Former Chief Scientist for the Environmental Protection Authority Dr Jacqueline Rowarth agrees with Dr Mike Joy that New Zealand's freshwater fish species are under threat.

In a study published yesterday, Victoria University's Joy and colleagues compared land use changes and more than 20,000 freshwater fish records since 1970, the results of which showed more than three quarters of 25 analysed species were in decline.

Rowarth told The Country's Jamie Mackay that Joy is right to be concerned about certain species being depleted.

Listen below:

"Dr Joy has absolutely said it is insane that we are eating the young of some of our endangered fish and I absolutely agree with him. He's also made the point about some of the eels they're allowing to be caught, the longfinned eel, and yet they're endangered."


Rowath is also concerned about the Productivity Commission report's recommendation that 20 per cent of sheep and beef farming land be given over to forestry in an attempt to reduce emissions - a move she believes is not fiscally viable.

"Forestry implies you're going to harvest it at some point and actually the land they're talking about is not harvestable. They're saying it's remote – well that means you can't actually harvest it ... it costs too much."

Mackay asks Rowarth if she would consider returning to academia, but she says there isn't a demand due to lack of numbers in agricultural admissions which is "pretty sad."

"And why are the numbers down? Well because children of farmers are feeling that maybe they don't want to endure ...the same sort of life as their parents have and part of the parent's problems are the environmental lobby, the uncertainty of the ETS [and] the ongoing concerns about what the regional councils might do."