Integrating western and Indigenous knowledge to identify habitat suitability and survey for the white-throated grasswren (Amytornis woodwardi) in the Arnhem Plateau, Northern Territory, Australia

Abstract

Context

Many Australian threatened species occur on Indigenous-owned and/or managed lands, often in vast, remote areas that are difficult and expensive to access. One such species is the white-throated grasswren (WTGW, Amytornis woodwardi), a rare ground-dwelling bird found in rocky spinifex-covered escarpment habitats of northern Australia. To make surveying rare species more tractable, we can predict habitat suitability by associating occurrence points with environmental covariates that may influence the species’ distribution.

Aims

Here, we combine western and Indigenous knowledge and approaches to better quantify the habitat associations and distribution of the WTGW.

Methods

We modelled habitat suitability across the region using historical occurrence records and applicable environmental variables with input from Traditional ecological knowledge. We then used this habitat-suitability map as a visual tool for participatory mapping and planning sessions with Traditional Custodians to select on-ground survey sites. Collaborative surveys were then undertaken to target WTGWs at 39 sites across the Arnhem Plateau by using several methods, including bioacoustic audio recorders (BARs), call-playback (CPB) surveys, and motion-detection cameras.

Key results

Collaboration between Traditional Custodians and scientists at all stages helped make this project a success. Our model suggests that WTGWs typically occupy habitat patches that have lower distance-to-unburnt (fire extent) values, lower proportion-of-area-burnt values, lower vegetation-cover values, and higher time-since-fire values. On-ground surveys detected WTGWs at six sites with BARs and at one of these six sites with CPB and camera-trapping, suggesting that BARs were the most effective detection method.

Conclusions

Our results provided key ecological information for use by land managers in the region and highlighted the importance of effective fire management for the persistence of WTGW populations. The success of the cross-cultural collaboration across several Indigenous organisations relied on the expertise of Traditional Custodians and Indigenous rangers. With Traditional Custodians and Indigenous rangers leading the fieldwork, co-benefits of the program included connecting people with Country and supporting the transfer of intergenerational knowledge surrounding the WTGW.

Implications

Whereas fire management in the region over the past decade has led to broadscale reductions in the frequency, extent and intensity of fires, strategic imposition of fire regimes that retain sufficient unburnt refugia at habitat scales appears necessary for viable populations of species such as the WTGW to persist.