FINAL REPORT

KAKADU MAMMAL HOTSPOT PROJECT (2005 to 2010)

Report compiled by Carol Palmer

Biodiversity Division

Department of Natural Resources, Environment, the Arts and Sport

September 2010

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Summary

The Kakadu Mammal Hotspot Project is a collaboration between Kakadu National Park

staff, traditional owners and scientists from the Northern Territory Government. The

project focuses on targeted mammal surveys with the aim of identifying “hotspot” areas

where small to medium weight mammals occur in Kakadu.

The project developed after an initial survey looking for the golden-backed tree-rat at

Deaf Adder Gorge during 2005, and which was the last known site for the golden-

backed tree-rat in the Northern Territory (NT). We didn’t find any evidence of the

golden-back tree-rat during that or subsequent surveys but the idea of a collaborative

mammal trapping program with the aim to identify areas of high mammal diversity,

train-up and work collaboratively alongside traditional owners and Kakadu staff was

developed.

The Kakadu Mammal Hotspot Project is a timely project because the decline in the

golden-backed tree-rat is now symptomatic of a more widespread decline of small to

medium sized mammals generally across the NT. Changes to fire regimes and grazing

by cattle and buffalo probably have impacted on the understorey trees, shrubs and

grasses that mammals rely on for food and shelter and with less cover it is easier for

feral cats to prey upon native mammals. Disease could also be a contributing factor for

this mammal decline.

Eight trapping surveys have been carried-out during the first stage of this project (2005

to 2010) and we have identified a number of sites that could be regarded as mammal

hotspot areas: Anlarr, Mamukala, West Alligator Head and Boggy Plains (see the map

at Figure 1). Moreover, 36 Kakadu staff and traditional owners have been involved in

the project.

The project has also promoted and worked alongside Kakadu’s Arnhem Land

neighbours, specifically the Warddeken Rangers who been involved in a number of

surveys within Kakadu and vice versa, where Kakadu staff and NTG scientists travelled

to Arnhem Land and undertook trapping there (see the 5-ways photo booklet Appendix

2).

Using photo-booklets the project reported back regularly to both Kakadu staff and

traditional owners as a record of the work undertaken (Appendix 1-5).

The project has also explicitly addressed and completed a range of issues identified as

priority actions in the Australian Government endorsed recovery plan for the golden-

backed tree-rat (Appendix 6) including:

• Develop and implement cooperative management arrangements

between relevant agencies, land managers and land owners

(Commonwealth, State, Territory and regional level).

• Investigate recent possible sightings/records of golden-backed tree-

rat.

• Indigenous participation and capacity building in relation to

threatened species management.

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• Develop appropriate educational and communication materials

targeted at the diverse range of stakeholders.

Finally, the project outcomes have a wide application for biodiversity conservation &

adaptive management strategies in other NT Parks & the broader landscape.

This report is a summary and collation of the work undertaken so far and outlines

recommendations for the second stage of the project.

Who has been involved in the mammal hotspot surveys

2005 to 2010

Kakadu NTG scientists Warddeken Rangers

Jessie Alderson Carol Palmer Lofty Bardyal Nadjamerrek

Jeff Lee Kym Brennan Peter Bilis

Sarah Nabulwad Mark Ziembicki Dean Yibarbuk

Jill Roberts Helen Haritos Serina Namarnyilk

Frear Alderson Brooke Rankmore Gareth Pamkal

Veronica Wellings Simon Ward Peter Cooke

Jessica Vigona David Liddle Ray Nadjamerrek

Ayasha Alderson Stuart Young Seraine Namundja

Rodney Nagawali Mikki Ensby

Stefan Anderson Alys Stevens

Gabrielle O’Loughlin

Evelyn Robinson Charles Darwin University

Joe Nagawali Helen Haritos

John Nadji

Samantha Deegan

Tida Nou

Sally-Anne Atkins

Mike Misso

Garry Lindner

Andrew Wellings

Greg Sattler

Mary Blythe

Dave Lindner

Brendan Mee

Evelyn Robinson

Gilbert Nabolbor

Trish Flores

Steve Winderlich

Victor Cooper

Steve Good

Fred Hunter

Paddy Cahill

Tim Henda

Charlie Whittaker

Buck Salau

Michelle Ibbett

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Where and when we trapped for mammals

Survey site When Photo-booklet (Appendix 1 to 5)

Deaf Adder Gorge 2005 & 2006 yes (2005 only)

5-ways 2008 Yes

Anlarr 2009 Yes

Mamukala 2009 No

West Alligator Head 2009 Yes

Field Island 2010 Yes

Boggy Plains (south) 2010 No

Figure 1. All trapping site locations for the Kakadu Mammal Hotspot Project

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Table 1. The number of mammals we have caught and where we caught them

Species Deaf

Adder

2005

Deaf

Adder

2006

5 -

Ways

2008

Anlarr

2009

Mamukal

a

2009

West

Alligator

Head

2009

Field Island

2010

Boggy

Plains

(south)

2010

Fawn

antechinus 13 2 17

Sandstone

False

Antechinus

2

Common

planigale 3

Red-

cheeked

dunnart

1

Northern

brown

bandicoot

2 4 22 1

Common

brushtail

possum

2 3 1

Grasslands

melomys 4 1 7 10 15 13 1

Common

rock-rat 1 1 3

Arnhem

Land rock-

rat

6 7 14

Black-

footed tree-

rat

1 3

Pale-field

rat 1

TOTAL 11 13 26 29 30 18 14 20

Table 2. Total number of trap nights, trap success and number species

Deaf

Adder

2005

Deaf

Adder

2006

5 -

Ways

2008

Anlarr

2009

Mamukala

2009

West

Alligator

Head 2009

Field

Island

2010

Boggy

Plains

(south)

2010

Total

no. of

trap

nights

936 861 532 936 1160 643 480 800

Trap

success

%

1.1% 1.5% 4.8% 3.0% 2.5% 2.8% 2.9% 2.5%

No. of

species 3 6 4 4 4 2 2 4

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What does it all mean?

The overall picture for many native mammals in northern Australia is pretty bleak and

we can expect to lose native mammals even in Kakadu. Many native mammals are in

sharp decline and we know this from the robust scientific monitoring programs that are

undertaken in Kakadu and other national parks but also from surveying long-term

Aboriginal residents in remote outstations across the Top End.

The main drivers for native mammal decline include frequent and hot dry season fires

and predation by feral cats. The Northern Quoll has had a catastrophic decline due to

cane toads. Changing vegetation associated with cattle and potentially disease could be

all factors in our declining native mammals.

Where to from here?

The Kakadu Mammal Hotspot Project has identified a number of areas where targeted

adaptive management could be undertaken and could include a component of

monitoring in these hotspot areas.

However, that approach changes the original focus of the project which was to engage

and up skill traditional owners and Kakadu staff in wildlife survey techniques

specifically aimed at native mammals and identifying areas of high mammal diversity.

Options for stage 2 include:

• Continue with the same methodology presented in this report

• Undertake targeted threatened species monitoring

• Mix and match – continue and expand on hotpot surveys but also undertake

targeted adaptive management strategies at a number of the hotspot sites already

identified i.e. specific fire management, introduce exclosure areas or install

camera traps in these areas to estimate abundance of feral cats / dingoes, include

a number control sites; and at some point undertake feral animal control but

continue to monitor populations as the adaptive management is undertaken.