Skip to main content
SpringerLink
Log in

Fat and fed: frequent use of summer torpor in a subtropical bat

  • ORIGINAL PAPER
  • Published:
Naturwissenschaften Aims and scope Submit manuscript

Abstract

A widely held view is that torpor is avoided by mammals whenever possible because of potential costs associated with reduced body temperatures and slowed metabolic processes. We examined this hypothesis by quantifying use of torpor in relation to body condition of free-ranging northern long-eared bats (Nyctophilus bifax, approximately 10 g), a species known to hibernate, from a subtropical region during the austral summer when insects were abundant. Temperature-telemetry revealed that bats used torpor on 85% of observation days and on 38% of all nights. Torpor bouts ranged from 0.7 to 21.2 h, but the relationship between duration of torpor bouts and ambient temperature was not significant. However, skin temperature of torpid bats was positively correlated with ambient temperature. Against predictions, individuals with a high body condition index (i.e., good fat/energy reserves) expressed longer and deeper torpor bouts and also employed torpor more often during the activity phase at night than those with low body condition index. We provide the first evidence that use of torpor in a free-ranging subtropical mammal is positively related with high body condition index. This suggests that employment of torpor is maximised and foraging minimised not because of food shortages or low energy stores but likely to avoid predation when bats are not required to feed.

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

Access this article

Log in via an institution

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

Similar content being viewed by others

Abbreviations

MR:

Metabolic rate

Ta :

Ambient temperature

Tb :

Body temperature

Tskin :

Skin temperature

BCI:

Body condition index

References

  • Abrahams MV, Dill LM (1989) A determination of the energetic equivalence of the risk of predation. Ecology 70:999–1007

    Article  Google Scholar 

  • Arendt T, Stieler J, Strijkstra AM, Hut RA, Rüdiger J, Van der Zee EA, Harkany T, Holzer M, Härtig W (2003) Reversible paired helical filament-like phosphorylation of tau is an adaptive process associated with neuronal plasticity in hibernating animals. J Neurosci 23:6972–6981

    CAS  PubMed  Google Scholar 

  • Arlettaz R, Ruchet C, Aeschimann J, Brun E, Genoud M, Vogel P (2000) Physiological traits affecting the distribution and wintering strategy of the bat Tadarida teniotis. Ecology 81:1004–1014

    Google Scholar 

  • Barclay RMR, Harder LD (2003) Life histories of bats: life in the slow lane. In: Kunz TH, Fenton MB (eds) Bat ecology. University of Chicago Press, Chicago, pp 209–253

    Google Scholar 

  • Barclay RMR, Kalcounis MC, Crampton LH, Stefan C, Vonhof MJ, Wilkinson L, Brigham RM (1996) Can external radiotransmitters be used to assess body temperature and torpor in bats? J Mammal 77:1102–1106

    Article  Google Scholar 

  • Barclay RMR, Lausen CL, Hollis L (2001) What’s hot and what’s not: defining torpor in free-ranging birds and mammals. Can J Zool 79:1885–1890

    Article  Google Scholar 

  • Bieber C, Ruf T (2009) Summer dormancy in edible dormice (Glis glis) without energetic constraints. Naturwissenschaften 96:165–171

    Article  CAS  PubMed  Google Scholar 

  • Boyles JG, Dunbar MB, Storm JJ, Brack VJ (2007) Energy availability influences microclimate selection of hibernating bats. J Exp Biol 210:4345–4350

    Article  PubMed  Google Scholar 

  • Brigham RM, Körtner G, Maddocks TA, Geiser F (2000) Seasonal use of torpor by free-ranging Australian owlet-nightjars (Aegotheles cristatus). Physiol Biochem Zool 73:613–620

    Article  CAS  PubMed  Google Scholar 

  • Bronner GN, Maloney SK, Buffenstein R (1999) Survival tactics within thermally-challenging roosts: heat tolerance and cold sensitivity in the Angolan free-tailed bat, Mops condylurus. S Afr J Zool 34:1–10

