Aim: To describe the nexus between Aboriginal landscape burning and patterns of habitat use by kangaroos in a tropical savanna habitat mosaic, and to provide evidence to evaluate the claim that Aboriginal landscape burning is a game management tool. Location: Central Arnhem Land, a stronghold of traditional Aboriginal culture, in the monsoon tropics of northern Australia. Methods: The abundance of kangaroo scats was recorded throughout a landscape burnt by Aboriginal people, and used as a proxy for the intensity of habitat use by kangaroos. Scat abundance was assessed along field traverses totalling 112 km, at three time periods: (1) 1-4 weeks following mid-dry season burning (July 2003); (2) in the late dry season (November 2003); and (3) in the following mid-dry season (July 2004). We compared the intensity with which kangaroos used burnt vs. unburnt areas in various habitat types, with time since mid-dry season burning. Scats were collected from areas that had been burnt to a varying extent and the abundance of carbon and nitrogen stable isotopes (δ13C and δ15N) and carbon to nitrogen ratios (C : N) determined. Results: There was clear evidence of an interaction between burning and habitat type on the abundance of kangaroo scats. Scats were much more abundant in burnt vs. unburnt areas in the moist habitats, but the opposite effect was observed in the dry rocky habitats, with higher scat abundance in unburnt areas. This interactive effect of burning and habitat type on scat abundance was observed immediately (< 4 weeks) following fire, and was still present one year later. High concentrations of nitrogen in resprouting grasses indicate that burnt areas may provide kangaroos with greater access to nutrients. The isotopic composition of scats indicates that kangaroos feeding in extensively burnt areas were consuming more grasses, and possibly sedges, than kangaroos feeding in unburnt areas. Main conclusions: The fine-scale mosaic of burnt and unburnt areas created by mid-dry season Aboriginal landscape burning has clear effects on the distribution of kangaroos. Kangaroos move into burnt moist habitats and away from burnt dry, rocky habitats. Isotopic analysis of scats suggests that the mechanism driving this effect is the increased abundance of nitrogen rich grasses in burnt moist habitats. © 2007 The Authors.

Item Type:	Refereed Article
Research Division:	Environmental Sciences
Research Group:	Ecological applications
Research Field:	Landscape ecology
Objective Division:	Environmental Management
Objective Group:	Fresh, ground and surface water systems and management
Objective Field:	Assessment and management of freshwater ecosystems
UTAS Author:	Bowman, DMJS (Professor David Bowman)
ID Code:	50681
Year Published:	2007
Web of Science® Times Cited:	77
Deposited By:	Plant Science
Deposited On:	2007-08-01
Last Modified:	2008-05-17
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