Skip to main content
Springer Nature Link
Log in

Examining the potential for nutritional stress in young Steller sea lions: physiological effects of prey composition

  • Original Paper
  • Published:
Journal of Comparative Physiology B Aims and scope Submit manuscript

Abstract

The effects of high- and low-lipid prey on the body mass, body condition, and metabolic rates of young captive Steller sea lions (Eumetopias jubatus) were examined to better understand how changes in prey composition might impact the physiology and health of wild sea lions and contribute to their population decline. Results of three feeding experiments suggest that prey lipid content did not significantly affect body mass or relative body condition (lipid mass as a percent of total mass) when sea lions could consume sufficient prey to meet their energy needs. However, when energy intake was insufficient to meet daily requirements, sea lions lost more lipid mass (9.16±1.80 kg±SE) consuming low-lipid prey compared with eating high-lipid prey (6.52±1.65 kg). Similarly, the sea lions lost 2.7±0.9 kg of lipid mass while consuming oil-supplemented pollock at maintenance energy levels but gained 5.2±2.7 kg lipid mass while consuming identical energetic levels of herring. Contrary to expectations, there was a 9.7±1.8% increase in metabolism during mass loss on submaintenance diets. Relative body condition decreased only 3.7±3.8% during periods of imposed nutritional stress, despite a 10.4±4.8% decrease in body mass. These findings raise questions regarding the efficacy of measures of relative body condition to detect such changes in nutritional status among wild animals. The results of these three experiments suggest that prey composition can have additional effects on sea lion energy stores beyond the direct effects of insufficient energy intake.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  • Ainley DG, Sydeman WJ, Norton J (1995) Upper trophic level predators indicate interannual negative and positive anomalies in the California Current food web. Mar Ecol Prog Ser 118:69–79

    Google Scholar 

  • Alverson DL (1992) Commercial fisheries and the Steller sea lion (Eumetopias jubatus): the conflict arena. Rev Aquat Sci 6:203–256

    Google Scholar 

  • Anthony JA, Roby DD, Turco KR (2000) Lipid content and energy density of forage fishes from the northern Gulf of Alaska. J Exp Mar Biol Ecol 248:53–78

    Google Scholar 

  • Arnould JPY, Boyd IL, Speakman JR (1996) Measuring the body composition of Antarctic fur seals (Arctocephalus gazella): validation of hydrogen isotope dilution. Physiol Zool 69:93–116

    Google Scholar 

  • Barrett RT (1996) Prey harvest, chick growth, and production of three seabird species in Bleiksoy, North Norway, during years of variable food availability. Can Wildl Serv Occas Pap No 91:20–26

    Google Scholar 

  • Bowen WD, Iverson SJ (1998) Estimation of total body water in pinnipeds using hydrogen-isotope dilution. Physiol Zool 71:329–332

    Google Scholar 

  • Bryant R, Jones IL, Hipfner JM (1999) Responses to changes in food availability by Common Murres and Thick-billed Murres at the Gannet Islands, Labrador. Can J Zool 77:1278–1287

    Google Scholar 

  • Castellini MA (2002) Captive studies with Steller sea lions at the Alaska SeaLife Center. In: DeMaster D, Atkinson S (eds) Steller sea lion decline: is it food II? Alaska Sea Grant, AK-SG-02–02, Fairbanks, p 80

  • Cherel Y, Heitz A, Calgari C, Robin J-P, Le Maho Y (1992) Relationships between lipid availability and protein utilization during prolonged fasting. J Comp Physiol B 162:305–313

    Google Scholar 

  • Donnelly CP, Trites AW, Kitts DD (2003) Possible effects of pollock and herring on the growth and reproductive success of Steller sea lions (Eumetopias jubatus): insights from feeding experiments using an alternative animal model, Rattus norvegicus. Brit J Nutr 89:71–82

    Google Scholar 

  • Kirsch PE, Iverson SJ, Bowen WD (2000) Effect of a low-fat diet on body composition and blubber fatty acids of captive juvenile harp seals (Phoca groenlandica). Physiol Biochem Zool 73:45–59

    Google Scholar 

  • Kitaysky AS, Piatt JF, Wingfield JC, Romano M (1999) The adrenocortical stress-response of Black-legged Kittiwake chicks in relation to dietary restrictions. J Comp Physiol B 169:303–310

    Google Scholar 

  • Kleiber M (1975) The fire of life: an introduction to animal energetics. Robert E. Krieger, New York

    Google Scholar 

  • Litzow MA, Piatt JF, Prichard AK, Roby DD (2002) Response of pigeon guillemots to variable abundance of high-lipid and low-lipid prey. Oecologia 132:286–295

    Google Scholar 

  • Merrick RL, Calkins DG (1996) Importance of juvenile walleye pollock, Theragra chalcogramma, in the diet of Gulf of Alaska Steller sea lions, Eumetopias jubatus. NOAA technical report (NMFS) No. 126

  • Merrick RL, Chumbley MK, Byrd GV (1997) Diet diversity of Steller sea lions (Eumetopias jubatus) and their population decline in Alaska: a potential relationship. Can J Fish Aquat Sci 54:1342–1348

    Google Scholar 

  • Øritsland NA (1990) Starvation survival and body composition in mammals with particular reference to Homo sapiens. Bull Math Biol 52:643–655

    Google Scholar 

  • Payne SA, Johnson BA, Otto RS (1999) Proximate composition of some north-eastern Pacific forage fish species. Fish Oceanogr 8:159–177

