A proposal to allow mountain bikers on Rangitoto and Motutapu Islands has angered an Auckland conservation group which says it puts endangered birds at risk.
The Department of Conservation wants to open up roads and and some tracks on both islands year-round to cyclists for a three-year trial period.
In a draft 10-year management plan for Auckland, DoC says both islands in the Hauraki Gulf offer up to 40km of in-demand off-road cycling tracks.
Bikes would be available for hire only on the island for groups limited to eight, with or without a guide.
But Christine Fletcher, chair of the Motutapu Restoration Trust and an Auckland councillor, says the idea is a revenue-gathering venture that would be detrimental to the environment.
"We've invested 20 years in creating the habitat on Motutapu and Rangitoto in order that we can re-introduce very rare species - saddlebacks, Coromandel kiwi, takahae.
"I think it's just a foolish idea by a desperate department."
Public comment on the plan is open until 15 March.