    Google Scholar 

  • Buck CL, Barnes BM (2000) Effects of ambient temperature on metabolic rate, respiratory quotient, and torpor in an arctic hibernator. Am J Physiol Regul Integr Comp Physiol 279:R255–R262

    CAS  PubMed  Google Scholar 

  • Christian N, Geiser F (2007) To use or not to use torpor? Activity and body temperature as predictors. Naturwissenschaften 94:483–487

    Article  CAS  PubMed  Google Scholar 

  • Churchill S (1998) Australian bats. New Holland Publishers (Australia) Pty Ltd, Sydney

    Google Scholar 

  • Dausmann KH (2008) Hypometabolism in primates: torpor and hibernation. In: Lovegrove BG, McKechnie AE (eds) Hypometabolism in animals: hibernation, torpor and cryobiology. University of KwaZulu-Natal, Pietermaritzburg South Africa, pp 327–336

    Google Scholar 

  • Frank CL (1994) Polyunsaturate content and diet selection by ground squirrels (Spermophilus lateralis). Ecology 75:458–463

    Article  Google Scholar 

  • French AR (1976) Selection of high temperatures for hibernation by the pocket mouse, Perognathus longimembris: ecological advantages and energetic consequences. Ecology 57:185–191

    Article  Google Scholar 

  • Geiser F (2004) Metabolic rate and body temperature reduction during hibernation and daily torpor. Annu Rev Physiol 66:239–274

    Article  CAS  PubMed  Google Scholar 

  • Geiser F, Brigham RM (2000) Torpor, thermal biology, and energetics in Australian long-eared bats (Nyctophilus). J Comp Physiol B 170:153–162

    Article  CAS  PubMed  Google Scholar 

  • Geiser F, Kenagy GJ (1990) Development of thermoregulation and torpor in the golden-mantled ground squirrel Spermophilus saturatus. J Mammal 71:286–290

    Article  Google Scholar 

  • Geiser F, Turbill C (2009) Hibernation and daily torpor minimize mammalian extinctions. Naturwissenschaften. doi:10.1007/s00114-009-0583-0

    Google Scholar 

  • Humphries MM, Thomas DW, Kramer DL (2003) The role of energy availability in mammalian hibernation: a cost-benefit approach. Physiol Biochem Zool 76:165–179

    Article  PubMed  Google Scholar 

  • Körtner G, Geiser F (2000) Torpor and activity patterns in free-ranging sugar gliders Petaurus breviceps (Marsupialia). Oecologia 123:350–357

    Article  Google Scholar 

  • Körtner G, Geiser F (2009) The key to winter survival: daily torpor in a small arid-zone marsupial. Naturwissenschaften 96:525–530

    Article  PubMed  CAS  Google Scholar 

  • Landry-Cuerrier M, Munro D, Thomas DW, Humphries MM (2008) Climate and resource determinants of fundamental and realized metabolic niches of hibernating chipmunks. Ecology 89:3306–3316

    Article  CAS  PubMed  Google Scholar 

  • Luis AD, Hudson PJ (2006) Hibernation patterns in mammals: a role for bacterial growth? Funct Ecol 20:471–477

    Article  Google Scholar 

  • O’Shea TJ, Vaughan TA (1977) Nocturnal and seasonal activities of the Pallid bat, Antrozous pallidus. J Mammal 58:269–284

    Article  Google Scholar 

  • Park KJ, Jones G, Ransome RD (2000) Torpor, arousal and activity of hibernating Greater Horseshoe Bats (Rhinolophus ferrumequinum). Funct Ecol 14:580–588

    Article  Google Scholar 

  • Prendergast BJ, Freeman DA, Zucker I, Nelson JR (2002) Periodic arousal from hibernation is necessary for initiation of immune response in ground squirrels. Am J Physiol Regul Integr Comp Physiol 282:R1054–R1062

    CAS  PubMed  Google Scholar 

  • Rambaldini DA, Brigham RM (2008) Torpor use by free-ranging pallid bats (Antrozous pallidus) at the northern extent of their range. J Mammal 89:933–941

