New effort to save Australia's rarest freshwater fish

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Scientists have begun collecting samples from Australia's rarest freshwater fish species in a new effort to save them from extinction.

The Red-finned blue-eye, Scaturiginichthys vermeilipinnis (pictured above) is now restricted to just four known populations all found in artesian springs at Aramac in central-west Queensland on the Edgbaston reserve owned and maintained by conservation group Bush Heritage. 
 
Tiny samples from the tail of over 200 fish have been taken to extract DNA for two purposes. 
The first is to check how closely related genetically the four known populations are, so if captive breeding or relocation to other sites is required, the risk of inbreeding is minimised. 
The second reason is simply scientific evolutionary curiosity - finding out how the fish arrived at their location, in what ways they have evolved to survive there and whether or not they move from spring to spring. 
Action to save the blue-eye is needed for a number of reasons. Their habitat is being invaded by the mosquito fish, (Gambusia holbrooki) an introduced species, so special fencing has been installed around some of the springs to prevent seasonal flooding allowing the Gambusia to access them. Also, the springs themselves are being damaged by feral pig populations, so shooting and trapping of these is taking place. Water harvesting from the Great Artesian Basin is also thought to be playing a part in damaging their habitat.
The springs are also home to another unique fish species, the Edgbaston goby, Chlamydogobius squamigenus as well as several endemic species of invertebrate including flatworms, snails, leeches and spiders all of which are under threat for the same reasons as the blue-eye, 
The Red-finned blue-eye grows to around 2.5cm/1in and is well adapted to the extreme environment it inhabits where temperatures can vary from 51C in summer to 3C in winter, but is unable to compete with the Gambusia largely because the introduced fish is a livebearer, while the blue-eye lays eggs. 
Both Scaturiginichthys vermeilipinnis and Chlamydogobius squamigenus are listed as 'critically endangered' on the IUCN 'red list', less than 20 years after they were described to science.