PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
LIST OF SOME
VERTEBRATE
PESTS
Fruit bat
Rodents have
chisel-like front
teeth for gnawing
BIRDS.
Cockatoos, rosellas
– Fruit and nuts, eg almonds, pome fruits, walnuts.
– Flowers, eg daffodils, roses. Parrots and other birds tear open the canes of new
spring growth of roses and other flowers seeking to eat soft green tissue.
– Shoots, stems, eg eucalypts, wattles, especially pistachio. They tip prune new
shoots during their quest for seed and tear open stems of young trees
in plantations to prey on larvae of various borers.
– Conifer leaders are damaged by their efforts to obtain cones.
Sparrow, starlings, silver eyes, wattle birds, currawongs
– Vegetable seedlings after planting out, eg lettuce, spinach, beet.
– Strawberry fruit and soft-skinned fruit, eg stone fruit, grapes.
– Currawongs eat whole berries on grapevines.
Ducks, emus, geese eat seed and flatten crops, leaving messy droppings.
Magpies swoop people during spring to protect their young in nests.
Bell miners have been associated with the psyllid infestations on eucalypts in some
plantations resulting in tree decline, to the extent that the association has been listed
as a key threatening process under the Threatened Species Conservation Act.
Silver gulls have profited from access to unlimited food at rubbish tips and are a
hazard to aircraft at airports. Pigeons leave droppings in urban parks and buildings.
Seagulls in coastal towns.
Birds with sharp beaks seeking scarab grub larvae damage turf and lawns.
Birds may spread diseases such as avian flu and psittacosis.
The Australasian Pest Bird Network was developed to encourage discussion
on pest birds, keep up-to-date with current research and provide an avenue for
requesting information. Global Flyway Network (GFN) in Broome check long
distance migrating shorebirds, eg magpie geese.
Noise complaints, customer complaints.
Tracey et al (2007) has written a comprehensive treatise on managing bird damage
to fruit and other horticultural crops.
FRUIT BATS, FLYING FOXES.
Fruit bats, flying foxes (Dobsonia spp., Pteropus spp.) are protected wildlife.
They live in colonies in trees during the day. At night they leave to feed on mostly
native fruits but will also feed on soft cultivated fruit and attack orchards for
mangoes, nectarines and peaches, etc. Bats can travel over great distances. Some
fruit bats are important pollinators of native plants. Some native animals feed on the
fruit of trees pollinated by fruit bats.
Insectivorous bats eat up to half their body weight in insects, eg moths, beetles,
flies, flying ants, each night. It is not possible yet to establish the effect of bats on
reducing plant pests. May be seen at night in urban areas around street lights.
Bats may carry viruses, eg Australian bat lyssavirus (ABL) and the equine
morbillivirus (affects horses), both of which can infect humans. Bats and flying
foxes constitute a particularly fertile source of virus.
Bat droppings may contaminate swimming pools, drinking water.
RATS AND MICE.
Prodigious rate of reproduction. A single pair of mice under optimum
conditions can produce >300 mice in 21 weeks (5 months). A mouse plague in
SA (1993) cost an estimated A$100 million in crop, stored grain and other losses,
in SE Asia it is common for villagers to lose half their rice crop to rats.
Rats and mice are serious agricultural and horticultural pests.
– Both introduced and native species can be pests.
– They damage crops, pastures, stored grain, vegetables in storage, etc. and contaminate
it with their faeces. They also eat bulbs, rhizomes, seeds, macadamia nuts and other
plant materials. Rats also eat young chickens, eggs etc.
– Rats harbour diseases and pose a serious threat to human health, eg bubonic
plague bacteria is spread to humans by the Oriental rat flea.
– Rats in sugarcane in north NSW and Qld spread typhus and other diseases.
– Toxoplasmosis which causes huge losses of life in livestock is a serious problem in
humans in the USA and other countries. The parasite (a protozoan) passes from rats
to cats to humans.
Rodents are, in general, increasing in numbers.
– Evolution scientists warn of damage to the global environment with animals and
plants such as rats, cockroaches, nettles and thistles flourishing at the expense of
more specialized wild organisms.
– Factors contributing to the rise in rat numbers in the UK include global warming,
privatized water authorities and associated continuing decay of urban sewerage
systems, use of plastic building materials which can be more easily eaten by rats, fast
food outlets contributing to increased levels of rubbish, reduced pest control funding
by local authorities, pesticide-resistant rats and an unwillingness of some people
to use rodenticides.
Vertebrate pests 241