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Updated: Jun 3, 2026
10:20
Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
Native herbivore exerts contrasting effects on fire regime and vegetation structure
José L Hierro1, Kenneth L Clark, Lyn C Branch
1Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Pampa, Argentina. jhierro@conicet.gov.ar
Oecologia
|March 9, 2011
Summary
Native vizcachas (Lagostomus maximus) influence fire intensity in Argentina
Area of Science:
- Ecology
- Fire Ecology
- Herbivore-Plant Interactions
Background:
- Native herbivores impact fire regimes by altering fuel availability and structure.
- Contrasting effects of herbivores on fire regimes are not well understood.
- Vizcachas (Lagostomus maximus) are colonial rodents inhabiting semiarid scrub ecosystems.
Purpose of the Study:
- To investigate the dual role of vizcachas in modulating fire intensity.
- To test hypotheses on how active and abandoned vizcacha colonies affect fire behavior.
Main Methods:
- Assessed shrub (Larrea divaricata) stem age and aboveground biomass in grazed and ungrazed areas.
- Compared live and dead shrub densities on burned abandoned colonies and adjacent zones.
- Analyzed vizcacha population cycle stages in relation to fire intensity.
Main Results:
- Active vizcacha colonies exhibited greater shrub age and biomass due to intense grazing, creating firebreaks.
- Abandoned colonies showed increased fire intensity, leading to higher shrub mortality.
- Vizcachas augment fire intensity by accumulating coarse wood fuel on colonies.
Conclusions:
- Vizcachas exhibit opposing effects on fire intensity, reducing it during active colony phases and increasing it during abandonment.
- Herbivore-mediated fuel accumulation significantly impacts fire behavior in semiarid ecosystems.
- Native herbivores enhance vegetation heterogeneity in woody-dominated landscapes through fire interactions.
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