Predicting habitat suitability for wild deer in relation to threatened ecological communities in south-eastern New South Wales, Australia

Context. High density deer populations can cause ecological damage, yet
their distribution and impacts are poorly known across much of Australia.
As a result, land managers rely on anecdotal reports to make decisions
about management and control measures. Aims. We aimed to model habitat
suitability for deer in the South Coast of New South Wales (NSW),
Australia, to be used as a baseline for future management and identify
which threatened ecological communities (TECs) in the region are at
greatest current risk of being occupied by deer. Methods. We compiled 678
presence-only records of wild deer from online databases, observations
made by National Parks and Wildlife Service field staff and field-based
surveys. We combined these observations with eight environmental variables
to model and map habitat suitability for deer across our study area using
maximum entropy. Three spatial models of habitat suitability across our
study area were produced: one for all deer species; and two
species-specific models for fallow and sambar deer. Key results. Our
models indicate that suitable habitat for deer exists throughout much of
the South Coast of NSW. Of the TECs examined, Coastal Saltmarsh, Themeda
Grassland, and Swamp Sclerophyll Forest had the highest proportion of area
likely to be extremely suitable for deer and thus should be prioritised
for protection within our study area. Conclusions. Further systematic
field-based surveys are needed to improve the quality of models in this
region. Implications. We recommend that areas having high habitat
suitability but are not yet occupied by deer be identified as sites where
deer occupancy could be prevented.