PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
LIST OF SOME
VERTEBRATE
PESTS
(contd)
There has probably
been more written
about the rabbit than
any other vertebrate
pest in Australia
.RABBITS.
Rabbits because of their prodigious rate of reproduction are probably the best
known vertebrate pest in Australia. They:
– Cause millions of dollars damage to agriculture in Australia each year.
– Eat vast quantities of pasture, crops; damage trunks of young trees, newly planted
nursery stock and native vegetation that provide food and shelter for native animals.
– Change pasture composition, compete with livestock.
– Erode soil by digging their burrows and have been responsible for more ecological
damage in the history of Australia than any other single factor to date.
Rabbits are a good example, how difficult vertebrate pests are to manage.
Despite the rabbit-proof fence, metal trapping, harbor destruction by burning and
warren destruction by ripping, fumigating warrens, poison baiting and the use of
virus diseases, we still have rabbits!!!!
Rabbits and rats pose a severe threat to World Heritage values on Macquarie
Island. Impacts include devastating effects upon native fauna, flora, geomorphology,
natural landscape values and nutrient recycling systems. A Draft Plan for the
Eradication of Rabbits and Rodents on Macquarie Island has been developed which
includes baiting and other options such as using dogs to find any remaining rabbits,
as necessary. Rabbits will need to be monitored for several years after eradication to
ensure that no rabbits escaped the program.
The Rabbit Scan Website is designed for farmers and landowners to plot the
spread and distribution of rabbits and warrens on their land. A map of rabbit
populations Australia-wide from there they can work to eradicate problem areas. The
Australian Wildlife Conservancy (AWC) controls 6.2 millions of Australian bushland
which has been fenced off from feral animals allowing return of native animals and
plants in these areas.
Rabbits in bushland may be monitored by counting small clumps of pellets,
scoring seedling abundance, regeneration and overall rabbit impact, before and after
rabbit removal. An Australian Government, Bureau of Rural Resources website
provides an overview of rabbits in Australia.
Rabbits: A Threat to Conservation & Natural Resource Management.
www.feral.org.au/content/speces/rabbit.cfm
.KANGAROOS, WALLABIES, POSSUMS.
Kangaroos and wallabies consume grass in pasture and native areas, cereal
and other crops when available, and newly planted nursery stock.
Possums in urban areas feed on new buds on grapevines, pistachio and other
plants, also on fruit, eg pome and stone fruit, and nuts, eg walnuts. Major pest in
New Zealand.
.DOGS, FOXES, DINGOES, CATS.
Dogs and cats are not parasitic on plants but can damage lawns, dig up plants.
Cats may soil gardens and scratch the bark of trees. Eat a range of wildlife,
including wrens, parrots, frogs, native mice .
Wild dogs in Nature Reserves adjacent to agricultural areas attack sheep.
Dogs may attack people, especially children.
SPREAD,
CONDITIONS
FAVOURING
Know why pests
are attracted to
an area
1 pair of rabbits
can produce
more than
180 offspring
in 18 months
The source of vertebrate pests in Australia are from many sources, including:
Many were brought into Australia in the early days of settlement for food,
recreation, etc.
Others entered Australia accidentally, eg on containers, refugee boats.
Some were deliberately and legally brought in for various reasons, eg cane toads
for the biological control of sugarcane grubs.
Some have been brought in deliberately and illegally, eg by air travelers.
Within Australia by natural spread, and deliberately, eg Indian Myna. Camels,
horses, goats were let loose after their farming needs were met.
Numerous conditions favour both exotic and native vertebrate pests, eg
– Lack of predators for introduced feral species.
– Australia farming is extensive and often inadequately fenced.
– Environmental. Mouse plagues after mild winters so that females survive to breed
in spring and autumn. Above average rainfall may trigger a mouse plague.
– Breed prolifically. The expression ‘breed like rabbits’ is well known. Most
vertebrate pests breed prolifically when conditions are favourable.
– Some are long lived, eg bats live for 20 years.
– Plentiful food for mice from higher yields, continuous cropping, irrigated crops,
increased stubble retention in minimum tillage.
– Shelter. Mice look for warmth and shelter in burrows in the soil, raised beds,
storage areas, minimum tillage farming. Rabbits retreat to their burrows in weed
thickets. Indian mynahs nest in garden conifers.
242 Vertebrate pests