WfHC - cover page (not to be used with pre-printed report ... - CSIRO

Figure 79. Early-dry season fire scars during 2012 for the Oriners/Sefton area, with all fires lit
by humans in a coordinated ground and air based traditional fire regime program. Data are
from the Northern Australia Fire Information (NAFI) website (www.firenorth.org.au).
3.3.5 Feral animals and stock
Since European settlement of Australia, numerous exotic animals have been introduced
deliberately or indirectly to the Australian landscape (Cotter 1995; Mitchell and Hardwick
1995) . In the area around Oriners and Sefton on Cape York, the main exotic and/or feral
animals are domestic and wild cattle (Bos spp.), wild pigs (Sus scrofa), and feral cats (Felis
catus). Naturalized wild dogs (Canis lupis dingo) are also present. Current population
estimates for these animals are currently unknown for the Oriners and Sefton areas.
Since Oriners and Sefton Stations are largely unfenced and unmanaged for cattle
production, both domestic cattle from adjacent stations and wild cattle populations have
relatively easy access to the properties. However, current cattle populations are likely fairly
low and only locally concentrated, and future muster efforts will be needed to assess current
populations. However during 2012, early dry-season fires (Figure 79) brought many wild
cattle onto Eight Mile Creek frontage country and new green pick, indicating that wild cattle
across the landscape might be more numerous than thought. Mustering programs by
adjacent station regularly retrieve stray domestic animals. However domestic cattle are
occasionally missed and unrecovered, possibly contributing to the already existing wild cattle
herds from earlier utilized breeds and grazing practices.
The ecosystem impacts of unmanaged wild and domestic cattle herds on Oriners and Sefton
stations could include: 1) the direct consumption of native grasslands, 2) competition for feed
with native animals (wallabies, kangaroos, termites etc), 3) alteration of grass fuel loads for
specific preferred fire regimes, 4) spread of exotic weeds, 5) spread of disease to domestic
cattle and other animals, 6) altering the vegetation (macrophyte) habitat and water quality of
waterholes used for watering points (Pettit et al. 2012 in press), 7) direct surface erosion
through soil disturbance, and 8) initiation of gullying along alluvial banks of rivers, creeks,
and waterholes from cattle pads and localized overgrazing (Shellberg et al. 2010; Shellberg
2011). However these potential impacts are scalded by herd size and an assessment of
animal numbers will be the only way to directly assess their potential impact at the landscape
level.
Wild pigs are relatively abundant on Oriners and Sefton Stations, similar to other properties
on central Cape York. Government funded population control and eradication programs for
wild pigs using poison baits and aerial shooting are widespread across Cape York, but efforts
are spatially and temporally variable and at times inconsistently managed and funded.
Working Knowledge at Oriners Station, Cape York
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