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Gusztak RW, MacArthur RA, Campbell KL. Dive performance and aquatic thermoregulation of the world’s smallest mammalian diver, the American water shrew (Sorex palustris). Physiol Biochem Zool 2022; 95:438-463. [DOI: 10.1086/721186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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2
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Enstipp MR, Bost CA, Le Bohec C, Chatelain N, Weimerskirch H, Handrich Y. The early life of king penguins: ontogeny of dive capacity and foraging behaviour in an expert diver. J Exp Biol 2021; 224:269166. [PMID: 34132335 DOI: 10.1242/jeb.242512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/24/2021] [Indexed: 11/20/2022]
Abstract
The period of emancipation in seabirds, when juveniles change from a terrestrial existence to a life at sea, is associated with many challenges. Apart from finding favourable foraging sites, they have to develop effective prey search patterns and physiological capacities that enable them to capture sufficient prey to meet their energetic needs. Animals that dive to forage, such as king penguins (Aptenodytes patagonicus), need to acquire an adequate breath-hold capacity, allowing them to locate and capture prey at depth. To investigate the ontogeny of their dive capacity and foraging performance, we implanted juvenile king penguins before their first departure to sea and also adult breeders with a data-logger recording pressure and temperature. We found that juvenile king penguins possess a remarkable dive capacity when leaving their natal colony, enabling them to conduct dives in excess of 100 m within their first week at sea. Despite this, juvenile dive/foraging performance, investigated in relation to dive depth, remained below the adult level throughout their first year at sea, probably reflecting physiological limitations as a result of incomplete maturation. A significantly shallower foraging depth of juveniles, particularly during their first 5 months at sea, could also indicate differences in foraging strategy and targeted prey. The initially greater wiggle rate suggests that juveniles fed opportunistically and also targeted different prey from adults and/or that many of the wiggles of juveniles reflect unsuccessful prey-capture attempts, indicating a lower foraging proficiency. After 5 months, this difference disappeared, suggesting sufficient physical maturation and improvement of juvenile foraging skills.
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Affiliation(s)
- Manfred R Enstipp
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France.,Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Charles-André Bost
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Céline Le Bohec
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France.,Centre Scientifique de Monaco, Département de Biologie Polaire, MC 98000, Monaco
| | - Nicolas Chatelain
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Henri Weimerskirch
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Yves Handrich
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
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3
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Beltran RS, Kilpatrick AM, Breed GA, Adachi T, Takahashi A, Naito Y, Robinson PW, Smith WO, Kirkham AL, Burns JM. Seasonal resource pulses and the foraging depth of a Southern Ocean top predator. Proc Biol Sci 2021; 288:20202817. [PMID: 33726591 PMCID: PMC8059541 DOI: 10.1098/rspb.2020.2817] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Seasonal resource pulses can have enormous impacts on species interactions. In marine ecosystems, air-breathing predators often drive their prey to deeper waters. However, it is unclear how ephemeral resource pulses such as near-surface phytoplankton blooms alter the vertical trade-off between predation avoidance and resource availability in consumers, and how these changes cascade to the diving behaviour of top predators. We integrated data on Weddell seal diving behaviour, diet stable isotopes, feeding success and mass gain to examine shifts in vertical foraging throughout ice break-out and the resulting phytoplankton bloom each year. We also tested hypotheses about the likely location of phytoplankton bloom origination (advected or produced in situ where seals foraged) based on sea ice break-out phenology and advection rates from several locations within 150 km of the seal colony. In early summer, seals foraged at deeper depths resulting in lower feeding rates and mass gain. As sea ice extent decreased throughout the summer, seals foraged at shallower depths and benefited from more efficient energy intake. Changes in diving depth were not due to seasonal shifts in seal diets or horizontal space use and instead may reflect a change in the vertical distribution of prey. Correspondence between the timing of seal shallowing and the resource pulse was variable from year to year and could not be readily explained by our existing understanding of the ocean and ice dynamics. Phytoplankton advection occurred faster than ice break-out, and seal dive shallowing occurred substantially earlier than local break-out. While there remains much to be learned about the marine ecosystem, it appears that an increase in prey abundance and accessibility via shallower distributions during the resource pulse could synchronize life-history phenology across trophic levels in this high-latitude ecosystem.
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Affiliation(s)
- Roxanne S Beltran
- Department of Biology and Wildlife, University of Alaska Fairbanks, 2090 Koyukuk Drive, Fairbanks, AK 99775, USA.,Department of Biological Sciences, University of Alaska Anchorage, 3101 Science Circle, Anchorage, AK 99508, USA.,Department of Ecology and Evolutionary Biology, University of California Santa Cruz, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - A Marm Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Greg A Breed
- Institute of Arctic Biology, University of Alaska Fairbanks, P.O. Box 757000, Fairbanks, AK 99775, USA
| | - Taiki Adachi
- Department of Biological Sciences, University of Tokyo, 2-11-16 Yayoi, Bunkyō, Tokyo 113-0032, Japan
| | - Akinori Takahashi
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Yasuhiko Naito
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Patrick W Robinson
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Walker O Smith
- Virginia Institute of Marine Science, College of William and Mary, 1375 Greate Rd, Gloucester Point, VA 23062, USA.,Institute of Oceanography, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200240, People's Republic of China
| | - Amy L Kirkham
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 17101 Point Lena Loop Road, Juneau, AK 99801, USA
| | - Jennifer M Burns
- Department of Biological Sciences, University of Alaska Anchorage, 3101 Science Circle, Anchorage, AK 99508, USA.,Department of Biological Sciences, Texas Tech University, Box 43131 Lubbock, TX 79409, USA
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Roussel D, Le Coadic M, Rouanet JL, Duchamp C. Skeletal muscle metabolism in sea-acclimatized king penguins. I. Thermogenic mechanisms. J Exp Biol 2020; 223:jeb233668. [PMID: 32968000 DOI: 10.1242/jeb.233668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 09/10/2020] [Indexed: 12/25/2022]
Abstract
At fledging, king penguin juveniles undergo a major energetic challenge to overcome the intense and prolonged energy demands for thermoregulation and locomotion imposed by life in cold seas. Among other responses, sea acclimatization triggers fuel selection in skeletal muscle metabolism towards lipid oxidation in vitro, which is reflected by a drastic increase in lipid-induced thermogenesis in vivo However, the exact nature of skeletal muscle thermogenic mechanisms (shivering and/or non-shivering thermogenesis) remains undefined. The aim of the present study was to determine in vivo whether the capacity for non-shivering thermogenesis was enhanced by sea acclimatization. We measured body temperature, metabolic rate, heart rate and shivering activity in fully immersed king penguins (Aptenodytes patagonicus) exposed to water temperatures ranging from 12 to 29°C. Results from terrestrial pre-fledging juveniles were compared with those from sea-acclimatized immature penguins (hereafter 'immatures'). The capacity for thermogenesis in water was as effective in juveniles as in immatures, while the capacity for non-shivering thermogenesis was not reinforced by sea acclimatization. This result suggests that king penguins mainly rely on skeletal muscle contraction (shivering or locomotor activity) to maintain endothermy at sea. Sea-acclimatized immature penguins also exhibited higher shivering efficiency and oxygen pulse (amount of oxygen consumed or energy expended per heartbeat) than pre-fledging juvenile birds. Such increase in shivering and cardiovascular efficiency may favor a more efficient activity-thermoregulatory heat substitution providing penguins with the aptitude to survive the tremendous energetic challenge imposed by marine life in cold circumpolar oceans.
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Affiliation(s)
- Damien Roussel
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Marion Le Coadic
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Jean-Louis Rouanet
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Claude Duchamp
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
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Roussel D, Marmillot V, Monternier PA, Bourguignon A, Toullec G, Romestaing C, Duchamp C. Skeletal muscle metabolism in sea-acclimatized king penguins. II. Improved efficiency of mitochondrial bioenergetics. J Exp Biol 2020; 223:jeb233684. [PMID: 32967994 DOI: 10.1242/jeb.233684] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/10/2020] [Indexed: 08/25/2023]
Abstract
At fledging, juvenile king penguins (Aptenodytes patagonicus) must overcome the tremendous energetic constraints imposed by their marine habitat, including during sustained extensive swimming activity and deep dives in cold seawater. Both endurance swimming and skeletal muscle thermogenesis require high mitochondrial respiratory capacity while the submerged part of dive cycles repeatedly and greatly reduces oxygen availability, imposing a need for solutions to conserve oxygen. The aim of the present study was to determine in vitro whether skeletal muscle mitochondria become more 'thermogenic' to sustain heat production or more 'economical' to conserve oxygen in sea-acclimatized immature penguins (hereafter 'immatures') compared with terrestrial juveniles. Rates of mitochondrial oxidative phosphorylation were measured in permeabilized fibers and mitochondria from the pectoralis muscle. Mitochondrial ATP synthesis and coupling efficiency were measured in isolated muscle mitochondria. The mitochondrial activities of respiratory chain complexes and citrate synthase were also assessed. The results showed that respiration, ATP synthesis and respiratory chain complex activities in pectoralis muscles were increased by sea acclimatization. Furthermore, muscle mitochondria were on average 30-45% more energy efficient in sea-acclimatized immatures than in pre-fledging juveniles, depending on the respiratory substrate used (pyruvate, palmitoylcarnitine). Hence sea acclimatization favors the development of economical management of oxygen, decreasing the oxygen needed to produce a given amount of ATP. This mitochondrial phenotype may improve dive performance during the early marine life of king penguins, by extending their aerobic dive limit.
