Speckled, pencil-thin and sporting an underbite: the lowland longjaw galaxias is New Zealand’s rarest freshwater fish species. With just seven known populations, this species is considered nationally endangered. Join producer Karthic SS at a spring-fed stream in the wild Mackenzie Basin to meet the tiny fish, hear from a researcher studying trout-proof barriers, and chat to a ranger who for 20 years has cared for the little fish he calls 'Jaws'.

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Guests:

• Dean Nelson, Senior Ranger, Biodiversity, Department of Conservation
• Martha Jolly, PhD candidate, University of Canterbury

Learn more:

• Otago farmers are looking out for another species of rare non-migratory galaxiid.
• In Auckland’s Lake Rototoa, introduced perch are the problem for the native kākahi.
• Karthic produces the Tune Into Nature podcast about New Zealand’s unique wildlife.

Go to this episode on rnz.co.nz for more details