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waterways

Many of the waterways in the Daintree, for example Cooper Creek, are exceptionally unique, with high levels of known endemism (species that exist only in the defined area) and exceptional cultural value to the Kuku-Yalanji people. They are also extremely beautiful and refreshing, but they are changing. Long-time residents recall the creeks running clear except in exceptionally heavy rainfall.  Now many of them run brown with the first downpour.  The severities of the threats they face are poorly understood, but it is the pigs that are the most significant contributor to erosion.

The freshwater fish fauna in the Daintree River through to the Cape Tribulation area is nothing short of outstanding by Australian standards. The short-steep-coastal-streams that have been surveyed to date support a recently discovered assemblage of cling gobies. These small fish have a suction cap on their underside enabling them to cling to rocks on the stream bed and are shared species with similar stream types in the tropical Pacific Islands (e.g. Solomon Islands and Fiji). The Daintree River and Cape Tribulation streams are also a stronghold for the elusive freshwater moray, the world’s only known species of freshwater moray (eel). Many of the species in this part of the Wet Tropics are diadromous, meaning they spend some part of their life in freshwater and another part of their life in the sea.

There are also some fish species occupying the Daintree River and Cape Tribulation streams that exclusively live in freshwater for their entire life cycle. Of these, at least five are small-bodied species, including an undescribed species of rainbowfish from the Cooper Creek catchment. The latter species is found nowhere else in the world. There are also two larger-bodied fish species that are endemic to the Wet Tropics found in the Daintree River. These are the Tully grunter and the tropical tandan (a catfish). The tropical tandan is also found in some of the larger Cape Tribulation streams, and it’s large nests can sometimes be seen in Myall Creek (especially downstream of the main road) but be careful because this is crocodile country.

The freshwater fishes of this region face numerous threats. There are alien fish species (e.g. guppies) in some of the lower parts of the Daintree catchment but fortunately these pest species have not been discovered in Cape Tribulation streams as yet. Pig damage is evident in most of the streams of the region and cane toad tadpoles are present in some of the slower flowing Cape Tribulation streams intermittently. The impact of these pests on the aquatic fauna of the region is not well understood. A general lack of scientific knowledge of stream ecology including the composition of the fish fauna in the northern part of the Wet Tropics remains a threat to identifying which streams warrant special protection.

Preliminary studies are revealing some hidden treasures, and further research is required to appreciate and manage these special aquatic ecosystems.

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 Freshwater Moray Eel courtesy of B. Ebner

Freshwater Moray Eel courtesy of B. Ebner

 Rainbow FIsh courtesy of B Ebner

Rainbow FIsh courtesy of B Ebner

The freshwater fishes of this region face numerous threats. There are alien fish species (e.g. guppies) in some of the lower parts of the Daintree catchment but fortunately these pest species have not been discovered in Cape Tribulation streams as yet. Pig damage is evident in most of the streams of the region and cane toad tadpoles are present in some of the slower flowing Cape Tribulation streams intermittently. The impact of these pests on the aquatic fauna of the region is not well understood. A general lack of scientific knowledge of stream ecology including the composition of the fish fauna in the northern part of the Wet Tropics remains a threat to identifying which streams warrant special protection.

Preliminary studies are revealing some hidden treasures, and further research is required to appreciate and manage these special aquatic ecosystems