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Affiliation(s)
- Damien Roussel
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Vincent Marmillot
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Pierre-Axel Monternier
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Aurore Bourguignon
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Gaëlle Toullec
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Caroline Romestaing
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Claude Duchamp
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
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Enstipp MR, Bost CA, Le Bohec C, Bost C, Laesser R, Le Maho Y, Weimerskirch H, Handrich Y. The dive performance of immature king penguins following their annual molt suggests physiological constraints. J Exp Biol 2019; 222:222/20/jeb208900. [DOI: 10.1242/jeb.208900] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 09/17/2019] [Indexed: 11/20/2022]
Abstract
ABSTRACT
Like all birds, penguins undergo periodic molt, during which they replace old feathers. However, unlike other birds, penguins replace their entire plumage within a short period while fasting ashore. During molt, king penguins (Aptenodytes patagonicus) lose half of their initial body mass, most importantly their insulating subcutaneous fat and half of their pectoral muscle mass. The latter might challenge their capacity to generate and sustain a sufficient mechanical power output to swim to distant food sources and propel themselves to great depth for successful prey capture. To investigate the effects of the annual molt fast on their dive/foraging performance, we studied various dive/foraging parameters and peripheral temperature patterns in immature king penguins across two molt cycles, after birds had spent their first and second year at sea, using implanted data-loggers. We found that the dive/foraging performance of immature king penguins was significantly reduced during post-molt foraging trips. Dive and bottom duration for a given depth were shorter during post-molt and post-dive surface interval duration was longer, reducing overall dive efficiency and underwater foraging time. We attribute this decline to the severe physiological changes that birds undergo during their annual molt. Peripheral temperature patterns differed greatly between pre- and post-molt trips, indicating the loss of the insulating subcutaneous fat layer during molt. Peripheral perfusion, as inferred from peripheral temperature, was restricted to short periods at night during pre-molt but occurred throughout extended periods during post-molt, reflecting the need to rapidly deposit an insulating fat layer during the latter period.
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Affiliation(s)
- Manfred R. Enstipp
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Charles-André Bost
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Céline Le Bohec
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
- Centre Scientifique de Monaco, Département de Biologie Polaire, MC 98000, Monaco
| | - Caroline Bost
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Robin Laesser
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Yvon Le Maho
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
- Centre Scientifique de Monaco, Département de Biologie Polaire, MC 98000, Monaco
| | - Henri Weimerskirch
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Yves Handrich
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
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Orgeret F, Péron C, Enstipp MR, Delord K, Weimerskirch H, Bost CA. Exploration during early life: distribution, habitat and orientation preferences in juvenile king penguins. MOVEMENT ECOLOGY 2019; 7:29. [PMID: 31660153 PMCID: PMC6805568 DOI: 10.1186/s40462-019-0175-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 09/24/2019] [Indexed: 05/21/2023]
Abstract
BACKGROUND The early life of marine apex predators is poorly known, particularly for diving species. The orientation and foraging skills are presumably less developed in juveniles than in adults, especially during their first year at sea when juveniles might disperse further than adults. METHODS Over two years of monitoring, we tracked the movements of 17 juvenile king penguins (Aptenodytes patagonicus, ~ 1 year old) using satellite relay tags from Crozet Archipelago (Southern Indian Ocean), starting when birds left their natal colony for the first time. For comparison we also tagged 6 non-breeding adults, which at that stage, similar to juveniles, are unhampered by reproductive constraints and might roam further than breeders. We used a combination of cluster analysis and habitat modelling to investigate and compare the movement patterns and habitat use of experienced (non-breeding adults) and non-experienced (juveniles) individuals. RESULTS While juvenile penguins and non-breeding adults followed similar routes, the movements by adults started later in the season and ranged over a considerably smaller area than juveniles. Net squared displacement analysis revealed that both groups did not move to a specific wintering area. Changes in direction of juveniles in respect to their departure island were similar and synchronous for both years. Habitat models revealed that foraging behaviour was affected by environmental variables such as wind or current speeds, sea surface temperature, or oceanic productivity, for both stages. Analysis of tracks revealed that birds moved predominately perpendicular or against the main direction of the Antarctic Circumpolar Current and the prevailing wind during austral summer (juveniles only) and autumn (juveniles and non-breeding adults). However, both juveniles and adults were more likely to move against the prevailing winds if productivity increased along their trajectories. CONCLUSIONS The exceptional duration of our tracking study provided unprecedented insights into the distribution, habitat preferences and orientation of two poorly known life history stages of an expert avian diver. Our study suggests that juveniles might use both innate and learnt skills to reach profitable foraging areas during their first year at sea, which is critical in long-lived species.
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Affiliation(s)
- F. Orgeret
- Centre d’Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - C. Péron
- Laboratoire de Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), MNHN, CNRS, IRD, SU, UCN, UA. CP 26, 43 rue Cuvier, 75231 Paris Cedex 05, France
| | - M. R. Enstipp
- Département Ecologie, Physiologie et Ethologie, Université de Strasbourg, CNRS, IPHC, UMR 7178, F-67000 Strasbourg, France
| | - K. Delord
- Centre d’Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - H. Weimerskirch
- Centre d’Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - C. A. Bost
- Centre d’Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
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Noren SR, Poll CP, Edwards MS. Body Growth and Rapid Hematological Development Support Breath Hold of Baby Belugas (Delphinapterus leucas) during Subice Transit. Physiol Biochem Zool 2017; 91:691-704. [PMID: 29125799 DOI: 10.1086/694920] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Body size and oxygen stores in the blood and muscle set breath-hold limits in marine mammals, yet these characteristics are understudied in immature cetaceans. We examined body mass and hematology from birth through adulthood in beluga whales (Delphinapterus leucas). At birth, body mass was 8% and 6% of the maximum mass recorded for adult females and males, respectively. Body mass then increased rapidly, approaching an asymptote around 12 yr for females and 18 yr for males. Interestingly, red blood cell counts, hemoglobin content, and hematocrit levels decreased after birth; this neonatal anemia was reversed as levels increased after 2 mo postpartum. Mature levels were obtained at approximately 8, 9, and 11 mo postpartum, respectively. Neonatal mean corpuscular hemoglobin also increased with ontogeny; mature levels were achieved by approximately 13 mo after birth. In contrast, mean corpuscular volume and mean corpuscular hemoglobin concentration demonstrated a significant but subtle increase throughout ontogeny. Our results indicate that postnatal maturation was required and that maturation occurred far earlier than the age at weaning (i.e., 2-3 yr postpartum). This is atypical of marine mammals, which generally achieve mature hemoglobin levels at weaning. Hematological maturation before maternal independence undoubtedly supports the prolonged breath holds of young belugas transiting under sea ice. This assessment enhances our knowledge of cetacean physiology and provides important inputs for determining age-specific dive capacity, yielding insights into age-specific flexibility to alter underwater behaviors, as will be required for future regime shifts and disturbances.
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Enstipp MR, Bost CA, Le Bohec C, Bost C, Le Maho Y, Weimerskirch H, Handrich Y. Apparent changes in body insulation of juvenile king penguins suggest an energetic challenge during their early life at sea. J Exp Biol 2017; 220:2666-2678. [DOI: 10.1242/jeb.160143] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/17/2017] [Indexed: 11/20/2022]
Abstract
ABSTRACT
Little is known about the early life at sea of marine top predators, like deep-diving king penguins (Aptenodytes patagonicus), although this dispersal phase is probably a critical phase in their life. Apart from finding favourable foraging sites, they have to develop effective prey search patterns as well as physiological capacities that enable them to capture sufficient prey to meet their energetic needs. To investigate the ontogeny of their thermoregulatory responses at sea, we implanted 30 juvenile king penguins and 8 adult breeders with a small data logger that recorded pressure and subcutaneous temperature continuously for up to 2.5 years. We found important changes in the development of peripheral temperature patterns of foraging juvenile king penguins throughout their first year at sea. Peripheral temperature during foraging bouts fell to increasingly lower levels during the first 6 months at sea, after which it stabilized. Most importantly, these changes re-occurred during their second year at sea, after birds had fasted for ∼4 weeks on land during their second moult. Furthermore, similar peripheral temperature patterns were also present in adult birds during foraging trips throughout their breeding cycle. We suggest that rather than being a simple consequence of concurrent changes in dive effort or an indication of a physiological maturation process, these seasonal temperature changes mainly reflect differences in thermal insulation. Heat loss estimates for juveniles at sea were initially high but declined to approximately half after ∼6 months at sea, suggesting that juvenile king penguins face a strong energetic challenge during their early oceanic existence.
