How was the prickly pear biologically controlled in Australia?
The most famous example of biological control of weeds is the use of a cactus moth, Cactoblastis cactorum, for control of prickly pear cactus (Opuntia spp.) in Australia [11]. This plant was introduced into Australia for the production of red dye that was produced by the cochineal insects that fed on the cactus.
What biological control was used to get rid of the prickly pear?
The Argentine cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), an invasive pest native to South America that feeds on prickly pear cactus ( Opuntia spp.), has been used as an effective biological control agent against exotic Opuntia cacti around the world, including several Caribbean islands, Hawaii …
Is prickly pear still a problem in Australia?
An ongoing problem Although not on the same scale as the 1920s crisis, prickly pear continues to be a problem in New South Wales and Queensland, where new varieties that do not act as hosts for cactoblastis moths have become established.
Why was prickly pear a problem in Australia?
Prickly pears (mostly Opuntia stricta) were imported into Australia in the First Fleet as hosts of cochineal insects, used in the dye industry. Many of these, especially the Tiger Pear, quickly became widespread invasive species, rendering 40,000 km2 (15,000 sq mi) of farming land unproductive.
How did Cactoblastis moth control prickly pear?
The CPPB sent botanists to America to find the best way to destroy prickly pear. They recommended the Cactoblastis cactorum moths from Argentina. The female moths lay eggs on prickly pears, and their larvae eat and destroy the plant in a few weeks.
What is the biological control?
Biological control is the use of living organisms to suppress pest populations, making them less damaging than they would otherwise be. Natural enemies of insects play an important role in limiting the densities of potential pests.
How do you get rid of prickly pear cactus in Australia?
Use mechanized equipment such as front-loaders to remove above-ground prickly pear growth. Wear protective clothing and safety glasses. Load prickly pears into vehicles for hauling away and discarding. Alternatively, use mulching and grinding equipment to shred the cactus pieces.
Why was the cactus moth introduced to Australia?
The cactus moth was introduced into Australia from Argentina in 1925 as a biological control measure against the prickly pear cactus. Laetilia coccidivora is an unusual caterpillar in that it is predatory, feeding on the eggs and young of scale insects.
What problems do prickly pears cause?
The spines are capable of causing serious injury to humans, stock and native animals. Large stands of cacti can harbour feral animals, limiting access for stock mustering and recreational activities. Spines can contaminate wool and hides, and infestations can reduce or prevent grazing activities, reducing productivity.
When was the Cactoblastis moth introduced to Australia?
1925
In 1925 the Commonwealth Prickly Pear Board, realising the scale of the problem, introduced the Cactoblastis moth and larva from South America (Cactoblastis cactorum).
What are some examples of biological control?
Some notable examples of classical biological control include the use of decapitating flies (several Pseudacteon species) against red imported fire ants, and a group of flea beetles, thrips, and stem borers used against alligator weed.
What are 4 biological methods of controlling pests?
Biological control of potential pest insects can be increased by: 1) conservation of existing natural enemies, 2) introducing new natural enemies and establishing a permanent population, and 3) mass rearing and periodic release of natural enemies, either on a seasonal basis or inundatively.
How do you control prickly pear trees in Australia?
And, biological control continues to play a very significant role in controlling various prickly pear species in Australia, particularly in the drier, warmer areas. The two most important biological control agents are COCHINEAL and CACTOBLASTIS. The two are entirely different! ( Cochineal PDF print version available – 3 pages)
How was common pest pear eradicated in Queensland?
Common pest pear once covered vast areas of Queensland, until it was successfully controlled by the biological control agent in the late 1920s, Cactoblastis cactorum. Although common pest pear was not completely eradicated, the agent achieved an acceptable level of control.
When did the prickly pear Epidemic End in Australia?
By 1933 it was estimated that 80 per cent of the infested land in Queensland, and 50–60 per cent in New South Wales, had been cleared. This was the turning-point in the fight against prickly-pear in Australia.
What is Opuntia stricta (prickly pear)?
Opuntia stricta (prickly pear) was introduced into Australia around 1840, but became a pest of epidemic proportions in the first two decades of the 20 th century. It eventually infested 30 million hectares in 1930 in a wide area around Brisbane.