Eastern Australia Rivers & Streams - A Global Ecoregion
Home to many species of ancient Gondwanan origin
Snapshot: Ecoregion 169
1,900,000 sq. km (750,000 sq. miles)
Habitat type:
Small Rivers
Geographic Location: Eastern Australia, including Tasmania
Conservation Status:
Critical/Endangered
Quiz Time!
What is so peculiar about the gastric brooding frog?
Answer:
Endemic to the Eastern Australia Rivers and Streams ecoregion, "was" the gastric brooding frog - a species scientists fear might be extinct. The female of the species swallows the fertilised eggs, and they incubate in her stomach for about six weeks.
During this time, the stomach stops producing digestive juices. At the end of this period, as many as 21 baby frogs jump out of her mouth over a period of about a week.
About the Area
In contrast to streams in western regions, the fast-flowing waters of Eastern Australia are high both in species richness and endemism.
This ecoregion also includes the rivers and streams of Tasmania, a small island off of the coast of southeastern continental Australia.
This island receives abundant rainfall as compared to much of the mainland. Found here are numerous relict species, including many species of dragonflies (Odonata), mayflies (Ephemeroptera), and mountain shrimp (Syncarida) - the latter restricted to Tasmania.
Local Species
Southeast Australia has a particularly species-rich and endemic crayfish (family Parastacidae) fauna. The most famous resident of eastern Australia's freshwater systems is the Platypus (Ornithorhynchus anatinus). The ecoregion also includes an unusual group of gastric-brooding frogs in the genus Rheobatrachus.
Among the many endemic fishes is Murray jollytail (Galaxias rostratus), the primitive spotted Bonytongue (Scleropages leichardti), and the migratory Australian grayling (Prototroctes maraena), which may be the only living member of its genus and is considered vulnerable.
Tasmania has a highly endemic fish fauna of its own, including Shannon paragalaxias (Paragalaxias dissimilis) and Tasmanian whitebait (Lovettia sealii). The island is also home to 15 species of galaxiid fishes in three genera. Distinctive endemic crayfish include the massive Tasmanian Astacopis gouldi, and the diminutive Tenuibranchiurus glypticus.
Threats
Threats comprise construction of weirs and dams, channelisation, removal of riparian vegetation, agricultural, urban, and industrial pollution, introduced species, aquaculture, forest clearing for agriculture and timber production, and the subsequent increase in sedimentation.
Resources
• NationalGeographic.com
