. Piscitelli M, McLellan W, Rommel S, Blum J, Barco S, Pabst DA. Lung size and thoracic morphology in shallow (Tursiops truncatus) and deep (Kogia spp.) diving cetaceans. J Morph Lung size and thoracic morphology in shallow (Tursiops truncatus) and deep (Kogia spp.) diving cetaceans. J Morphol 271: 654–673, 2010.
 170. Polasek L, Davis RW. Heterogeneity of myoglobin distribution in the locomotory muscles of five cetacean species. J Exp Biol 204: 209–215, 2001.
 171. Polasek L, Dickson KA, Davis RW. Metabolic indicators in the skeletal muscles of harbor seals (Phoca vitulina). Am J Physiol 290: R1720–R1727, 2006.
 172. Ponganis PJ, Kooyman GL, Baronov EA, Thorson PH, Stewart BS. The aerobic submersion limit of Baikal seals, Phoca sibirica. Can J Zool 75: 1323–1327, 1997.
 173. Ponganis PJ, Kooyman GL, Castellini MA. Determinants of the aerobic dive limit of Weddell seals: Analysis of diving metabolic rates, post‐dive end tidal Po2's, and blood and muscle oxygen stores. Physiol Zool 66: 732–749, 1993.
 174. Ponganis PJ, Kooyman GL, Ridgway SH. Comparative diving physiology. In: Brubakk AO, Neuman TS, editors. Physiology and Medicine of Diving. Edinburgh, UK: Saunders, 2003, p. 779.
 175. Ponganis PJ, Kooyman GL, Winter LM, Starke LN. Heart rate and plasma lactate responses during submerged swimming and diving in California sea lions (Zalophus californianus). J Comp Physiol B 167: 9–16, 1997.
 176. Ponganis PJ, Kooyman GL, Zornow MH. Cardiac output in swimming California sea lions, Zalophus californianus. Physiol Zool 64: 1296–1306, 1991.
 177. Ponganis PJ, Kooyman GL, Zornow MH, Castellini MA, Croll DA. Cardiac output and stroke volume in swimming harbor seals. J Comp Physiol 160B: 473–482, 1990.
 178. Ponganis PJ, Kreutzer U, Stockard TK, Lin PC, Sailasuta N, Tran T‐K, Hurd R, Jue T. Blood flow and metabolic regulation in seal muscle during apnea. J Exp Biol 211: 3323–3332, 2008.
 179. Ponganis PJ, Pierce RW. Muscle metabolic profiles and fiber‐type composition in some marine mammals. Comp Biochem Physiol B 59: 99–102, 1978.
 180. Ponganis PJ, Stockard T, Levenson DH, Berg L, Barnov EA. Cardiac output and muscle blood flow during rest‐associated apneas in elephant seals. Comp Biochem Physiol A 144: 105–111, 2006.
 181. Qvist J, Hill RD, Schneider RC, Falke KJ, Liggins GC, Guppy M, Elliott RL, Hochachka PW, Zapol WM. Hemoglobin concentrations and blood gas tensions of free‐diving Weddell seals. J Appl Physiol 61: 1560–1569, 1986.
 182. Qvist J, Hurford WE, Park YS, Radermacher P, Falke KJ, Ahn DW, Guyton GP, Stanek KS, Hong SK, Weber RE, Zapol WM. Arterial blood gas tensions during breath‐hold diving in the Korean ama. J Appl Physiol 75: 285–293, 1993.
 183. Qvist J, Weber RE, Zapol WM. Oxygen equilibrium properties of blood and hemoglobin of fetal and adult Weddell seals. J Appl Physiol 50: 999–1005, 1981.
 184. Ralls K, Hatfield BB, Siniff DB. Foraging patterns of California sea otters as indicated by telemetry. Can J Zool 73: 523–531, 1995.
 185. Ramirez J‐M, Folkow LP, Blix AS. Hypoxia tolerance in mammals and birds: From the wilderness to the clinic. Annu Rev Physiol 69: 113–143, 2007.
 186. Reed JZ, Butler PJ, Fedak MA. The metabolic characteristics of the locomotory muscles of grey seals (Halichoerus grypus), harbour seals (Phoca vitulina), and Antarctic fur seals (Arctocephalus gazella). J Exp Biol 194: 33–46, 1994.
