Vast lands and variable data: systematic analyses to understand the patterns and processes of mammal decline, ACEAS Grand 2014, Alex Kutt and Chris Johnson

1. Vast lands & variable data:
systematic analyses to understand
the patterns and processes of
mammal decline

2. Small-mammal declines in northern
Australia
Alex Kutt, CSIRO
Chris Johnson, JCU/UTas
Diana Fisher, UQ
Michael Lawes, CDU
Susanne Fritz, BiK-F Germany
Hamish McCallum, UQ
Jeremy VanDerWal, JCU
Colette Thomas, CSIRO
Alaric Fisher, NT DLRM
Iain Gordon, CSIRO
Brett Abbott, CSIRO
Anke Frank, JCU/UTas
Sarah Legge, AWC
Michael Letnic, UNSW

3. Small mammals in Kakadu NP,
Woinarski et al. (2011) Cons Lett

5. Problems in diagnosing cause
Lots of contenders: fire, grazing, cats,
climate/weather, disease, toads…
Patchy survey, observational & historical data,
spread unevenly over a vast area
Almost no in-depth study of declining
populations
Declines happening fast

6. Our aims:
Collate and analyse existing data & evidence
Evaluate hypotheses/formulate new hypotheses
Guide new policies for land management

7. Some results and impacts

8. 1. Review of hypothesis set, through a formal
deliberative process
Interaction of factors crucial:
predation by feral cats, interacting with fire and
grazing

10. 2. Comparative analysis
of traits associated
with mammal decline,
north and south
[size, life history,
ecology, climate etc]

11. Small body size and open habitat predict decline
Similar to past declines in the south
But smaller species affected in the north
The main results:

12. 3. Improved distribution/abundance
database for Australian mammals
Data from fauna surveys, added to museum
(etc) data; > 600,000 records
Better models of distribution & change due to
climate/weather – work continuing
see mammal distribution visualisation portal

14. Thanks ACEAS