Fire‐mediated niche‐separation between two sympatric small mammal species. (12th July 2014)

• Record Type: Journal Article
• Authors: Mowat, Emily J.; Webb, Jonathan K.; Crowther, Mathew S.
• Is Part Of: Austral ecology. Volume 40:Number 1(2015)
• Page Start: 50
• Page End: 59
• Publication Date: 2014-07-12
• Subjects: Ecology -- Southern Hemisphere -- Periodicals; Ecology -- Australia -- Periodicals; 557
• DOI: 10.1111/aec.12166
• Languages: English
• ISSNs: 1442-9985

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Fire is a key ecological process influencing the population dynamics of small mammals. Whilst shifting competitive advantage amongst small mammal species following a single fire event is well‐documented, there has been little investigation of the potential influence of fire frequency on small mammal interspecific interactions. In this study, we investigated the effect of fire frequency on the abundance of two small dasyurid mammals, <italic>A</italic><italic>ntechinus stuartii</italic> and <italic>A</italic><italic>. flavipes</italic>, which occur sympatrically in some parts of their range. The two antechinus species are known to have different habitat preferences, so it is possible that fire regimes may promote their coexistence in areas of sympatry by altering vegetation structure. To investigate this possibility, we estimated the abundance of both species using replicate sites which differed in the number of times burnt (1–4) during the last four decades, but with identical time‐since‐fire. Proportionally, we captured greater numbers of <italic>A</italic><italic>. stuartii</italic> in less frequently burnt sites and greater numbers of <italic>A</italic><italic>. flavipes</italic> in more‐frequently burnt sites. Hence, fire may mediate niche‐separation between these two species. To clarify further this pattern of response to fire frequency, we investigated which structural habitat variables differed between fire frequencies, and compared antechinus abundances with structural vegetation characteristics. We found a trend for lower ground cover density under higher fire frequencies. This offers one potential explanation of the patterns of abundance that we observed. Our study provided insights into the complexities of small mammal responses to fire, and strongly suggests that fire could mediate competitive interactions between species.</p> </abstract>