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Affiliation(s)
- Manfred R. Enstipp
- Université de Strasbourg, CNRS, IPHC, Département Ecologie, Physiologie et Ethologie, UMR 7178, F-67000 Strasbourg, France
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Charles-André Bost
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Céline Le Bohec
- Université de Strasbourg, CNRS, IPHC, Département Ecologie, Physiologie et Ethologie, UMR 7178, F-67000 Strasbourg, France
- Centre Scientifique de Monaco, Département de Biologie Polaire, 98000 MC, Monaco
- Laboratoire International Associé (LIA 647 BioSensib – CSM-CNRS-Unistra), 98000 MC, Monaco
| | - Caroline Bost
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Yvon Le Maho
- Université de Strasbourg, CNRS, IPHC, Département Ecologie, Physiologie et Ethologie, UMR 7178, F-67000 Strasbourg, France
- Centre Scientifique de Monaco, Département de Biologie Polaire, 98000 MC, Monaco
- Laboratoire International Associé (LIA 647 BioSensib – CSM-CNRS-Unistra), 98000 MC, Monaco
| | - Henri Weimerskirch
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Yves Handrich
- Université de Strasbourg, CNRS, IPHC, Département Ecologie, Physiologie et Ethologie, UMR 7178, F-67000 Strasbourg, France
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Noren SR, West K. Muscle biochemistry of a pelagic delphinid (Stenella longirostris longirostris): insight into fishery-induced separation of mothers and calves. J Exp Biol 2017; 220:1490-1496. [DOI: 10.1242/jeb.153668] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/01/2017] [Indexed: 11/20/2022]
Abstract
ABSTRACT
The length of time required for postnatal maturation of the locomotor muscle (longissimus dorsi) biochemistry [myoglobin (Mb) content and buffering capacity] in marine mammals typically varies with nursing duration, but it can be accelerated by species-specific behavioral demands, such as deep-diving and sub-ice transit. We examined how the swimming demands of a pelagic lifestyle influence postnatal maturation of Mb and buffering capacity in spinner dolphins (Stenella longirostris longirostris). Mb content of newborn (1.16±0.07 g Mb per 100 g wet muscle mass, n=6) and juvenile (2.77±0.22 g per 100 g, n=4) spinner dolphins were only 19% and 46% of adult levels (6.00±0.74 g per 100 g, n=6), respectively. At birth, buffering capacity was 52.70±4.48 slykes (n=6) and increased to 78.53±1.91 slykes (n=6) once a body length of 141 cm was achieved, representing 1.6- to 2.0-year-old dolphins. Based on the age of weaning (1.3–1.6 years post-partum), muscle maturation occurred just after weaning as described for coastal bottlenose dolphins (Tursiops truncatus). Thus, a pelagic lifestyle does not promote rapid maturation of muscle biochemistry. Rather, it promotes enhanced muscle biochemistry: newborn and adult spinner dolphins had four- and two-times greater Mb contents than newborn and adult bottlenose dolphins, respectively. Indeed, adult levels rivaled those of deep-diving cetaceans. Nonetheless, the relatively underdeveloped muscle biochemistry of calves likely contributes to documented mother–calf separations for spinner dolphins chased by the tuna purse-seine fishery.
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Affiliation(s)
- Shawn R. Noren
- Institute of Marine Science, University of California, Santa Cruz, Center for Ocean Health, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Kristi West
- College of Natural and Computational Sciences, Hawaii Pacific University, 45-045 Kamehameha Hwy., Kaneohe, HI 96744, USA
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11
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Orgeret F, Weimerskirch H, Bost CA. Early diving behaviour in juvenile penguins: improvement or selection processes. Biol Lett 2016; 12:20160490. [PMID: 27484650 PMCID: PMC5014042 DOI: 10.1098/rsbl.2016.0490] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 07/08/2016] [Indexed: 11/12/2022] Open
Abstract
The early life stage of long-lived species is critical to the viability of population, but is poorly understood. Longitudinal studies are needed to test whether juveniles are less efficient foragers than adults as has been hypothesized. We measured changes in the diving behaviour of 17 one-year-old king penguins Aptenodytes patagonicus at Crozet Islands (subantartic archipelago) during their first months at sea, using miniaturized tags that transmitted diving activity in real time. We also equipped five non-breeder adults with the same tags for comparison. The data on foraging performance revealed two groups of juveniles. The first group made shallower and shorter dives that may be indicative of early mortality while the second group progressively increased their diving depths and durations, and survived the first months at sea. This surviving group of juveniles required the same recovery durations as adults, but typically performed shallower and shorter dives. There is thereby a relationship between improved diving behaviour and survival in young penguins. This long period of improving diving performance in the juvenile life stage is potentially a critical period for the survival of deep avian divers and may have implications for their ability to adapt to environmental change.
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Affiliation(s)
- Florian Orgeret
- Centre d'Etudes Biologiques de Chize UMR 7372 du CNRS-Universite de La Rochelle, 79360 Villiers-en-Bois, France
| | - Henri Weimerskirch
- Centre d'Etudes Biologiques de Chize UMR 7372 du CNRS-Universite de La Rochelle, 79360 Villiers-en-Bois, France
| | - Charles-André Bost
- Centre d'Etudes Biologiques de Chize UMR 7372 du CNRS-Universite de La Rochelle, 79360 Villiers-en-Bois, France
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12
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Hückstädt LA, Tift MS, Riet-Sapriza F, Franco-Trecu V, Baylis AMM, Orben RA, Arnould JPY, Sepulveda M, Santos-Carvallo M, Burns JM, Costa DP. Regional variability in diving physiology and behavior in a widely distributed air-breathing marine predator, the South American sea lion (Otaria byronia). ACTA ACUST UNITED AC 2016; 219:2320-30. [PMID: 27247316 DOI: 10.1242/jeb.138677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 05/17/2016] [Indexed: 11/20/2022]
Abstract
Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Because of their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral and physiological plasticity of a marine predator in different environments. We measured the oxygen stores and diving behavior of South American sea lions throughout most of its range, allowing us to demonstrate that diving ability and behavior vary across its range. We found no significant differences in mass-specific blood volumes of sea lions among field sites and a negative relationship between mass-specific oxygen storage and size, which suggests that exposure to different habitats and geographical locations better explains oxygen storage capacities and diving capability in South American sea lions than body size alone. The largest animals in our study (individuals from Uruguay) were the shallowest and shortest duration divers, and had the lowest mass-specific total body oxygen stores, while the deepest and longest duration divers (individuals from southern Chile) had significantly larger mass-specific oxygen stores, despite being much smaller animals. Our study suggests that the physiology of air-breathing diving predators is not fixed, but that it can be adjusted, to a certain extent, depending on the ecological setting and or habitat. These adjustments can be thought of as a 'training effect': as the animal continues to push its physiological capacity through greater hypoxic exposure, its breath-holding capacity increases.
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Affiliation(s)
- Luis A Hückstädt
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Long Marine Laboratory, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Michael S Tift
- Scripps Institution of Oceanography, University of California San Diego, Center for Marine Biodiversity and Biomedicine, 8655 Kennel Way, La Jolla, CA 92037, USA
| | - Federico Riet-Sapriza
- Laboratorio de Ecologia Molecular de Vertebrados Acuaticos (LEMVA), Departamento de Ciencias Biologicas, Facultad de Ciencias, Universidad de Los Andes, Carrera 1E, #18A-10, Bogota, Colombia
| | - Valentina Franco-Trecu
- Departamento de Ecología y Evolución Facultad de Ciencias, Universidad de la República, Iguá 4225 Esq. Mataojo C.P, 11400 Montevideo, Uruguay
| | - Alastair M M Baylis
- South Atlantic Environmental Research Institute, Stanley FIQQ1ZZ, Falkland Islands School of Life and Environmental Sciences, Deakin University, Warrnambool Campus, Geelong, Australia
| | - Rachael A Orben
- Hatfield Marine Science Center, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
| | - John P Y Arnould
- School of Life and Environmental Sciences, Deakin University, Burwood Campus, Geelong, Australia
| | - Maritza Sepulveda
- Centro de Investigación y Gestión en Recursos Naturales (CIGREN), Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Avenida Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - Macarena Santos-Carvallo
- Centro de Investigación y Gestión en Recursos Naturales (CIGREN), Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Avenida Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - Jennifer M Burns
- Department of Biological Sciences, University of Alaska Anchorage. 3211 Providence Drive Anchorage, AK 99508, USA
| | - Daniel P Costa
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Long Marine Laboratory, 100 Shaffer Road, Santa Cruz, CA 95060, USA
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13
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Le Vaillant M, Ropert-Coudert Y, Le Maho Y, Le Bohec C. Individual parameters shape foraging activity in breeding king penguins. Behav Ecol 2016. [DOI: 10.1093/beheco/arv146] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Thomas A, Ono K. Diving Related Changes in the Blood Oxygen Stores of Rehabilitating Harbor Seal Pups (Phoca vitulina). PLoS One 2015; 10:e0128930. [PMID: 26061662 PMCID: PMC4465541 DOI: 10.1371/journal.pone.0128930] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 05/01/2015] [Indexed: 11/18/2022] Open
Abstract
Harbor seal (Phoca vitulina) pups begin diving within hours of birth, stimulating the development of the blood oxygen (O2) stores necessary to sustain underwater aerobic metabolism. Since harbor seals experience a brief nursing period, the early-life development of these blood O2 stores is necessary for successful post-weaning foraging. If mothers and pups become prematurely separated, the pup may be transported to a wildlife rehabilitation center for care. Previous studies suggest that the shallow pools and lack of diving in rehabilitation facilities may lead to under-developed blood O2 stores, but diving behavior during rehabilitation has not been investigated. This study aimed to simultaneously study the diving behaviors and blood O2 store development of rehabilitating harbor seal pups. Standard hematology measurements (Hct, Hb, RBC, MCV, MCH, MCHC) were taken to investigate O2 storage capacity and pups were equipped with time-depth recorders to investigate natural diving behavior while in rehabilitation. Linear mixed models of the data indicate that all measured blood parameters changed with age; however, when compared to literature values for wild harbor seal pups, rehabilitating pups have smaller red blood cells (RBCs) that can store less hemoglobin (Hb) and subsequently, less O2, potentially limiting their diving capabilities. Wild pups completed longer dives at younger ages (maximum reported <25 days of age: 9 min) in previous studies than the captive pups in this study (maximum <25 days of age: 2.86 min). However, captivity may only affect the rate of development, as long duration dives were observed (maximum during rehabilitation: 13.6 min at 89 days of age). Further, this study suggests that there may be a positive relationship between RBC size and the frequency of long duration dives. Thus, rehabilitating harbor seal pups should be encouraged to make frequent, long duration dives to prepare themselves for post-release foraging.
