SANBI

Rationale

Galaxias sp. nov. ‘ Gouritz’ is a recently identified lineage of the G. zebratus complex and is being assessed for the first time. Since its discovery in 2009, two major surveys have been conducted in the Gouritz River System and this lineage has been found to be restricted to the Weyers River sub-catchment. It is currently known from only one location and has an estimated area of occupancy (AOO) of 16 km². Potential invasion of the Weyers River by non-native fishes from the mainstem Gouritz poses the greatest threat to this lineage and if it were to occur, could result in this species being rapidly pushed into Critically Endangered or Extinct. Weirs and potential increase in water abstraction from the mountain tributaries of the Weyers represent another major potential threat. The species is thus assessed as Vulnerable D2. Further surveys are required to establish the status of population sizes and distribution in the Upper Weyers and its tributaries.

Distribution

Galaxias sp. nov. ‘Gouritz’ has only been recorded from the Weyers subcatchment in the Gouritz River System. Given the recent extensive surveys across the Gouritz system, the lineage appears to be restricted to the Weyers subcatchment.

Habitat View more ecological information

Population trend

Trend

Galaxias sp. nov. ‘Gouritz’ was recorded in very low numbers at all the localities where it was found during surveys conducted in 2009 and 2018. Further surveys of the Upper Weyers and its tributaries are required to establish the distribution and status of the remnant populations of this lineage.

Threats

The potential threat to this lineage is invasion of the Weyers River and its tributaries by non-native fishes from the mainstem Gouritz River. Excessive or complete water abstraction is also a potential future threat due to the projected increase in aridity in the CFE with global climate change.

Uses and trade

This species is not utilised.

Conservation

There is currently no known conservation action for this lineage. Immediate conservation efforts should aim to secure the Weyers sub-catchment from potential invasion by non-native fishes, as well as raising awareness to stakeholders in the Upper Weyers on the need to maintain ecological flow regimes to allow persistence of this lineage.

References

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