Thermoregulation in the northern elephant seal, Mirounga angustirostris

Field Physiology: Studying Organismal Function in the Natural Environment

“…A key focus of temperature measurement in free-ranging animals has been to track core temperature values and fluctuations as they occur in the wild (Figure 7A). Body temperature measurements have been collected in a wide range of taxa, including sharks (46,213); toads (275); alligators (282); crocodiles (274,276); sea turtles (264,290); boas (296); bats (291); tits (255); penguins (36,60,124,125,243,244); muskrats (179); ground squirrels (326); pika (181); moose (305); wildebeest (148); springbok (206); ostrich (92); seals (131,196,199); and vervet monkeys (175). Most commonly, this has been accomplished by implanting a temperature measurement device into the peritoneal cavity; however, other successful approaches have included a vaginal implant (305), tympanic membrane temperature (120), and arterial blood temperature (131,148,199).…”

Field Physiology: Studying Organismal Function in the Natural Environment

“…A key focus of temperature measurement in free-ranging animals has been to track core temperature values and fluctuations as they occur in the wild (Figure 7A). Body temperature measurements have been collected in a wide range of taxa, including sharks (46,213); toads (275); alligators (282); crocodiles (274,276); sea turtles (264,290); boas (296); bats (291); tits (255); penguins (36,60,124,125,243,244); muskrats (179); ground squirrels (326); pika (181); moose (305); wildebeest (148); springbok (206); ostrich (92); seals (131,196,199); and vervet monkeys (175). Most commonly, this has been accomplished by implanting a temperature measurement device into the peritoneal cavity; however, other successful approaches have included a vaginal implant (305), tympanic membrane temperature (120), and arterial blood temperature (131,148,199).…”

Registros nuevos de pinnípedos no-residentes en el golfo de California, México

“…Also contrary to this idea is the fact that the average air temperatures on the beaches with the best characteristics for breeding (i.e. Granito and Ángel de la Guarda islands), are 5° C warmer than the average in the San Benito archipelago during winter, which together with Isla Natividad are the northern elephant seal's warmest breeding grounds in the Pacifi c. Although winter water temperatures are similar in both areas, the higher air temperatures would mean a higher energetic cost due to thermoregulatory stress while on the beach on warmer days (McGinnis and Southworth, 1971). Finally, the long distance and time to reach traditional feeding areas of both males and females in the Gulf of Alaska (Le Boeuf and Crocker, 2005), the delay in trip days (shortening the breeding season), and the high energetic cost of such a trip (approximately 4 000 km or more, multiplied by 2 annual round trips) would not allow the establishment of a reproductive colony in the Gulf of California.…”

Stroke volume and cardiac output in juvenile elephant seals during forced dives

“…During such experimental protocols, restraining devices may further restrict cutaneous heat loss from the animal. Temperature regulation in phocids is accomplished primarily through peripheral vasoregulation (McGinnis et al, 1971), therefore a decrease in total peripheral resistance due to heat dissipation may have resulted in a higher diving heart rate (Q=mean arterial blood pressure/total peripheral resistance). However, experiments on harbor seals (Hammel et al, 1977) showed that diving-induced peripheral vasoconstriction overrides the increased cutaneous blood flow normally elicited in the presence of a thermal load but results in an increase in flipper vasodilation, as indicated by a 10°C rise in flipper temperature.…”

Field Physiology: Studying Organismal Function in the Natural Environment

“…A key focus of temperature measurement in free-ranging animals has been to track core temperature values and fluctuations as they occur in the wild (Figure 7A). Body temperature measurements have been collected in a wide range of taxa, including sharks (46,213); toads (275); alligators (282); crocodiles (274,276); sea turtles (264,290); boas (296); bats (291); tits (255); penguins (36,60,124,125,243,244); muskrats (179); ground squirrels (326); pika (181); moose (305); wildebeest (148); springbok (206); ostrich (92); seals (131,196,199); and vervet monkeys (175). Most commonly, this has been accomplished by implanting a temperature measurement device into the peritoneal cavity; however, other successful approaches have included a vaginal implant (305), tympanic membrane temperature (120), and arterial blood temperature (131,148,199).…”