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Affiliation(s)
- Amber Thomas
- Department of Marine Sciences, University of New England, Biddeford, Maine, United States of America
| | - Kathryn Ono
- Department of Marine Sciences, University of New England, Biddeford, Maine, United States of America
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15
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Wright TJ, Davis RW. Myoglobin oxygen affinity in aquatic and terrestrial birds and mammals. ACTA ACUST UNITED AC 2015; 218:2180-9. [PMID: 25987728 DOI: 10.1242/jeb.119321] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 05/08/2015] [Indexed: 12/30/2022]
Abstract
Myoglobin (Mb) is an oxygen binding protein found in vertebrate skeletal muscle, where it facilitates intracellular transport and storage of oxygen. This protein has evolved to suit unique physiological needs in the muscle of diving vertebrates that express Mb at much greater concentrations than their terrestrial counterparts. In this study, we characterized Mb oxygen affinity (P50) from 25 species of aquatic and terrestrial birds and mammals. Among diving species, we tested for correlations between Mb P50 and routine dive duration. Across all species examined, Mb P50 ranged from 2.40 to 4.85 mmHg. The mean P50 of Mb from terrestrial ungulates was 3.72±0.15 mmHg (range 3.70-3.74 mmHg). The P50 of cetaceans was similar to terrestrial ungulates ranging from 3.54 to 3.82 mmHg, with the exception of the melon-headed whale, which had a significantly higher P50 of 4.85 mmHg. Among pinnipeds, the P50 ranged from 3.23 to 3.81 mmHg and showed a trend for higher oxygen affinity in species with longer dive durations. Among diving birds, the P50 ranged from 2.40 to 3.36 mmHg and also showed a trend of higher affinities in species with longer dive durations. In pinnipeds and birds, low Mb P50 was associated with species whose muscles are metabolically active under hypoxic conditions associated with aerobic dives. Given the broad range of potential globin oxygen affinities, Mb P50 from diverse vertebrate species appears constrained within a relatively narrow range. High Mb oxygen affinity within this range may be adaptive for some vertebrates that make prolonged dives.
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Affiliation(s)
- Traver J Wright
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX 77551, USA Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Randall W Davis
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX 77551, USA Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843, USA
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16
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Individual repeatability of foraging behaviour in a marine predator, the great cormorant, Phalacrocorax carbo. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.02.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Thometz NM, Murray MJ, Williams TM. Ontogeny of Oxygen Storage Capacity and Diving Ability in the Southern Sea Otter (Enhydra lutris nereis): Costs and Benefits of Large Lungs. Physiol Biochem Zool 2015; 88:311-27. [DOI: 10.1086/681019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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18
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Minias P. The use of haemoglobin concentrations to assess physiological condition in birds: a review. CONSERVATION PHYSIOLOGY 2015; 3:cov007. [PMID: 27293692 PMCID: PMC4778452 DOI: 10.1093/conphys/cov007] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 02/02/2015] [Accepted: 02/04/2015] [Indexed: 05/05/2023]
Abstract
Total blood haemoglobin concentration is increasingly being used to assess physiological condition in wild birds, although it has not been explicitly recognized how reliably this parameter reflects different components of individual quality. Thus, I reviewed over 120 published studies linking variation in haemoglobin concentrations to different measures of condition and other phenotypic or ecological traits. In most of the studied avian species, haemoglobin concentrations were positively correlated with other commonly used indices of condition, such as body mass and fat loads, as well as with quality of the diet. Also, chick haemoglobin concentrations reliably reflected the intensity of nest infestation by parasitic arthropods, and haemoglobin was suggested to reflect parasitism by haematophagous ectoparasites much more precisely than haematocrit. There was also some evidence for the negative effect of helminths on haemoglobin levels in adult birds. Finally, haemoglobin concentrations were found to correlate with such fitness-related traits as timing of arrival at breeding grounds, timing of breeding, egg size, developmental stability and habitat quality, although these relationships were not always consistent between species. In consequence, I recommend the total blood haemoglobin concentration as a relatively robust indicator of physiological condition in birds, although this parameter is also strongly affected by age, season and the process of moult. Thus, researchers are advised to control fully for these confounding effects while using haemoglobin concentrations as a proxy of physiological condition in both experimental and field studies on birds.
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Affiliation(s)
- Piotr Minias
- Department of Teacher Training and Biodiversity Studies, University of Łódź, Banacha 1/3, Łódź 90–237, Poland
- Corresponding author:
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19
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Noren SR, Jay CV, Burns JM, Fischbach AS. Rapid maturation of the muscle biochemistry that supports diving in pacific walruses (Odobenus rosmarus divergens). J Exp Biol 2015; 218:3319-29. [PMID: 26347559 DOI: 10.1242/jeb.125757] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 08/24/2015] [Indexed: 11/20/2022]
Abstract
Physiological constraints dictate animals' abilities to exploit habitats. For marine mammals, it is important to quantify physiological limits that influence diving and their ability to alter foraging behaviors. We characterized age-specific dive limits of walruses by measuring anaerobic (acid buffering capacity) and aerobic (myoglobin content) capacities of the muscles that power hind (longissimus dorsi) and fore (supraspinatus) flipper propulsion. Mean buffering capacities were similar across muscles and age classes (a fetus, 5 neonatal calves, a 3-month old, and 20 adults), ranging from 41.31 – 54.14 slykes and 42.00 – 46.93 slykes in the longissimus and supraspinatus, respectively. Mean myoglobin in the fetus and neonatal calves fell within a narrow range (longissimus: 0.92 – 1.68 g 100 g wet muscle mass−1; supraspinatus: 0.88 – 1.64 g wet muscle mass−1). By 3 months postpartum, myoglobin in the longissimus increased by 79%, but levels in the supraspinatus remained unaltered. From 3-months postpartum to adulthood, myoglobin increased by an additional 26% in the longissimus and increased by 126% in the supraspinatus; myoglobin remained greater in the longissimus compared to the supraspinatus. Walruses are unique among marine mammals because they are born with mature muscle acid buffering capacity and attain mature myoglobin content early in life. Despite rapid physiological development, small body size limits the diving capacity of immature walruses and extreme sexual dimorphism reduces the diving capacity of adult females compared to adult males. Thus, free-ranging immature walruses likely exhibit the shortest foraging dives while adult males are capable of the longest foraging dives.
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Affiliation(s)
- Shawn R. Noren
- Institute of Marine Science, University of California, Santa Cruz, Center for Ocean Health, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Chadwick V. Jay
- U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - Jennifer M. Burns
- University of Alaska, Anchorage, Department of Biological Sciences, CPSB 202C, 3101 Science Circle, University of Alaska, Anchorage, AK 99508, USA
| | - Anthony S. Fischbach
- U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
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20
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Living in the fast lane: rapid development of the locomotor muscle in immature harbor porpoises (Phocoena phocoena). J Comp Physiol B 2014; 184:1065-76. [DOI: 10.1007/s00360-014-0854-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 07/29/2014] [Accepted: 08/05/2014] [Indexed: 10/24/2022]
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21
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Fine-scale spatial age segregation in the limited foraging area of an inshore seabird species, the little penguin. Oecologia 2014; 176:399-408. [PMID: 25038901 DOI: 10.1007/s00442-014-3018-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 06/27/2014] [Indexed: 10/25/2022]
Abstract
Competition for food resources can result in spatial and dietary segregation among individuals from the same species. Few studies have looked at such segregations with the combined effect of sex and age in species with short foraging ranges. In this study we examined the 3D spatial use of the environment in a species with a limited foraging area. We equipped 26 little penguins (Eudyptula minor) of known age, sex, and breeding output with GPS (location) and accelerometer (body acceleration and dive depth) loggers. We obtained dietary niche information from the isotopic analysis of blood tissue. We controlled for confounding factors of foraging trip length and food availability by sampling adults at guard stage when parents usually make one-day trips. We observed a spatial segregation between old (>11 years old) and middle-aged penguins (between 5 and 11 years old) in the foraging area. Old penguins foraged closer to the shore, in shallower water. Despite observing age-specific spatial segregation, we found no differences in the diving effort and foraging efficiency between age classes and sexes. Birds appeared to target similar prey types, but showed age-specific variation in their isotopic niche width. We hypothesize that this age-specific segregation was primarily determined by a "cohort effect" that would lead individuals sharing a common life history (i.e. having fledged and dispersed around the same age) to forage preferentially together or to share similar foraging limitations.