 187. Reed JZ, Chambers C, Fedak MA, Butler PJ. Gas exchange of captive freely diving grey seals (Halichoerus grypus). J Exp Biol 191: 1–18, 1994.
 188. Reed JZ, Chambers C, Hunter CJ, Lockyer C, Kastelein R, Fedak MA, Boutilier RG. Gas exchange and heart rate in the harbour porpoise, Phocoena phocoena. J Comp Physiol B 170: 1–10, 2000.
 189. Reynolds JE III. Behavior patterns in the West Indian manatee, with emphasis of feeding and diving (Florida). Science 44: 232–242, 1981.
 190. Reynolds JE III, Odell DK. Manatees and Dugongs. New York: Facts on File Inc., 1991, p. 192.
 191. Richmond JP, Burns JM, Rea LD. Ontogeny of total body oxygen stores and aerobic dive potential in the Steller sea lion (Eumetopias jubatus). J Comp Physiol B 176: 535–545, 2006.
 192. Ridgway SH. Diving by cetaceans. In: Brubakk AO, Kanwisher JW, Sundnes G, editors. Diving in Animals and Man. Trondheim: Royal Norwegian Society of Science and Letters, 1986, p. 33–62.
 193. Ridgway SH, Howard R. Dolphin lung collapse and intramuscular circulation during free diving: Evidence from nitrogen washout. Science 206: 1182–1183, 1979.
 194. Ridgway SH, Johnston DG. Blood oxygen and ecology of porpoises of three genera. Science 151: 456–458, 1966.
 195. Ridgway SH, Scronce BL, Kanwisher J. Respiration and deep diving in the bottlenose porpoise. Science 166: 1651–1654, 1969.
 196. Roca J, Agusti AGN, Alonso A, Poole DC, Viegas C, Barbera JA, Rodriguez‐Roisin R, Ferrer A, Wagner PD. Effects of training on muscle O2 transport at Vo2MAX. J Appl Physiol 73: 1067–1076, 1992.
 197. Schaeffer KE, Allison RD, Dougherty JH Jr, Carey CR, Walker R, Yost F, Parker D. Pulmonary and circulatory adjustments determining the limits of depths in breathhold diving. Science 162: 1020–1023, 1968.
 198. Schenkman KA, Marble DA, Burns DH, Feigl EO. Myoglobin oxygen dissociation by multiwavelength spectroscopy. J Appl Physiol 82: 86–92, 1997.
 199. Scholander PF. Experimental investigations on the respiratory function in diving mammals and birds. Hvalradets skrifter 22: 1–131, 1940.
 200. Scholander PF, Irving L. Experimental investigations on the respiration and diving of the Florida manatee. J Cell Comp Physiol 17: 169–191, 1941.
 201. Scholander PF, Irving L, Grinnell SW. Aerobic and anaerobic changes in seal muscle during diving. J Biol Chem 142: 431–440, 1942.
 202. Scholander PF, Schevill WE. Counter‐current vascular heat exchange in the fins of whales. J Appl Physiol 8: 279–282, 1955.
 203. Schreer JF, Testa JW. Classification of Weddell seal diving behavior. Mar Mamm Sci 12: 227–250, 1996.
 204. Scott MS, Chivers SJ. Movements and diving behavior of pelagic spotted dolphins. Mar Mamm Sci 25: 137–160, 2009.
 205. Shaffer SA, Costa DP, Williams TM, Ridgway SH. Diving and swimming performance of white whales, Delphinapterus leucas: An assessment of plasma lactate and blood gas levels and respiratory rates. J Exp Biol 200: 3091–3099, 1997.
 206. Simon L, Robin E, Elsner R, Van Kessel A, Theodore J. A biochemical basis for differences in maximal diving time in aquatic mammals. Comp Biochem Physiol B 47: 209–215, 1974.
 207. Simpson JG, Gilmartin WG, Ridgway SH. Blood volume and other hematologic values in young elephant seals (Mirounga angustirostris). Am J Vet Res 31: 14449–11452, 1970.
 208. Skrovan RC, Williams TM, Berry PS, Moore PW, Davis RW. The diving physiology of bottlenose dolphins (Tursiops truncatus), part II: Biomechanics and changes in buoyancy at depth. J Exp Biol 202: 2749–2761, 1999.
 209. Sleet RB, Sumich JL, Weber LJ. Estimates of total blood volume and total body weight of sperm whale (Physeter catodon). Can J Zool 59: 567–570, 1981.
