Spacing Behavior of a Non-Larder-Hoarding Tamiasciurus

A Study of Mearns's Squirrels in Xeric Coniferous Forests

Nicolás Ramos-Lara, John Koprowski

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

In ecosystems with seasonal fluctuations in food supply many species use two strategies to store food: larder hoarding and scatter hoarding. However, because species at different geographic locations may experience distinct environmental conditions, differences in hoarding behavior may occur. Tree squirrels in the genus Tamiasciurus display variation in hoarding behavior. Whereas red (Tamiasciurus hudsonicus) and Douglas's (Tamiasciurus douglasii) squirrels in mesic coniferous forests defend territories centered around larder hoards maintaining non-overlapping home ranges, red squirrels in deciduous forests defend small scatter-hoarded caches of cones maintaining overlapping home ranges. As in other rodent species, variation in hoarding behavior appears to influence the spacing behavior of red and Douglas's squirrels. In contrast, Mearns's squirrels (Tamiasciurus mearnsi) in xeric coniferous forests neither rely on larder hoards nor appear to display territorial behavior. Unfortunately, little is known about the ecology of this southernmost Tamiasciurus. Using radiotelemetry, we estimated home-range size, overlap, and maximum distance traveled from nest to examine the spacing behavior of Mearns's squirrels. Similar to scatter-hoarding rodents, maximum distance traveled from nest was greater for males during mating season, whereas those of females were similar year round. Although no seasonal differences were detected, male home ranges were three times larger during mating season, whereas those of females were smaller and displayed a minor variation between seasons. Home ranges were overlapped year round but contrary to our expectations, overlap was greater during mating season for both sexes, with no detectable relationship between male home-range size and the number of females overlapped during mating season. Overall, the results appear to support our hypothesis that in the absence of larder hoards, the spacing behavior of Mearns's squirrels should be different from larder-hoarding congeners and more similar to scatter-hoarding rodents.

Original languageEnglish (US)
Pages (from-to)196-205
Number of pages10
JournalEthology
Volume121
Issue number2
DOIs
StatePublished - Feb 1 2015

Fingerprint

Tamiasciurus
caching
squirrels
coniferous forest
coniferous forests
spacing
home range
spatial distribution
breeding season
rodent
rodents
range size
nests
nest
Tamiasciurus hudsonicus
food storage
radio telemetry
radiotelemetry
deciduous forests
food supply

Keywords

  • Tamiasciurus mearnsi
  • Baja California
  • Hoarding behavior
  • Mating system
  • Radio-telemetry
  • Spacing behavior

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Ecology, Evolution, Behavior and Systematics

Cite this

Spacing Behavior of a Non-Larder-Hoarding Tamiasciurus : A Study of Mearns's Squirrels in Xeric Coniferous Forests. / Ramos-Lara, Nicolás; Koprowski, John.

In: Ethology, Vol. 121, No. 2, 01.02.2015, p. 196-205.

Research output: Contribution to journalArticle

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