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22
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Tift MS, Ranalli EC, Houser DS, Ortiz RM, Crocker DE. Development enhances hypometabolism in northern elephant seal pups ( Mirounga angustirostris). Funct Ecol 2013; 27. [PMID: 24187422 DOI: 10.1111/1365-2435.12111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Investigation into the development of oxygen storage capacity in air-breathing marine predators has been performed, but little is known about the development of regulatory factors that influence oxygen utilization. Strategies for efficiently using oxygen stores should enable marine predators to optimize time spent foraging underwater.We describe the developmental patterns of oxygen use during voluntary breath-holds in northern elephant seals (Mirounga angustirostris) at 2 and 7 weeks post-weaning. We measured 1) changes in oxygen consumption (VO2), and 2) changes in venous pH, partial pressure of oxygen (pO2), haemoglobin saturation (sO2), oxygen content (O2ct), partial pressure of carbon dioxide (pCO2), haematocrit (Hct) and total haemoglobin (tHb). To examine the effect of the dive response on the development of oxygen utilization, voluntary breath-hold experiments were conducted in and out of water.Suppression of VO2 during voluntary breath-holds increased significantly between 2 and 7 weeks post-weaning, reaching a maximum suppression of 53% below resting metabolic rate and 56% below Kleiber's standard metabolic rate. From 2 to 7 weeks post-weaning, breath-hold VO2 was reduced by 52%. Between the two age classes, this equates to a mean breath-hold VO2 reduction of 16% from resting VO2. Breath-hold VO2 also declined with increasing breath-hold duration, but there was no direct effect of voluntary submergence on reducing VO2.Age did not influence rates of venous pO2 depletion during breath-holds. However, voluntary submergence did result in slower pO2 depletion rates when compared to voluntary terrestrial apnoeas. The differences in whole body VO2 during breath-holds (measured at recovery) and venous pO2 (reflective of tissue O2-use measured during breath-holds), likely reflects metabolic suppression in hypoxic, vasoconstricted tissues.Consistent pCO2 values at the end of all voluntary breath-holds (59.0 ± 0.7 mmHg) suggests the physiological cue for stimulating respiration in northern elephant seal pups is the accumulation of CO2.Oxygen storage capacity and metabolic suppression directly limit diving capabilities and may influence foraging success in low-weaning weight seals forced to depart to sea prior to achieving full developmental diving capacity.
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Affiliation(s)
- Michael S Tift
- Department of Biology, Sonoma State University, 1801 East Cotati Ave, Rohnert Park, CA 94928, USA
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23
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Ponganis PJ, Welch TJ, Welch LS, Stockard TK. Myoglobin production in emperor penguins. J Exp Biol 2010; 213:1901-6. [DOI: 10.1242/jeb.042093] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SUMMARY
Increased oxygen storage is essential to the diving capacities of marine mammals and seabirds. However, the molecular mechanisms underlying this adaptation are unknown. Myoglobin (Mb) and Mb mRNA concentrations were analyzed in emperor penguin (Aptenodytes forsteri) adults and chicks with spectrophotometric and RNase protection assays to evaluate production of their large Mb-bound O2 stores. Mean pectoral Mb concentration and Mb mRNA content increased throughout the pre-fledging period and were 15-fold and 3-fold greater, respectively, in adults than in 3.5 month old chicks. Mean Mb concentration in 5.9 month old juveniles was 2.7±0.4 g 100 g−1 muscle (44% that of wild adults), and in adults that had been captive all their lives it was 3.7±0.1 g 100 g−1 muscle. The Mb and Mb mRNA data are consistent with regulation of Mb production at the level of transcription as in other animals. Significant Mb and Mb mRNA production occurred in chicks and young juveniles even without any diving activity. The further increase in adult Mb concentrations appears to require the exercise/hypoxia of diving because Mb concentration in captive, non-diving adults only reached 60% of that of wild adults. The much greater relative increase in Mb concentration than in Mb mRNA content between young chicks and adults suggests that there is not a simple 1:1 relationship between Mb mRNA content and Mb concentration. Nutritional limitation in young chicks and post-transcriptional regulation of Mb concentration may also be involved.
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Affiliation(s)
- P. J. Ponganis
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0204, USA
| | - T. J. Welch
- National Center for Cool and Cold Water Aquaculture, Agricultural Research Service, USDA, Kearneysville, WV 25430, USA
| | - L. S. Welch
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0204, USA
| | - T. K. Stockard
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0204, USA
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24
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Villegas-Amtmann S, Costa DP. Oxygen stores plasticity linked to foraging behaviour and pregnancy in a diving predator, the Galapagos sea lion. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2009.01685.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Ludvigsen S, Folkow LP. Differences in in vitro cerebellar neuronal responses to hypoxia in eider ducks, chicken and rats. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2009; 195:1021-30. [DOI: 10.1007/s00359-009-0476-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Revised: 07/19/2009] [Accepted: 08/31/2009] [Indexed: 12/11/2022]
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26
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Lestyk KC, Folkow LP, Blix AS, Hammill MO, Burns JM. Development of myoglobin concentration and acid buffering capacity in harp (Pagophilus groenlandicus) and hooded (Cystophora cristata) seals from birth to maturity. J Comp Physiol B 2009; 179:985-96. [PMID: 19565249 DOI: 10.1007/s00360-009-0378-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/08/2009] [Accepted: 06/12/2009] [Indexed: 12/01/2022]
Abstract
Pinnipeds rely on muscle oxygen stores to help support aerobic diving, therefore muscle maturation may influence the behavioral ecology of young pinnipeds. To investigate the pattern of muscle development, myoglobin concentration ([Mb]) and acid buffering ability (beta) was measured in ten muscles from 23 harp and 40 hooded seals of various ages. Adult [Mb] ranged from 28-97 to 35-104 mg g tissue(-1) in harp and hooded seals, respectively, with values increasing from the cervical, non-swimming muscles to the main swimming muscles of the lumbar region. Neonatal and weaned pup muscles exhibited lower (approximately 30% adult values) and less variable [Mb] across the body than adults. In contrast, adult beta showed little regional variation (60-90 slykes), while high pup values (approximately 75% adult values) indicate significant in utero development. These findings suggest that intra-uterine conditions are sufficiently hypoxic to stimulate prenatal beta development, but that [Mb] development requires additional postnatal signal such as exercise, and/or growth factors. However, because of limited development in both beta and [Mb] during the nursing period, pups are weaned with muscles with lower aerobic and anaerobic capacities than those of adults.
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Affiliation(s)
- Keri C Lestyk
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA.
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27
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Zeno RL, Crocker DE, Hassrick JL, Allen SG, Costa DP. Development of foraging behavior in juvenile northern elephant seals. J Zool (1987) 2008. [DOI: 10.1111/j.1469-7998.2007.00371.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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FOWLER SL, COSTA DP, ARNOULD JPY, GALES NJ, BURNS JM. Ontogeny of oxygen stores and physiological diving capability in Australian sea lions. Funct Ecol 2007. [DOI: 10.1111/j.1365-2435.2007.01295.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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29
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Burns JM, Lestyk KC, Folkow LP, Hammill MO, Blix AS. Size and distribution of oxygen stores in harp and hooded seals from birth to maturity. J Comp Physiol B 2007; 177:687-700. [PMID: 17576570 DOI: 10.1007/s00360-007-0167-2] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 04/25/2007] [Accepted: 04/26/2007] [Indexed: 11/29/2022]
Abstract
Pinnipeds rely primarily on oxygen stores in blood and muscles to support aerobic diving; therefore rapid development of body oxygen stores (TBO(2)) is crucial for pups to transition from nursing to independent foraging. Here, we investigate TBO(2) development in 45 harp (Pagophilus groenlandicus) and 46 hooded (Cystophora cristata) seals ranging in age from neonates to adult females. We found that hooded seal adults have the largest TBO(2) stores yet reported (89.5 ml kg(-1)), while harp seal adults have values more similar to other phocids (71.6 ml kg(-1)). In adults, large TBO(2) stores resulted from large blood volume (harp169, hood 194 ml kg(-1)) and high muscle Mb content (harp 86.0, hood 94.8 mg g(-1)). In contrast, pups of both species had significantly lower mass-specific TBO(2 )stores than adults, and stores declined rather than increased during the nursing period. This decline was due to a reduction in mass-specific blood volume and the absence of an increase in the low Mb levels (harp 21.0, hood 31.5 mg g(-1)). Comparisons with other phocid species suggests that the pattern of blood and muscle development in the pre- and post-natal periods varies with terrestrial period, and that muscle maturation rates may influence the length of the postweaning fast. However, final maturation of TBO(2) stores does not take place until after foraging begins.
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Affiliation(s)
- J M Burns
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA.