    Google Scholar 

  • Rea LD, Castellini MA, Fadely BS, Loughlin TR (1998) Health status of young Alaska Steller sea lion pups (Eumetopias jubatus) as indicated by blood chemistry and hematology. Comp Biochem Physiol A 120:617–623

    Google Scholar 

  • Rea LD, Rosen DAS, Trites AW (2000) Metabolic response to fasting in 6-week-old Steller sea lion pups (Eumetopias jubatus). Can J Zool 78:890–894

    Google Scholar 

  • Reilly JJ, Fedak MA (1990) Measurement of the body composition of living gray seals by hydrogen isotope dilution. J Appl Physiol 69:885–891

    Google Scholar 

  • Rosen DAS, Trites AW (1997) Heat increment of feeding in Steller sea lions, Eumetopias jubatus. Comp Biochem Physiol 118A:877–881

    Google Scholar 

  • Rosen DAS, Trites AW (1999) Metabolic effects of low-energy diet on Steller sea lions, Eumetopias jubatus. Physiol Biochem Zool 72:723–731

    Google Scholar 

  • Rosen DAS, Trites AW (2002) Changes in metabolism in response to fasting and food restriction in the Steller sea lion. Comp Biochem Physiol B 132:389–399

    Google Scholar 

  • Rosen DAS, Trites AW (2004) Satiation and compensation for short-term changes in food quality and availability in young Steller sea lions (Eumetopias jubatus). Can J Zool 82:1061–1069

    Google Scholar 

  • Rosen DAS, Hastie GD, Trites AW (2004) Searching for stress: hematological indicators of nutritional inadequacies in Steller sea lions. In: Symposia of the Comparative nutrition society, Hickory Corners, Michigan, pp 145–149

  • Shettleworth SJ (1989) Animals foraging in the lab: problems and promises. J Exp Psych 15:81–87

    Google Scholar 

  • Sinclair EH, Zeppelin TK (2002) Seasonal and spatial differences in diet in the western stock of Steller sea lions (Eumetopias jubatus). J Mammal 83:973–990

    Google Scholar 

  • Speakman JR, Visser GH, Ward S, Krol E (2001) The isotope dilution method for the evaluation of body composition. In: Speakman JR (ed) Body composition analysis of animals; A handbook of non-destructive methods. Cambridge University Press, London, pp 56–98

    Google Scholar 

  • Stanberry K (2003) The effect of changes in dietary fat level on body composition, blood metabolites and hormones, rate of passage, and nutrient assimilation efficiency in harbor seals. MSc thesis, Animal Sciences, University of Hawaii

  • Trites AW, Donnelly CP (2003) The decline of Steller sea lions in Alaska: a review of the nutritional stress hypothesis. Mammal Rev 33:3–28

    Google Scholar 

  • Trumble SJ, Barboza PS, Castellini MA (2003) Digestive constraints on an aquatic carnivore: effects of feeding frequency and prey composition on harbor seals. J Comp Physiol B 173:501–509

    Google Scholar 

  • Wespestad VG, Fritz LW, Ingraham WJ, Megrey BA (2000) On relationships between cannibalism, climate variability, physical transport, and recruitment success of Bering Sea walleye pollock (Theragra chalcogramma). ICES J Mar Sci 57:272–278

    Google Scholar 

  • Wilson PN, Osbourn DF (1960) Compensatory growth after undernutrition in mammals and birds. Biol Rev 35:324–363

    Google Scholar 

  • Winship AJ, Trites AW (2003) Prey consumption of Steller sea lions (Eumetopias jubatus) off Alaska: how much prey do they require? Fish Bull US 101:147–163

    Google Scholar 

  • York AE (1994) The population dynamics of Northern sea lions, 1975–1985. Mar Mamm Sci 10:38–51

    Google Scholar 

  • Zar JH (1996) Biostatistical analysis, 3rd edn. Prentice-Hall, Englewood Cliffs, p 662

    Google Scholar 

  • Zurovchak JG, Stiles EW, Place AR (1999) Effect of dietary lipid level on lipid passage rate and lipid absorption efficiency in American robins (Turdus migratorius). J exp Biol 283:408–417

    Google Scholar 

Download references

Acknowledgements

We are grateful to the training staff of the Marine Mammal Department, Vancouver Aquarium Marine Science Centre for their role in handling and training the sea lions, and to Rebecca Barrick and Chad Nordstrom for data collection and experimental logistics. Arliss Winship provided useful comments on an earlier draft, and Ruth Joy assisted with the statistical analyses. We would like to thank two anonymous reviewers for their suggestions to improve the paper. Financial support was provided by a grant from the North Pacific Marine Science Foundation to the North Pacific Universities Marine Mammal Research Consortium, with additional support from the U.S. National Oceanic and Atmospheric Administration.

Author information

Authors and Affiliations

  1. Marine Mammal Research Unit, University of British Columbia, 6248 Biological Sciences Road, Vancouver, BC, Canada, V6T 1Z4

    David A. S. Rosen & Andrew W Trites

Authors
  1. David A. S. Rosen
    View author publications

    You can also search for this author inPubMed Google Scholar

  2. Andrew W Trites
    View author publications

    You can also search for this author inPubMed Google Scholar

Corresponding author

Correspondence to David A. S. Rosen.

Additional information

Communicated by I.D. Hume

Rights and permissions

Reprints and permissions

About this article

Cite this article

Rosen, D.A.S., Trites, A.W. Examining the potential for nutritional stress in young Steller sea lions: physiological effects of prey composition. J Comp Physiol B 175, 265–273 (2005). https://doi.org/10.1007/s00360-005-0481-5

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00360-005-0481-5

Keywords