An area of native bush in Wellington is being ravaged by those creating illegal mountain biking tracks, damaging the only home for an incredibly rare native snail.
As well as the critically endangered potamopyrgus oppidanus snail, native birds such as kererū, kākāriki and kārearea live at Te Ahumairangi Hill, formerly Tinakori Hill.
It's an area popular with runners and mountain bikers, but there are concerns illegal tracks are ruining the sensitive ecosystem.
"The felling of mature trees that are 20-50 years old, and the subsequent removal of undergrowth is significant and irreversible over the short term," a spokesperson for a local conservation told 1 NEWS.
Te Ahumairangi Hill Ecological Restoration is trying to protect the bush, fearing the tiny rare snail has "fallen through the gaps of protections".
"As a tiny overlooked freshwater invertebrate, on unprotected land, outside of the Wildlife Act, it is perhaps our most perfect local example of vulnerable taonga that has been failed to be adequately protected, yet is under 1km from the Beehive."
The spokesperson says they were "surprised and devastated" to come across the latest damage.
Hundreds of saplings had been uprooted and mature native trees were cut down in the precious bush.
Pukehīnau Lambton Ward Councillor Tamatha Paul told 1 NEWS the council has been working together with the conservation group to try and protect the area and its biodiversity.
"Community members, volunteers and residents have continued to plant natives within the area, including along the illegal mountain biking tracks," she says.
"It is horrifying to see at least 600 mature trees being ripped out of the ground."
There are four authorised mountain biking tracks in the bush and the council works with the local clubs to help educate bikers.
"The Wellington MTB Club has spoken repeatedly regarding the issue of unauthorised trail building, and are very frustrated about this continuing illegal activity," Ms Paul says.
"This has been a tragedy to all members of the community."
The club also helped replant hundreds of native trees in one damaged section last year, the Te Ahumairangi Hill Ecological Restoration spokesperson says.
To try and prevent more damage, park rangers are patrolling the area. There's signage and fences closing off illegal travels, with cameras also being installed to try and catch the culprits.
If caught, people face being trespassed and prosecuted by the council.
Work is also underway to allow park rangers to issue fines under the Reserves Act, for people caught damaging vegetation.
"Te Ahumairangi has an abundance of sensitive rare habitats that need to be cherished," the protection group spokesperson says.
"On this broader scale, now is the time to protect biodiversity, at community, regional, national and global levels, because it is one of the most important ways we can keep our citizens healthy and restore the planet.
"We feel we need to be more proactive and face the big challenges of colliding biodiversity, freshwater and climate crisis right here in our backyard, on Te Ahumairangi Hill."
Anyone who sees suspicious behaviour or damage is asked to contact the Wellington City Council or (04) 499 4444, or by using the Fix-It app.
The indigenous rare snail is tiny, only around 3mm long, and has only been found on Te Ahumairangi Hill.
It's recognised as critically endangered and in population decline.