Forest and Bird says multiple endangered species have been saved thanks to the decision to axe plans of a monorail through Fiordland.

Conservation Minister Nick Smith has announced it would not be environmentally or economically viable.

Forest and Bird's Otago Southland field officer Sue Maturin says they're thrilled with the decision, and plans for a 29 kilometre monorail through a World Heritage Area were unrealistic from the beginning.

"It should have been the decision he should have made months and months ago, we're surprised its taken so long to reach that conclusion because it does have such outstanding conservation values."