 210. Slijper EJ. Whales. London: Hutchinson & Co., 1962, p. 475.
 211. Soto NA, Johnson MP, Madsen PT, Diaz F, Dominguez I, Brito A, Tyack P. Cheetahs of the deep sea: Deep foraging sprints in short‐finned pilot whales off Tenerife (Canary Islands). J Anim Ecol 77: 936–947, 2008.
 212. Sparling CE, Fedak MA, Thompson D. Eat now, pay later? Evidence of deferred food processing costs in diving seals. Biol Lett 3: 94–98, 2007.
 213. Spragg R, Ponganis PJ, Marsh JJ, Rau GA, Bernhard W. Surfactant from diving aquatic mammals. J Appl Physiol 96: 1626–1632, 2004.
 214. Stewart BS, DeLong RL. Double migrations of the northern elephant seal, Mirounga angustirostris. J Mammal 76: 196–205, 1995.
 215. Stirling I. Midsummer observations on behavior of wild polar bears (Ursus maritimus). Can J Zool 52: 1191–1198, 1974.
 216. Stockard TK, Levenson DH, Berg L, Fransioli JR, Baranov EA, Ponganis PJ. Blood oxygen depletion during rest‐associated apneas of northern elephant seals (Mirounga angustirostris). J Exp Biol 210: 2607–2617, 2007.
 217. Storey K, Hochachka PW. Glycolytic enzymes in muscle of the Pacific dolphin: Role of pyruvate kinase in aerobic‐anaerobic transitions during diving. Comp Biochem Physiol B 49: 119–128, 1974.
 218. Suzuki T, Imai K. Evolution of myoglobin. Cell Mol Life Sci 54: 979–1004, 1998.
 219. Tarasoff FJ, Kooyman GL. Observations on the anatomy of the respiratory system of the river otter, sea otter, and harp seal, part II: The trachea and bronchial tree. Can J Zool 51: 171–177, 1973.
 220. Tawara T. On the respiratory pigments of whale: Studies on whale blood, part II. Sci Rep Whales Res Inst 3: 95–101, 1950.
 221. Taylor CR, Karas RH, Weibel ER, Hoppeler H. Adaptive variation in the mammalian respiratory system in relation to energetic demand, part II: Reaching the limits to oxygen flow. Respir Physiol 69: 7–26, 1987.
 222. Thompson D, Fedak MA. Cardiac responses of grey seals during diving at sea. J Exp Biol 174: 139–164, 1993.
 223. Thorson PH, Le Boeuf BJ. Developmental aspects of diving in northern elephant seal pups. In: Le Boeuf BJ, Laws RM, editors. Elephant Seals: Population Ecology, Behavior, and Physiology. Berkeley: University of California Press, 1994, p. 271–289.
 224. Torday HS, Rehan VK. Stretch‐induced surfactant synthesis is coordinated by the paracrine actions of PTHrP and leptin. Am J Physiol 283: L130–L135, 2002.
 225. Tyack PL, Johnson M, Aguilar Soto N, Sturlese A, Madsen PT. Extreme diving of beaked whales. J Exp Biol 209: 4238–4253, 2006.
 226. Valtin H. Renal Function: Mechanisms Preserving Fluid and Solute Balance in Health. Boston, MA: Little Brown & Co, 1973.
 227. VanCitters RL, Smith OA, Watson NW, Franklin DL. Field study of diving responses in the northern elephant seal. Hvalradets skrifter 48: 15–23, 1965.
 228. van Nie CJ, Van Der Kamp JS. The closure of the foramen ovale and the ductus arteriosus in the common seal (Phoca vitulina, L. 1758). A morphological approach. Aquat Mamm 14: 82–85, 1988.
 229. Vogl AW, Fisher HD. Arterial retia related to supply of the central nervous system in two small toothed whales—Narwhal (Monodon monoceros) and Beluga (Delphinapterus leucas). J Morphol 174: 41–56, 1982.
 230. Watkins WA, Daher MA, Fristrup KM, Howald TJ, Notarbartolo di Sciara G. Sperm whales tagged with transponders and tracked underwater by sonar. Mar Mamm Sci 9: 55–67, 1993.
 231. Watson RR, Miller TA, Davis RW. Immunohistochemical fiber typing of harbor seal skeletal muscle. J Exp Biol 206: 4105–4111, 2003.
