Sex-specific hoarding behavior in North American red squirrels (Tamiasciurus hudsonicus)

Devan W. Archibald, Quinn E. Fletcher, Stan Boutin, Andrew G. McAdam, John R. Speakman, Murray M. Humphries*

*Corresponding author for this work

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In short-term hoarding rodents, reproduction and hoarding often overlap and reproductive status can alter hoarding behavior. In long-term hoarders these activities are often separated seasonally. Therefore, annual and sex-specific variation in the timing of reproduction relative to the hoarding season may influence variation in the hoarding behavior of long-term hoarders. North American red squirrels (Tamiasciurus hudsonicus) clip and hoard white spruce (Picea glauca) cones each autumn, but have variation in reproductive timing such that in some years the hoarding season overlaps with reproductive activity. Over 4 years with naturally varying cone availability we quantified reproductive timing and hoarding behavior. Males completed mating 22-90 days before the onset of hoarding, whereas large numbers (45-86%) of females during large cone crop years weaned litters after hoarding commenced. Despite these differences in reproductive timing, across all years females clipped more cones than did males, whereas males hoarded more cones and had a higher propensity to larder-hoard than did females. Interestingly, in the years with large cone crops, females that weaned their litters later (during the hoarding season) did not have reduced hoarding or reproductive performance (offspring growth and recruitment) than females that weaned their litters earlier. In the year with the most extensive overlap between female reproduction and hoarding, lactating females did not differ from males in the amount of time they allocated to hoarding. In this year, the daily energy expenditure of lactating females during the hoarding season did not differ from that of males engaged in hoarding or from that of lactating females prior to the hoarding season. Hence, under high-resource conditions the competing demands of lactation and hoarding can both be sustained, allowing red squirrels flexibility in the separation between reproduction and hoarding.

Original languageEnglish
Pages (from-to)761-770
Number of pages10
JournalJournal of Mammalogy
Volume94
Issue number4
DOIs
Publication statusPublished - 16 Aug 2013

Fingerprint

Tamiasciurus hudsonicus
Sciuridae
caching
seed cones
squirrels
lactating females
gender
litters (young animals)
Picea glauca
crop year
Reproduction
energy expenditure
Hoarding
reproductive performance
litter
rodents
lactation
autumn
crops
reproductive status

Keywords

  • behavior
  • energetics
  • intraspecific variation
  • lactation
  • larder-hoarding
  • scatter-hoarding

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Animal Science and Zoology
  • Genetics
  • Nature and Landscape Conservation

Cite this

Sex-specific hoarding behavior in North American red squirrels (Tamiasciurus hudsonicus). / Archibald, Devan W.; Fletcher, Quinn E.; Boutin, Stan; McAdam, Andrew G.; Speakman, John R.; Humphries, Murray M.

In: Journal of Mammalogy, Vol. 94, No. 4, 16.08.2013, p. 761-770.

Research output: Contribution to journalArticle

Archibald, DW, Fletcher, QE, Boutin, S, McAdam, AG, Speakman, JR & Humphries, MM 2013, 'Sex-specific hoarding behavior in North American red squirrels (Tamiasciurus hudsonicus)', Journal of Mammalogy, vol. 94, no. 4, pp. 761-770. https://doi.org/10.1644/12-MAMM-A-213.1
Archibald, Devan W. ; Fletcher, Quinn E. ; Boutin, Stan ; McAdam, Andrew G. ; Speakman, John R. ; Humphries, Murray M. / Sex-specific hoarding behavior in North American red squirrels (Tamiasciurus hudsonicus). In: Journal of Mammalogy. 2013 ; Vol. 94, No. 4. pp. 761-770.
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note = "Acknowledgments We thank our field assistants and volunteers for their aid in data collection and G. Larocque for his aid in modeling cone clipping and hoarding rates. Research support was provided by the Natural Sciences and Engineering Council of Canada, the Northern Scientific Training Program, the Ontario Ministry of Research and Innovation, and the National Science Foundation. A Natural Sciences and Engineering Council of Canada Postgraduate Graduate Scholarship provided personal support to DWA. This is paper 68 of the Kluane Red Squirrel Project.",
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