![]() ![]() The premise of island size contributing to diversity is based on the fundamental ecological concept-the species area relationship (SAR). Island biogeography is based on the idea that the larger an island, and the less it is isolated from other areas, the higher the biodiversity it contains. Opportunities to mitigate threats are discussed, along with directions for future research to improve management of this extremely threatened fish and habitat. Three attempts to translocate RFBE to apparently suitable springs elsewhere within the complex have failed. The impact of Gambusia is probably exacerbated by domestic stock (cattle and sheep), feral goats and pigs that utilise the springs and can negatively affect water quality and flow patterns. Circumstantial evidence suggests that gambusia is a major threat to red-finned blue-eyes. Four out of the five remaining subpopulations of RFBE are Gambusia free. Gambusia was present in four of the five springs where RFBE populations have been lost. There is evidence of spatial separation within the spring pools where RFBE and the introduced fish gambusia (Gambusia holbrooki) co-occur, although both species are forced together when seasonal extremes affect spring size and water temperature. Artesian bores have reduced aquifer pressure, standing water levels and spring-flows in the district. Current population size is estimated at <3000 individuals. Since its discovery in 1990, five red-finned blue-eye (RFBE) populations have been lost and subsequent colonisation has occurred in two spring wetlands. The species has been recorded as naturally occurring in eight separate very shallow (generally <20 mm) springs, with a combined wetland area of ~0.3 ha. The red-finned blue-eye (Scaturiginichthys vermeilipinnis) is endemic to a single complex of springs emanating from the Great Artesian Basin, Australia. ![]()
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