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. 2014 Jan 22;9(1):e86208.
doi: 10.1371/journal.pone.0086208. eCollection 2014.

Interspecific aggression and habitat partitioning in garter snakes

Michael Edgehouse  1 , Leigh C Latta 4th  2 , Edmund D Brodie 3rd  3 , Edmund D Brodie Jr  4
Affiliations

Interspecific aggression and habitat partitioning in garter snakes

Michael Edgehouse et al. PLoS One. .

Abstract

Defense of a limited resource, such as space or food, has recently been discovered in snakes and has been widely documented in lizards. Garter snakes (Thamnophis spp.) are historically considered generalist predators such that food is not a limiting resource. However, in this study we show that the common garter snake (Thamnophis sirtalis) and the aquatic garter snake (Thamnophis atratus) show a strong preference for amphibians as their primary food source at the Santa Lucia Preserve (SLP), Monterey County, California. This food preference forces these snake species at SLP to exploit aquatic habitats. Our principle goal was to investigate the aggressive behavior of T. sirtalis and the potential that this aggression displaces T. atratus from its preferred habitat. We found that when individuals from either species are alone, a 100% preference for aquatic or near aquatic habitat is observed. In contrast, when these species are together, T. sirtalis occupy the aquatic habitat and T. atratus occupy an area far removed from water. Thamnophis sirtalis often physically force T. atratus from the aquatic habitat through repeated biting and other displays of aggression.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Behavior test chamber diagram.
Enclosures were 4- meter delineations, by 1 meter wide, by .45 meters high. Each 1-meter zone was assigned numbers 1, 2, 3, or 4. Zone 1 was farthest from water and contained one 30 cm×30 cm×1 cm Styrofoam cover object (indicated by an asterisk), zone 4 was in the water. Snakes were introduced into the enclosures in zone 1.
Figure 2
Figure 2. Median positions of Thamnophis atratus (TA) and Thamnophis sirtalis (TS) when alone in the enclosures at SLP.
Abbreviations are the same as in figures 2 and 3.
Figure 3
Figure 3. Median positions of Thamnophis atratus (TA) and Thamnophis sirtalis (TS) in enclosures for the SLP locality.
The focal species before (filled circles and solid lines) and after (open circles and solid lines) the addition of the second species (squares and dashed lines) are indicated in each panel. A) The response of T. atratus to the addition of T. sirtalis. B) The response of T. sirtalis to the addition of T. atratus. Only T. atratus showed a significant change in position in response to the addition of T. sirtalis.
Figure 4
Figure 4. Mean number of prey (±2 SE) for Thamnophis atratus (TA) and Thamnophis sirtalis (TS) consumed by individuals at SLP.
See this image and copyright information in PMC

References

    1. Maynard-Smith J (1982) Evolution and the Theory of Games. Cambridge: Cambridge University Press.
    1. Pinter-Wollman N, Dayan T, Eilam D, Kronfeld-Schor N (2006) Can aggression be the force driving temporal separation between competing common and golden spiny mice. J Mammal 87: 48–53.
    1. Lancaster DL, Jaeger RG (1995) Rules of engagement for adult salamanders in territorial conflicts with heterospecific juveniles. Behav Ecol Sociobiol 37: 25–29.
    1. Smyers SD, Rubbo MJ, Townsend VR Jr, Stewart CC (2002) Intra- and interspecific characterizations of burrow use and defense by juvenile ambystomatid salamanders. Herpetologica 58: 422–429.
    1. Griffis MR, Jaeger RG (1998) Competition leads to an extinction-prone species of salamander: Interspecific territoriality in a metapopulation. Ecology 79: 2494–2502.

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