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Abstract
All mammals and birds must develop effective strategies to cope with reduced oxygen availability. These animals achieve tolerance to acute and chronic hypoxia by (a) reductions in metabolism, (b) the prevention of cellular injury, and (c) the maintenance of functional integrity. Failure to meet any one of these tasks is detrimental. Birds and mammals accomplish this triple task through a highly coordinated, systems-level reconfiguration involving the partial shutdown of some but not all organs. This reconfiguration is achieved through a similarly complex reconfiguration at the cellular and molecular levels. Reconfiguration at these various levels depends on numerous factors that include the environment, the degree of hypoxic stress, and developmental, behavioral, and ecological conditions. Although common molecular strategies exist, the cellular and molecular changes in any given cell are very diverse. Some cells remain metabolically active, whereas others shut down or rely on anaerobic metabolism. This cellular shutdown is temporarily regulated, and during hypoxic exposure, active cellular networks must continue to control vital functions. The challenge for future research is to explore the cellular mechanisms and conditions that transform an organ or a cellular network into a hypometabolic state, without loss of functional integrity. Much can be learned in this respect from nature: Diving, burrowing, and hibernating animals living in diverse environments are masters of adaptation and can teach us how to deal with hypoxia, an issue of great clinical significance.
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Affiliation(s)
- Jan-Marino Ramirez
- Department of Organismal Biology & Anatomy, University of Chicago, Chicago, Illinois 60637, USA.
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Spence-Bailey LM, Verrier D, Arnould JPY. The physiological and behavioural development of diving in Australian fur seal (Arctocephalus pusillus doriferus) pups. J Comp Physiol B 2007; 177:483-94. [PMID: 17294194 DOI: 10.1007/s00360-007-0146-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Revised: 01/05/2007] [Accepted: 01/11/2007] [Indexed: 10/23/2022]
Abstract
The physiological and behavioural development of diving was examined in Australian fur seal (Arctocephalus pusillus doriferus) pups to assess whether animals at weaning are capable of exploiting the same resources as adult females. Haematocrit, haemoglobin and myoglobin contents all increased throughout pup development though total body oxygen stores reached only 71% of adult female levels just prior to weaning. Oxygen storage components, however, did not develop at the same pace. Whereas blood oxygen stores had reached adult female levels by 9 months of age, muscle oxygen stores were slower to develop, reaching only 23% of adult levels by this age. Increases in diving behaviour corresponded to the physiological changes observed. Pups spent little time (<8%) in the water prior to moulting (age 1-2 months) whereas following the moult, they spent >27% of time in the water and made mid-water dives (maximum depth 35.7 +/- 2.9 m) with durations of 0.35 +/- 0.03 min. By 9 months (just prior to weaning), 30.5 +/- 9.3% of all dives performed were U-shaped benthic dives (maximum depth 65.0 +/- 6.0 m) with mean durations of 0.87 +/- 0.25 min, significantly shorter than those of adult females. These results suggest that while Australian fur seal pups approaching the age of weaning are able to reach similar depths as adult females, they do not have the physiological capacity to remain at these depths for sufficient durations to exploit them to the same efficiency.
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Affiliation(s)
- L M Spence-Bailey
- School of Life and Environmental Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia.
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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 2007; 210:278-89. [PMID: 17210964 DOI: 10.1242/jeb.02643] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARYA defining physiological capability for air-breathing marine vertebrates is the amount of oxygen that can be stored in tissues and made available during dives. To evaluate the influence of oxygen storage capacity on aerobic diving capacity, we examined the extent to which blood and muscle oxygen stores varied as a function of age, body size and sex in the sexually dimorphic California sea lion, Zalophus californianus. We measured total body oxygen stores, including hematocrit, hemoglobin, MCHC, plasma volume, blood volume and muscle myoglobin in pups through adults of both sexes. Blood and muscle oxygen storage capacity was not fully developed by the end of the dependency period, with blood stores not fully developed until animals were larger juveniles (70 kg; 1.5-2.5 years) and muscle stores not until animals were sub-adult size (125 kg; 4-6 years). Differences in aerobic diving capacity among size classes were reflective of these major milestones in the development of oxygen stores. Male sea lions had greater absolute blood volume than females and reflected the larger mass of males, which became apparent when animals were large juveniles. Adult female sea lions had greater muscle myoglobin concentrations compared to males, resulting in greater mass-specific muscle and total oxygen stores. Delayed development of oxygen stores is consistent with the shallow epi-mesopelagic foraging behavior in this species. We hypothesize that the greater mass-specific oxygen stores of female sea lions compared to males is related to differences in foraging behavior between the sexes.
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Affiliation(s)
- Michael J Weise
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Center for Ocean Health, 100 Shaffer Road, Santa Cruz, CA 95060, USA.
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Clark CA, Burns JM, Schreer JF, Hammill MO. A longitudinal and cross-sectional analysis of total body oxygen store development in nursing harbor seals (Phoca vitulina). J Comp Physiol B 2006; 177:217-27. [PMID: 17089167 DOI: 10.1007/s00360-006-0123-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 08/29/2006] [Accepted: 09/29/2006] [Indexed: 11/25/2022]
Abstract
This study compared the efficacy of longitudinal and cross-sectional sampling regimes for detecting developmental changes in total body oxygen (TBO(2)) stores that accompany behavioral development in free-ranging harbor seal pups. TBO(2) stores were estimated for pup (n = 146) and adult female (n = 20) harbor seals. Age related changes were compared between pups captured repeatedly during the lactation period (longitudinal dataset) and a second group of pups handled only once (cross-sectional dataset). At each handling, hematocrit, hemoglobin, red blood cell count, total plasma volume, blood volume, muscle myoglobin concentration, and blood and muscle oxygen stores were determined. Comparisons across age categories revealed newborn blood oxygen stores were initially elevated, declined to low values by early lactation, and increased through post-weaning. Muscle oxygen stores remained low and constant throughout lactation and only increased significantly post-weaning. Overall TBO(2)stores increased 17% during lactation, and weaned pups had TBO(2)stores that were 55% as large as those of adults. Thus, significant increases in TBO(2) stores must occur after weaning, as pups begin to forage independently. Results from the two sampling schemes did not differ, indicating that the logistically simpler cross-sectional design can be used to monitor physiological development in harbor seals.
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Affiliation(s)
- Cheryl A Clark
- Department of Biological Sciences, University of Alaska Anchorage, 3211 Providence Drive, Anchorage, AK 99508, USA.
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Fowler SL, Costa DP, Arnould JPY, Gales NJ, Kuhn CE. Ontogeny of diving behaviour in the Australian sea lion: trials of adolescence in a late bloomer. J Anim Ecol 2006; 75:358-67. [PMID: 16637989 DOI: 10.1111/j.1365-2656.2006.01055.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
1. Foraging behaviours of the Australian sea lion (Neophoca cinerea) reflect an animal working hard to exploit benthic habitats. Lactating females demonstrate almost continuous diving, maximize bottom time, exhibit elevated field metabolism and frequently exceed their calculated aerobic dive limit. Given that larger animals have disproportionately greater diving capabilities, we wanted to examine how pups and juveniles forage successfully. 2. Time/depth recorders were deployed on pups, juveniles and adult females at Seal Bay Conservation Park, Kangaroo Island, South Australia. Ten different mother/pup pairs were equipped at three stages of development (6, 15 and 23 months) to record the diving behaviours of 51 (nine instruments failed) animals. 3. Dive depth and duration increased with age. However, development was slow. At 6 months, pups demonstrated minimal diving activity and the mean depth for 23-month-old juveniles was only 44 +/- 4 m, or 62% of adult mean depth. 4. Although pups and juveniles did not reach adult depths or durations, dive records for young sea lions indicate benthic diving with mean bottom times (2.0 +/- 0.2 min) similar to those of females (2.1 +/- 0.2 min). This was accomplished by spending higher proportions of each dive and total time at sea on or near the bottom than adults. Immature sea lions also spent a higher percentage of time at sea diving. 5. Juveniles may have to work harder because they are weaned before reaching full diving capability. For benthic foragers, reduced diving ability limits available foraging habitat. Furthermore, as juveniles appear to operate close to their physiological maximum, they would have a difficult time increasing foraging effort in response to reductions in prey. Although benthic prey are less influenced by seasonal fluctuations and oceanographic perturbations than epipelagic prey, demersal fishery trawls may impact juvenile survival by disrupting habitat and removing larger size classes of prey. These issues may be an important factor as to why the Australian sea lion population is currently at risk.
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Affiliation(s)
- Shannon L Fowler
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95064, USA.
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Hindle AG, Senkiw RW, Macarthur RA. Body cooling and the diving capabilities of muskrats (Ondatra zibethicus): a test of the adaptive hypothermia hypothesis. Comp Biochem Physiol A Mol Integr Physiol 2006; 144:232-41. [PMID: 16626985 DOI: 10.1016/j.cbpa.2006.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Accepted: 03/06/2006] [Indexed: 10/24/2022]
Abstract
We tested the hypothesis that immersion hypothermia enhances the diving capabilities of adult and juvenile muskrats by reducing rates of oxygen consumption (V O2). Declines in abdominal body temperature (T(b)) comparable to those observed in nature (0.5-3.5 degrees C) were induced by pre-chilling animals in 6 degrees C water. Pre-chilling did not reduce diving V O2 of any animal tested in 10 degrees C or 30 degrees C water, irrespective of the nature of the dive. Most behavioural indices of dive performance, including average and cumulative dive times, were unaffected by T(b) reduction in adults, but depressed in hypothermic juveniles (200-400 g). Hypothermia reduced diving heart rate only on short (<25s) dives (16% reduction, P=0.01), but did not affect the temporal onset of diving bradycardia. Post-immersion V O2 was higher for pre-chilled than for normothermic muskrats, but the difference became insignificant on longer (>90 s) dives. Our findings suggest that the mild hypothermia experienced by muskrats in nature has minimal effect on diving and post-immersion metabolic costs, and thus has little impact on the dive performance of this northern semi-aquatic mammal.