Registros nuevos de pinnípedos no-residentes en el golfo de California, México

“…Also contrary to this idea is the fact that the average air temperatures on the beaches with the best characteristics for breeding (i.e. Granito and Ángel de la Guarda islands), are 5° C warmer than the average in the San Benito archipelago during winter, which together with Isla Natividad are the northern elephant seal's warmest breeding grounds in the Pacifi c. Although winter water temperatures are similar in both areas, the higher air temperatures would mean a higher energetic cost due to thermoregulatory stress while on the beach on warmer days (McGinnis and Southworth, 1971). Finally, the long distance and time to reach traditional feeding areas of both males and females in the Gulf of Alaska (Le Boeuf and Crocker, 2005), the delay in trip days (shortening the breeding season), and the high energetic cost of such a trip (approximately 4 000 km or more, multiplied by 2 annual round trips) would not allow the establishment of a reproductive colony in the Gulf of California.…”

Stroke volume and cardiac output in juvenile elephant seals during forced dives

“…During such experimental protocols, restraining devices may further restrict cutaneous heat loss from the animal. Temperature regulation in phocids is accomplished primarily through peripheral vasoregulation (McGinnis et al, 1971), therefore a decrease in total peripheral resistance due to heat dissipation may have resulted in a higher diving heart rate (Q=mean arterial blood pressure/total peripheral resistance). However, experiments on harbor seals (Hammel et al, 1977) showed that diving-induced peripheral vasoconstriction overrides the increased cutaneous blood flow normally elicited in the presence of a thermal load but results in an increase in flipper vasodilation, as indicated by a 10°C rise in flipper temperature.…”

Field Physiology: Studying Organismal Function in the Natural Environment

“…A key focus of temperature measurement in free-ranging animals has been to track core temperature values and fluctuations as they occur in the wild (Figure 7A). Body temperature measurements have been collected in a wide range of taxa, including sharks (46,213); toads (275); alligators (282); crocodiles (274,276); sea turtles (264,290); boas (296); bats (291); tits (255); penguins (36,60,124,125,243,244); muskrats (179); ground squirrels (326); pika (181); moose (305); wildebeest (148); springbok (206); ostrich (92); seals (131,196,199); and vervet monkeys (175). Most commonly, this has been accomplished by implanting a temperature measurement device into the peritoneal cavity; however, other successful approaches have included a vaginal implant (305), tympanic membrane temperature (120), and arterial blood temperature (131,148,199).…”

Registros nuevos de pinnípedos no-residentes en el golfo de California, México

“…Also contrary to this idea is the fact that the average air temperatures on the beaches with the best characteristics for breeding (i.e. Granito and Ángel de la Guarda islands), are 5° C warmer than the average in the San Benito archipelago during winter, which together with Isla Natividad are the northern elephant seal's warmest breeding grounds in the Pacifi c. Although winter water temperatures are similar in both areas, the higher air temperatures would mean a higher energetic cost due to thermoregulatory stress while on the beach on warmer days (McGinnis and Southworth, 1971). Finally, the long distance and time to reach traditional feeding areas of both males and females in the Gulf of Alaska (Le Boeuf and Crocker, 2005), the delay in trip days (shortening the breeding season), and the high energetic cost of such a trip (approximately 4 000 km or more, multiplied by 2 annual round trips) would not allow the establishment of a reproductive colony in the Gulf of California.…”

Stroke volume and cardiac output in juvenile elephant seals during forced dives

“…During such experimental protocols, restraining devices may further restrict cutaneous heat loss from the animal. Temperature regulation in phocids is accomplished primarily through peripheral vasoregulation (McGinnis et al, 1971), therefore a decrease in total peripheral resistance due to heat dissipation may have resulted in a higher diving heart rate (Q=mean arterial blood pressure/total peripheral resistance). However, experiments on harbor seals (Hammel et al, 1977) showed that diving-induced peripheral vasoconstriction overrides the increased cutaneous blood flow normally elicited in the presence of a thermal load but results in an increase in flipper vasodilation, as indicated by a 10°C rise in flipper temperature.…”