 232. Watwood SL, Miller PJO, Johnson M, Madsen PT, Tyack PL. Deep‐diving foraging behaviour of sperm whales (Physeter macrocephalus). J Anim Ecol 75: 814–825, 2006.
 233. Webb PM, Andrews RD, Costa DP, Le Boeuf BJ. Heart rate and oxygen consumption of northern elephant seals during diving in the laboratory. Physiol Zool 71: 116–125, 1998.
 234. Weise MJ, Costa DP. Total body oxygen stores and physiological diving capacity of California sea lions as a function of sex and age. J Exp Biol 210: 278–289, 2007.
 235. Welsch U, Riedel‐Sheimer B. Histophysiological observations on the external auditory meatus, middle, and inner of the Weddell seal (Leptonychotes weddellii). J Morphol 234: 25–36, 1997.
 236. West JB. Pulmonary Physiology and Pathophysiology. Philadelphia: Lippincott Williams & Wilkins, 2007, p. 150.
 237. Westgate AJ, Reas AJ, Berggren P, Koopman HN, Gaskin DE. Diving behavior of harbour porpoises, Phocoena phocoena. Can J Fish Aquat Sci 52: 1064–1073, 1995.
 238. White JR, Harkness DR, Isaacks RE, Duffield DA. Some studies on blood of the Florida manatee, Trichechus manutus latirostris. Comp Biochem Physiol A 55: 413–417, 1976.
 239. Wiig O, Gjertz I, Griffith D, Lydersen C. Diving patterns of an Atlantic walrus Odobenus rosmarus rosmarus near Svalbard. Polar Biol 13: 71–72, 1993.
 240. Williams TM, Davis RW, Fuiman LA, Francis J, Le Boeuf BJ, Horning M, Calambokidis J, Croll DA. Sink or swim: Strategies for cost‐efficient diving by marine mammals. Science 288: 133–136, 2000.
 241. Williams TM, Friedl WA, Fong ML, Yamada RM, Sedivy P, Haun JE. Travel at low energetic cost by swimming and wave‐riding bottlenose dolphins. Nature 355: 821–823, 1992.
 242. Williams TM, Friedl WA, Haun JE. The physiology of bottlenose dolphins (Tursiops truncatus): Heart rate, metabolic rate and plasma lactate concentration during exercise. J Exp Biol 179: 31–46, 1993.
 243. Williams TM, Fuiman LA, Horning M, Davis RW. The cost of foraging by a marine predator, the Weddell seal Leptonychotes weddellii: pricing by the stroke. J Exp Biol 207: 973–982, 2004.
 244. Williams TM, Haun JE, Friedl WA. The diving physiology of bottlenose dolphins (Tursiops truncatus), part I: Balancing the demands of exercise for energy conservation at depth. J Exp Biol 202: 2739–2748, 1999.
 245. Williams TM, Kooyman GL, Croll DA. The effects of submergence on heart rate and oxygen consumption of swimming seals and sea lions. J Comp Physiol B 160: 637–644, 1991.
 246. Williams TM, Zavanelli M, Miller MA, Goldbeck RA, Morledge M, Casper D, Pabst DA, McClellan W, Cantin LP, Kliger DS. Running, swimming, and diving modifies neuroprotecting globins in the mammalian brain. Proc R Soc London B Biol Sci 275: 751–758, 2008.
 247. Witteveen BH, Foy RJ, Wynne KM, Tremblay Y. Investigation of foraging habits and prey selection by humpback whales (Megaptera novaeangliae) using acoustic tags and concurrent fish surveys. Mar Mamm Sci 24: 516–534, 2008.
 248. Yeates LC, Williams TM, Fink TL. Diving and foraging energetics of the smallest marine mammal, the sea otter (Enhydra lutris). J Exp Biol 210: 1960–1970, 2007.
 249. Zapol WM, Liggins GC, Schneider RC, Qvist J, Snider MT, Creasy RK, Hochachka PW. Regional blood flow during simulated diving in the conscious Weddell seal. J Appl Physiol 47: 968–973, 1979.
 250. Zimmer WMX, Tyack PL. Repetitive shallow dives pose decompression risk in deep‐diving beaked whales. Mar Mamm Sci 23: 888–925, 2007.

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Paul J. Ponganis. Diving Mammals. Compr Physiol 2011, 1: 447-465. doi: 10.1002/cphy.c091003