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Affiliation(s)
- A G Hindle
- Department of Zoology, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
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Richmond JP, Burns JM, Rea LD. Ontogeny of total body oxygen stores and aerobic dive potential in Steller sea lions (Eumetopias jubatus). J Comp Physiol B 2006; 176:535-45. [PMID: 16514541 DOI: 10.1007/s00360-006-0076-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Revised: 02/01/2006] [Accepted: 02/13/2006] [Indexed: 10/25/2022]
Abstract
Two key factors influence the diving and hence foraging ability of marine mammals: increased oxygen stores prolong aerobic metabolism and decreased metabolism slows rate of fuel consumption. In young animals, foraging ability may be physiologically limited due to low total body oxygen stores and high mass specific metabolic rates. To examine the development of dive physiology in Steller sea lions, total body oxygen stores were measured in animals from 1 to 29 months of age and used to estimate aerobic dive limit (ADL). Blood oxygen stores were determined by measuring hematocrit, hemoglobin, and plasma volume, while muscle oxygen stores were determined by measuring myoglobin concentration and total muscle mass. Around 2 years of age, juveniles attained mass specific total body oxygen stores that were similar to those of adult females; however, their estimated ADL remained less than that of adults, most likely due to their smaller size and higher mass specific metabolic rates. These findings indicate that juvenile Steller sea lion oxygen stores remain immature for more than a year, and therefore may constrain dive behavior during the transition to nutritional independence.
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Green JA, Boyd IL, Woakes AJ, Green CJ, Butler PJ. Do seasonal changes in metabolic rate facilitate changes in diving behaviour? ACTA ACUST UNITED AC 2005; 208:2581-93. [PMID: 15961744 DOI: 10.1242/jeb.01679] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Macaroni penguins were implanted with data loggers to record heart rate (fH), abdominal temperature (Tab) and diving depth during their pre-moult trip (summer) and winter migration. The penguins showed substantial differences in diving behaviour between the seasons. During winter, mean and maximum dive duration and dive depth were significantly greater than during summer, but the proportion of dives within the calculated aerobic dive limit (cADL) did not change. Rates of oxygen consumption were estimated from fH. As winter progressed, the rate of oxygen consumption during dive cycles (sVO2DC)) declined significantly and mirrored the pattern of increase in maximum duration and depth. The decline in sVO2DC) was matched by a decline in minimum rate of oxygen consumption (sVO2min)). When sVO2min) was subtracted from sVO2DC), the net cost of diving was unchanged between summer and winter. We suggest that the increased diving capacity demonstrated during the winter was facilitated by the decrease in sVO2min). Abdominal temperature declined during winter but this was not sufficient to explain the decline in sVO2min). A simple model of the interactions between sVO2min), thermal conductance and water temperature shows how a change in the distribution of fat stores and therefore a change in insulation and/or a difference in foraging location during winter could account for the observed reduction in sVO2min) and hence sVO2DC).
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Affiliation(s)
- J A Green
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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Burns JM, Costa DP, Frost K, Harvey JT. Development of body oxygen stores in harbor seals: effects of age, mass, and body composition. Physiol Biochem Zool 2005; 78:1057-68. [PMID: 16228944 DOI: 10.1086/432922] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2005] [Indexed: 11/03/2022]
Abstract
Harbor seal pups are highly precocial and can swim and dive at birth. Such behavioral maturity suggests that they may be born with mature body oxygen stores or that stores develop quickly during the nursing period. To test this hypothesis, we compared the blood and muscle oxygen stores of harbor seal pups, yearlings, and adults. We found that pups had smaller oxygen stores than adults (neonates 57%, weaned pups 75%, and yearlings 90% those of adults), largely because neonatal myoglobin concentrations were low (1.6+/-0.2 g% vs. 3.8+/-0.3 g% for adults) and changed little during the nursing period. In contrast, blood oxygen stores were relatively mature, with nursing pups having hematocrit (55%+/-0.2%), hemoglobin (21.7+/-0.4 g%), and blood volume (12.3+/-0.5 mL/kg) only slightly lower than the corresponding values for adults (57%+/-0.2%, 23.8+/-0.3 g %, and 15.0+/-0.5 mL/kg). Because neonatal pups had relatively high metabolic rates (11.0 mL O2/kg min), their calculated aerobic dive limit was less than 50% that of adults. These results suggest that harbor seals' early aquatic activity is primarily supported by rapid development of blood, with immature muscle oxygen stores and elevated use rates limiting aerobic diving ability.
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Affiliation(s)
- J M Burns
- Department of Biological Sciences, University of Alaska, Anchorage, AK, 99508, USA.
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40
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Noren SR, Iverson SJ, Boness DJ. Development of the blood and muscle oxygen stores in gray seals (Halichoerus grypus): implications for juvenile diving capacity and the necessity of a terrestrial postweaning fast. Physiol Biochem Zool 2005; 78:482-90. [PMID: 15957103 DOI: 10.1086/430228] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2004] [Indexed: 11/03/2022]
Abstract
To successfully transition from nursing to foraging, phocid seal pups must develop adequate diving physiology within the limited time between birth and their first independent foraging trip to sea. We studied the postpartum development of oxygen stores in gray seals (Halichoerus grypus, n=40) to better understand the ontogeny of diving capacity in phocids. Hemoglobin (Hb), hematocrit (Hct), blood volume (BV), and myoglobin (Mb) levels in newborn (3 d postpartum [DPP]) and newly weaned (17+/-0.4 DPP) pups were among the lowest measured across age classes. During the pups' terrestrial postweaning fast (PWF), Hb, Hct, mass-specific BV, and Mb increased by 28%, 21%, 13%, and 29%, respectively, resulting in a 35% increase in total body mass-specific oxygen stores and a 23% increase in calculated aerobic dive limit (CADL). Although Hb and Hct levels at the end of the PWF were nearly identical to those of yearlings, total body mass-specific oxygen stores and CADL of weaned pups departing for sea were only 66%-67% and 32%-62%, respectively, of those for yearlings and adult females. The PWF represents an integral component of the physiological development of diving capacity in phocids; however, newly independent phocids still appear to have limited diving capabilities at the onset of foraging.
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Affiliation(s)
- Shawn R Noren
- Conservation and Research Center, National Zoological Park, Smithsonian Institution, Washington, DC 20008, USA.
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Baird RW, Hanson MB, Dill LM. Factors influencing the diving behaviour of fish-eating killer whales: sex differences and diel and interannual variation in diving rates. CAN J ZOOL 2005. [DOI: 10.1139/z05-007] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diving behaviour of air-breathing vertebrates may be influenced by a variety of factors including age, body size, and changes in prey behaviour and (or) abundance over both short and long timescales. We studied the diving behaviour of a highly sexually dimorphic odontocete cetacean, the killer whale, Orcinus orca (L., 1758), using suction-cup-attached time-depth recorders (TDRs). We tested the hypotheses that dive rates (no. of dives/h greater than or equal to specific depths) of fish-eating killer whales varied between males and females, with age, between day and night, and among pods and years. Data were used from 34 TDR deployments between 1993 and 2002 in the inshore waters of southern British Columbia, Canada, and Washington, USA. Dive rates did not change with age or differ among pods or between males and females, although analyses restricted to adults showed that adult males dove deep significantly more frequently than adult females during the day. For all whales, dive rates and swim speeds were greater during the day than at night, suggesting decreased activity levels at night. Dive rates to deeper depths during the day decreased over the study, suggesting a long-term change in prey behaviour or abundance, though uncertainty regarding the diet of this population precludes determination of the cause of such changes.
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The impact of lactation strategy on physiological development of juvenile marine mammals: implications for the transition to independent foraging. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.ics.2004.09.032] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
Ducks, fur seals, Weddell seals and probably most cetaceans seem to be able to dive and remain aerobic for durations that are consistent with their elevated stores of usable oxygen and their metabolic rate while diving being similar to that when they are resting at the surface of the water. Ducks, in fact, have a high metabolic rate while diving, mainly because of their large positive buoyancy, but other species have relatively low buoyancy, are better streamlined and use lift-based rather than drag-based propulsion. However, species such as the larger penguins, grey seals and elephant seals seem to achieve the impossible by performing a substantial proportion of their dives for periods longer than would be expected on the above assumptions, and yet remaining aerobic. The logical conclusion is that during such dives these species reduce their metabolic rate below the resting level (hypometabolism) and, in some of them, there is a regional reduction in body temperature (hypothermia) which may contribute to the reduction in metabolic rate.
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Affiliation(s)
- Patrick J Butler
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK.
