A native bat has been detected in urban West Auckland for the first time in 15 years.
The long-tailed bat, about the size of a thumb and weighing as little eight grams, is the more common of the two native bat species.
The senior biodiversity adviser for Auckland Council Ben Paris said the bats had become endangered due to attacks from cats, stoats and rats, as well as through destruction of their habitat.
Mr Paris said echo-location microphones picked up the bats' clicks and calls around Opanuku Stream in Henderson.
He said it was an exciting discovery, which showed the rejuvenation of urban streams could attract the tiny mammal back to the area.
"The stream restoration work has been a long time coming and all that stream restoration means that the bush is healthier, the stream is healthier and therefore has more insects for these little bats to fly around. So I think the more stream restoration we can do, the better it is for our urban bat," he said.
The council offers echo-location gear for hire to help people detect bats in their backyard.