Sleepy cod were initially observed in the Thomson Fish communities were monitored under the Lake River and over the last six years this translocated Eyre Basin Rivers Assessment program in 53 species has spread throughout waterholes and waterholes across the Basin between 2011 and ephemeral streams of the Cooper Creek and 2016. Fish communities are generally in good downstream to Coongie Lakes in South Australia. condition across the Basin (Figure 3), with riverine Previous translocations of sleepy cod in Australia environments supporting 19 native fish species have resulted in rapid colonisation of the receiving including Lake Eyre yellow belly, Barcoo grunter, environment. This has resulted in a decline in three catfish species, Cooper Creek tandan, Welch’s species with similar niche requirements and it is grunter, desert goby and Finke goby. currently unknown how this species will affect the Although fish communities in the Basin are native fish, riverine and wetland habitats of the generally in good condition, work conducted under Basin. the Lake Eyre Basin Rivers Assessment program Goldfish were found in relatively high numbers has identified three exotic and translocated species throughout the Cooper catchment following the as a threat: goldfish, gambusia and sleepy cod. 20102011 wet season. Goldfish numbers fell A rapid expansion in the range of sleepy cod, a rapidly during the following drought. translocated native fish that is foreign to the Basin, Gambusia were found in low numbers in has occurred in the Cooper Creek catchment. This waterholes monitored by the Lake Eyre Basin large predatory species poses a serious conservation Rivers Assessment program. Their presence risk to native species. Before 2008, sleepy cod were appears to have few effects on native riverine fish not found in the Lake Eyre Basin. communities but does pose a potential threat to endemic fish of nearby spring habitats if these are infrequently connected to riverine habitats.
Fish communities were monitored under the Lake Eyre Basin Rivers Assessment program in 53 waterholes across the Basin between 2011 and 2016. Fish communities are generally in good condition across the Basin (Figure 3), with riverine environments supporting 19 native fish species including Lake Eyre yellow belly, Barcoo grunter, three catfish species, Cooper Creek tandan, Welch’s grunter, desert goby and Finke goby. Although fish communities in the Basin are generally in good condition, work conducted under the Lake Eyre Basin Rivers Assessment program has identified three exotic and translocated species as a threat: goldfish, gambusia and sleepy cod. A rapid expansion in the range of sleepy cod, a translocated native fish that is foreign to the Basin, has occurred in the Cooper Creek catchment. This large predatory species poses a serious conservation risk to native species. Before 2008, sleepy cod were not found in the Lake Eyre Basin. Sleepy cod were initially observed in the Thomson River and over the last six years this translocated species has spread throughout waterholes and ephemeral streams of the Cooper Creek and downstream to Coongie Lakes in South Australia. Previous translocations of sleepy cod in Australia have resulted in rapid colonisation of the receiving environment. This has resulted in a decline in species with similar niche requirements and it is currently unknown how this species will affect the native fish, riverine and wetland habitats of the Basin. Goldfish were found in relatively high numbers throughout the Cooper catchment following the 20102011 wet season. Goldfish numbers fell rapidly during the following drought. Gambusia were found in low numbers in waterholes monitored by the Lake Eyre Basin Rivers Assessment program. Their presence appears to have few effects on native riverine fish communities but does pose a potential threat to endemic fish of nearby spring habitats if these are infrequently connected to riverine habitats.
state-basin-condition-assessment-2016-summary.docx