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MacArthur RA, Weseen GL, Campbell KL. Diving experience and the aerobic dive capacity of muskrats: does training produce a better diver? J Exp Biol 2003; 206:1153-61. [PMID: 12604575 DOI: 10.1242/jeb.00221] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We tested the hypothesis that the body oxygen stores, aerobic dive limit (ADL) and dive performance of muskrats can be enhanced by dive-conditioning in a laboratory setting. We compared several key variables in 12 muskrats trained to swim a 16 m underwater course to a feeding station ('divers') with those of 12 animals precluded from diving but required to travel identical distances in water to feed ('surface swimmers'). Acclimated muskrats assigned to each group were trained concurrently over a 9-11 week period. We observed significant gains in the haematocrit (P=0.0005) and blood haemoglobin concentration (P=0.015) of 'divers', but not 'surface swimmers'. The post-training blood O(2) store calculated for 'divers' (22.9 ml O(2) kg(-1)) was nearly 26% higher than that (18.2 ml O(2) kg(-1)) derived for 'surface swimmers' (P=0.03). Dive-conditioning had no apparent effect on lung volume, whole blood and plasma volumes, nor on the glycogen level and buffering capacity of skeletal muscles. Cardiac and skeletal muscle myoglobin levels were also similar in both test groups following training. The mean total body oxygen store of 'divers' (37.8ml O(2) STPD kg(-1)) was 13.5% higher (P=0.037) than for 'surface swimmers' (33.3 ml O(2) STPD kg(-1)), an increase attributed entirely to the gain in blood O(2) storage capacity of the former group. However, owing to a slightly higher estimate of diving metabolic rate in dive-conditioned animals, the calculated ADL for this group (61.3 s) was indistinguishable from that of 'surface swimmers' (61.8 s). Few differences were observed in the post-training dive behaviour of 'surface swimmers' and 'divers', a finding consistent with the strong similarity in their calculated aerobic dive capacities.
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Affiliation(s)
- Robert A MacArthur
- Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
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McIntyre IW, Campbell KL, MacArthur RA. Body oxygen stores, aerobic dive limits and diving behaviour of the star-nosed mole (Condylura cristata) and comparisons with non-aquatic talpids. J Exp Biol 2002; 205:45-54. [PMID: 11818411 DOI: 10.1242/jeb.205.1.45] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
The dive performance, oxygen storage capacity and partitioning of body oxygen reserves of one of the world’s smallest mammalian divers, the star-nosed mole Condylura cristata, were investigated. On the basis of 722 voluntary dives recorded from 18 captive star-nosed moles, the mean dive duration (9.2±0.2 s; mean ± s.e.m.) and maximum recorded dive time (47 s) of this insectivore were comparable with those of several substantially larger semi-aquatic endotherms. Total body O2 stores of adult star-nosed moles (34.0 ml kg–1) were 16.4 % higher than for similarly sized, strictly fossorial coast moles Scapanus orarius (29.2 ml kg–1), with the greatest differences observed in lung and muscle O2 storage capacity. The mean lung volume of C. cristata (8.09 ml 100 g–1) was 1.81 times the predicted allometric value and exceeded that of coast moles by 65.4 % (P=0.0001). The overall mean myoglobin (Mb) concentration of skeletal muscles of adult star-nosed moles (13.57±0.40 mg g–1 wet tissue, N=7) was 19.5 % higher than for coast moles (11.36±0.34 mg g–1 wet tissue, N=10; P=0.0008) and 54.2 % higher than for American shrew-moles Neurotrichus gibbsii (8.8 mg g–1 wet tissue; N=2). The mean skeletal muscle Mb content of adult star-nosed moles was 91.1 % higher than for juveniles of this species (P<0.0001). On the basis of an average diving metabolic rate of 5.38±0.35 ml O2 g–1 h–1 (N=11), the calculated aerobic dive limit (ADL) of star-nosed moles was 22.8 s for adults and 20.7 s for juveniles. Only 2.9 % of voluntary dives by adult and juvenile star-nosed moles exceeded their respective calculated ADLs, suggesting that star-nosed moles rarely exploit anaerobic metabolism while diving, a conclusion supported by the low buffering capacity of their skeletal muscles. We suggest that a high mass-specific O2 storage capacity and relatively low metabolic cost of submergence are key contributors to the impressive dive performance of these diminutive insectivores.
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Affiliation(s)
- Ian W McIntyre
- Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
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Abstract
SUMMARY
This study investigated physiological and behavioural aspects of diving development in pups of the harbour seal Phoca vitulina. Behavioural data (4280 h, 6027 dives) from time/depth recorders (N=13) deployed on pups aged 0–19 days are presented concomitantly with physiological measurements (N=8, sampled both early and late in the nursing period) of blood oxygen stores and body composition. Pups grew from 12.6±1.8 kg (mean age 2 days, total body fat 16±4 %) to 22.2±2.5 kg (mean age 16 days, total body fat 35±5 %; means ± s.d.) over the duration of the experiment. Pups less than 5 days of age had an elevated haematocrit and reduced plasma volume compared with older pups. Although plasma volume and blood volume increased, mass-specific blood oxygen stores (total haemoglobin) fell during the study period. Simultaneously, the following behavioural indicators of diving ability increased: the proportion of time spent in the water, dive depth, dive duration, bottom time and maximum daily swimming velocity. In addition, the proportion of dives that were identified by cluster analyses as being U-shaped increased significantly with age. On the basis of the measured blood oxygen stores, less than 1 % of the recorded dives exceeded the calculated aerobic dive limit. Thus, development in blood oxygen stores or rates of oxygen consumption did not seem to restrain the rate of neonatal dive development in harbour seals. It appears that behavioural modifications (experience and learning) may be the primary rate-limiting factors for ontogeny of diving skills in neonates of this species.
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Affiliation(s)
- C Jørgensen
- Norwegian Polar Institute, Polar Environmental Center, N-9296 Tromsø, Norway
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47
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Butler PJ. Diving beyond the limits. NEWS IN PHYSIOLOGICAL SCIENCES : AN INTERNATIONAL JOURNAL OF PHYSIOLOGY PRODUCED JOINTLY BY THE INTERNATIONAL UNION OF PHYSIOLOGICAL SCIENCES AND THE AMERICAN PHYSIOLOGICAL SOCIETY 2001; 16:222-7. [PMID: 11572926 DOI: 10.1152/physiologyonline.2001.16.5.222] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Some free-ranging birds and mammals dive for periods that substantially exceed those for which their usable O(2) stores are estimated to last. The mechanisms that extend the duration of aerobic diving include marked reductions in blood flow (and hence O(2) delivery) to certain organs and tissues, passive gliding and, most probably, regional hypothermia.
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Affiliation(s)
- P J Butler
- School of Biosciences, The University of Birmingham, Birmingham B15 2TT, United Kingdom
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48
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MacArthur RA, Humphries MM, Fines GA, Campbell KL. Body oxygen stores, aerobic dive limits, and the diving abilities of juvenile and adult muskrats (Ondatra zibethicus). Physiol Biochem Zool 2001; 74:178-90. [PMID: 11247737 DOI: 10.1086/319662] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2000] [Indexed: 11/04/2022]
Abstract
Intraspecific variability in body oxygen reserves, muscle buffering capacity, diving metabolic rate, and diving behavior were examined in recently captured juvenile and adult muskrats. Allometric scaling exponents for lung (b=1.04), blood (b=0.91), and total body oxygen storage capacity (b=1.09) did not differ from unity. The concentration of skeletal muscle myoglobin scaled positively with mass in 254-600-g juveniles (b=1.63) but was mass-independent in larger individuals. Scaling exponents for diving metabolic rate and calculated aerobic dive limit (ADL) were 0.74 and 0.37, respectively. Contrary to allometric predictions, we found no evidence that the diving abilities of muskrats increased with age or body size. Juveniles aged 1-2 mo exhibited similar dive times but dove more frequently than summer-caught adults. Average and cumulative dive times and dive&rcolon;surface ratios were highest for fall- and winter-caught muskrats. Total body oxygen reserves were greatest in winter, mainly due to an increase in blood oxygen storage capacity. The buffering capacity of the hind limb swimming muscles also was highest in winter-caught animals. Several behavioral indicators of dive performance, including average and maximum duration of voluntary dives, varied positively with blood hemoglobin and muscle myoglobin concentration of muskrats. However, none of the behavioral measures were strongly correlated with the total body oxygen reserves or ADLs derived for these same individuals.
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Affiliation(s)
- R A MacArthur
- Department of Zoology, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
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49
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Ponganis PJ, Kooyman GL. Diving physiology of birds: a history of studies on polar species. Comp Biochem Physiol A Mol Integr Physiol 2000; 126:143-51. [PMID: 10936756 DOI: 10.1016/s1095-6433(00)00208-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Our knowledge of avian diving physiology has been based primarily on research with polar species. Since Scholander's 1940 monograph, research has expanded from examination of the 'diving reflex' to studies of free-diving birds, and has included laboratory investigations of oxygen stores, muscle adaptations, pressure effects, and cardiovascular/metabolic responses to swimming exercise. Behavioral and energetic studies at sea have shown that common diving durations of many avian species exceed the calculated aerobic diving limits (ADL). Current physiological research is focused on factors, such as heart rate and temperature, which potentially affect the diving metabolic rate and duration of aerobic diving.
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Affiliation(s)
- P J Ponganis
- Center for Marine Biotechnology/Biomedicine, Scripps Institution of Oceanography, University of California San Diego, 92093-0204, La Jolla, CA, USA.
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