Introduced+Species

By Carol and Annmarie
 * Introduced Species research**

Introduced species are foreign species that have been introduced accidentally or intentionally. Once introduced species have discovered self-supporting populations in the wild, they are claimed to be //feral//. They are also known as foreign, exotic or alien.
 * __What is it?__**

Feral animals and plants are so successful because they can out-breed, out-eat and out-compete Australian natives, they also have a great population because they only have a few natural predators. These feral invaders cause massive damage to the Australian environment.
 * __What is the problem?__**

This damage to the environment has led Australian Scientists to develop different ways to control the pests numbers. They discovered that poisons are often ineffective because they can also cause environmental damage. Physical control, through shooting or removal of individuals, involves high energy and high cost. So scientists started looking towards biological control which is to use living organisms to control the spread of the feral species.
 * __Control__**

__Explain why species may become a pest when introduced into a new land, when it was not a pest in its country of origin?__ When introduced into a new land, there may be no predators. There's nothing that eats it, and so it reproduces very fast. In its place of origin, there must be something that preyed on it, keeping its population down.

There is a variety of introduced species in Australia, therefore sub-classifications are necessary, there are three classifications:
 * //[|Invasive]//
 * //[|Ferals]//
 * //[|Pests]// [[image:file:///Users/carokong/Library/Caches/TemporaryItems/moz-screenshot.jpg]]

__**This table shows some examples of animal introduced species (vertebrates):**__ (see [|Australian feral camel]) || [|Camelus dromedarius] || 1840 || Beast of Burden || India || Central Australia (extensive) || Yes || Yes || Low || __**Introduced plant species in Austraila:**__
 * ~ Image ||~ Name ||~ Species ||~ First Introduced ||~ Reason First Introduced ||~ Introduced from ||~ Current Extent/Distribution ||~ Invasive ||~ Feral ||~ Pest ||
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/0/09/Blackbird_2.jpg/50px-Blackbird_2.jpg width="50" height="35" link="http://en.wikipedia.org/wiki/File:Blackbird_2.jpg"]] || Blackbird || [|Turdus merula] || 1860s || ? || northern [|Europe] || [|Victoria] (extensive), [|South Australia], [|New South Wales], [|Tasmania], [|South East Queensland] || Yes || No || Yes ||
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/8/85/Bufo_marinus_from_Australia.JPG/50px-Bufo_marinus_from_Australia.JPG width="50" height="41" link="http://en.wikipedia.org/wiki/File:Bufo_marinus_from_Australia.JPG"]] || Cane Toad || [|Bufo marinus] || 1935 || Biological Control ([|Cane beetle]) || Hawaii || [|Queensland] (extensive), northern [|New South Wales], [|Top End], [|Kimberley] || Yes || No || Yes ||
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/8/80/Kaninchen.jpg/50px-Kaninchen.jpg width="50" height="48" link="http://en.wikipedia.org/wiki/File:Kaninchen.jpg"]] || European Rabbit || [|Oryctolagus cuniculus] || 1859 || hunting; the rabbits provided early settlers with a ready source of meat. || Europe ||  || Yes || Yes || Yes ||
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Vulpes_vulpes_sitting.jpg/50px-Vulpes_vulpes_sitting.jpg width="50" height="33" link="http://en.wikipedia.org/wiki/File:Vulpes_vulpes_sitting.jpg"]] || Red Fox || [|Vulpes vulpes] || 1855 || Hunting || Europe ||  || Yes || Yes || Yes ||
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/b/bb/Camelus_dromedarius_in_Singapore_Zoo.JPG/50px-Camelus_dromedarius_in_Singapore_Zoo.JPG width="50" height="38" link="http://en.wikipedia.org/wiki/File:Camelus_dromedarius_in_Singapore_Zoo.JPG"]] || Dromedary Camel

__1. Water Hyacinth //Eichhornia crassipes://__
 * __Place of origin:__ Amazon River basin of SA
 * __When introduced:__ 1890s
 * __Reason introduced:__ to allow it to grow and spread rapidly in fresh water
 * __Type of damage:__ form dense mats that interfere with: navigation, recreation, irrigation, power generation. Low oxygen conditions develop under water hyacinth mats and the dense floating mats impede water flow and create good breeding conditions for vectors of human and animal diseases.
 * __Control:__ several bio control agent were released in Australia in the 1920s and 1980s. Two weevils, a moth and two types of fungi have been introduced to successfully control the plant.

__2. Prickly Pear //Opuntia spp.//:__
 * __Place of origin:__ Native to the Caribbean region
 * __When introduced:__ late 1800s (1840s)
 * __Reason introduced:__ could feed animals in time of drought
 * __Type of damage:__ invades pastures, vigorous in hot, dry conditions causing other plants to lose vigour or die.
 * __Control:__ nine established insects and one mite biological control agents established in Queensland, fire is an effective control method for dense prickly pear infestations.

Over 28,000 foreign plants have been introduced in Australia most are both deliberate and accidental. A total of 29,430 species are listed including 606 Australian species that have been naturalised (i.e. human intervention) outside their native range

__Possible causes__

The actions/events/situations that might induce this stress:
 * Aquaculture escapees
 * Aquarium releases
 * Dumping garden refuse/rubbish
 * Escape of weeds from gardens
 * Transport via boat hulls, fishing/diving gear, ballast water and infrastructure
 * Transport of pests via dredge spoil

__Possible symptoms__

The actions/events/situations that might arise from a change to the stressor:
 * Algal blooms of pest species
 * Animal kills
 * Biodiversity decreased
 * Habitat lost/disturbed
 * Nuisance growth of aquatic plants
 * Paralytic shellfish poisoning
 * Pest outbreaks
 * Seafood catch or stock (changed)
 * Changed species composition
 * Altered ecosystem function

**__Feral Species__ __and domesticated animals__** The term feral  refers to any type of animal or plant that was once domesticated but has now returned to the wild. //Domesticated// animals become feral  when they are released, abandoned or if they escape from human captivity. A feral  animal not only include the once domesticated individuals but also any offspring the animals may have or will produce after they have become  feral. Domestic could be applied to animals that are used by human beings, while feral could be defined in terms of the animal's distance from, and unfamiliarity with human beings.

__URLs:__ http://en.wikipedia.org/wiki/List_of_introduced_species [accessed date: 27/6/09] http://soer.justice.tas.gov.au/2003/bio/4/issue/19/ataglance.php [accessed date: 25/6/09] http://www.questacon.edu.au/indepth/clever/control_ferals.html [accessed date: 25/6/09] http://en.wikipedia.org/wiki/Oryctolagus_cuniculus [accessed date: 1/7/09] http://en.wikipedia.org/wiki/Vulpes_vulpes [accessed date: 1/7/09] http://weeds.cbit.uq.edu.au/ [accessed date: 2/7/09] www.ozcoasts.org.au/env_mgmt/stressors/pests.jsp [accessed date: 2/7/09] http://www.wisegeek.com/what-are-feral-animals.htm [accessed date: 9/7/09] http://www.associatedcontent.com/article/1508422/what_is_the_difference_between_domestic.html [accessed date: 9/7/09]