    Article  Google Scholar 

  • Schmid J, Ganzhorn JU (2009) Optional strategies for reduced metabolism in gray mouse lemurs. Naturwissenschaften 96:737–741

    Article  CAS  PubMed  Google Scholar 

  • Sendor T, Simon M (2003) Population dynamics of the pipistrelle bat: effects of sex, age and winter weather on seasonal survival. J Anim Ecol 72:308–320

    Article  Google Scholar 

  • Song X, Geiser F (1997) Daily torpor and energy expenditure in Sminthopsis macroura: interactions between food and water availability and temperature. Physiol Zool 70:331–337

    CAS  PubMed  Google Scholar 

  • Speakman JR, Racey PA (1986) The influence of body condition on sexual development of male brown long-eared bats (Plecotus auritus) in the wild. J Zool 210:515–525

    Google Scholar 

  • Stawski C, Turbill C, Geiser F (2009) Hibernation by a free-ranging subtropical bat (Nyctophilus bifax). J Comp Physiol B 179:433–441

    Article  PubMed  Google Scholar 

  • Taylor LR (1963) Analysis of the effect of temperature on insects in flight. J Anim Ecol 32:99–117

    Article  Google Scholar 

  • Taylor RJ, O’Neill MG (1988) Summer activity patterns of insectivorous bats and their prey in Tasmania. Aust Wildl Res 15:533–539

    Article  Google Scholar 

  • Turbill C (2008) Winter activity of Australian tree-roosting bats: influence of temperature and climatic patterns. J Zool 276:285–290

    Article  Google Scholar 

  • Turbill C, Körtner G, Geiser F (2003a) Natural use of heterothermy by a small, tree-roosting bat during summer. Physiol Biochem Zool 76:868–876

    Article  PubMed  Google Scholar 

  • Turbill C, Law BS, Geiser F (2003b) Summer torpor in a free-ranging bat from subtropical Australia. J Therm Biol 28:223–226

    Article  Google Scholar 

  • Twente JW, Twente JA (1965) Regulation of hibernating periods by temperature. Proc Natl Acad Sci USA 54:1058–1061

    Article  CAS  PubMed  Google Scholar 

  • Vivier L, Van Der Merwe M (2007) The incidence of torpor in winter and summer in the Angolan free-tailed bat, Mops condylurus (Microchiroptera: Molossidae), in a subtropical environment, Mpumulanga, South Africa. Afr Zool 42:50–58

    Article  Google Scholar 

  • Warnecke L, Turner JM, Geiser F (2008) Torpor and basking in a small arid zone marsupial. Naturwissenschaften 95:73–78

    Article  CAS  PubMed  Google Scholar 

  • Wilkinson GS, South JM (2002) Life history, ecology and longevity of bats. Aging Cell 1:124–131

    Article  CAS  PubMed  Google Scholar 

  • Willis CKR, Turbill C, Geiser F (2005) Torpor and thermal energetics in a tiny Australian vespertillonid, the little forest bat (Vespadelus vulturnus). J Comp Physiol B 175:479–486

    Article  PubMed  Google Scholar 

Download references

Acknowledgments

We would like to thank Margaret Stawski for all her help with fieldwork. We are also grateful to Gerhard Körtner, Brad Law, Alexander Riek, Michal Stawski, Christopher Turbill, and Courtney Waugh for their contributions to this study. This research was undertaken in agreement with permits issued by New South Wales National Parks and Wildlife Service and the Animal Ethics Committee of the University of New England. The study was supported by grants from the University of New England and Bat Conservation International to CS and the Australian Research Council to FG.

Author information

Authors and Affiliations

  1. Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale, NSW, 2351, Australia

    Clare Stawski & Fritz Geiser

Authors
  1. Clare Stawski
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Fritz Geiser
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Clare Stawski.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Stawski, C., Geiser, F. Fat and fed: frequent use of summer torpor in a subtropical bat. Naturwissenschaften 97, 29–35 (2010). https://doi.org/10.1007/s00114-009-0606-x

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00114-009-0606-x

Keywords

Search

Navigation