Biodiversity or biological diversity, means the variability among living organisms from all sources, including land, marine and freshwater ecosystems and the ecological complexes of which they are a part. This includes diversity within species (including genetic diversity), between species and of ecosystems (Aotearoa New Zealand Biodiversity Strategy 2020).

Biodiversity is fundamental to life, and central to the environmental services, such as food and fresh water, that people and other organisms depend on. Biodiversity and climate change are intrinsically linked through ecosystem services that regulate the global climate. The wellbeing of people and biodiversity are deeply intertwined, with strong interlinkages important to consider, particularly in a changing climate.

While New Zealand’s indigenous biodiversity shapes and sustains society, it is declining. Biodiversity loss is a global issue and provides one of the greatest challenges currently faced by the world community, including New Zealand.

Land transport is directly and/or indirectly linked to each of the five key pressures of biodiversity decline that have been identified globally: land-use change, pollution, climate change, natural resource use and invasive pest species. Land transport’s construction, placement in landscape, maintenance and operational activities can all negatively affect biodiversity. Ecological effects of land transport may include:

  • direct and indirect mortality of animals
  • loss and degradation of indigenous vegetation, ecosystems and/or habitat for native fauna
  • loss of ecological connectivity in the landscape, including for native fish
  • alteration of animal behaviour (eg disturbance, avoidance)
  • facilitating pest establishment and providing a corridor by which pests disperse. 

Transport corridors may also have positive effects where they act as refuges in landscapes where little native habitat remains. Indigenous biodiversity here is likely to have disproportionate value because they are all that is left in an otherwise depauperate landscape (one which is lacking in numbers or variety of indigenous species).

A challenge for Waka Kotahi is achieving our core function of investing in land transport activities, managing the state highway network, and providing access to land transport while not adversely affecting indigenous biodiversity. Biodiversity is complex, dynamic and varied and, for Waka Kotahi, biodiversity matters are diverse and expansive,

We are committed to minimising the negative effects of our activities on ecological features, and to protect and, where possible, enhance biodiversity on Waka Kotahi land. There are opportunities for land transport corridors to support native biodiversity, with road verges potentially playing an important role either because of the species and/or habitat they support or the environmental function they perform.

Our policy

Our policy on biodiversity can be found in:



* Note: our Fish passage guidance for state highways is currently out of date. We are in the process of updating it, along with a new policy and specification. In the meantime, refer to and follow:



Case studies

These case studies to demonstrate how ecological principles and practices have been applied to individual transportation projects, as a way of sharing the lessons learnt from individual projects.


Te Ahu a Turanga moth relocation – February 2021

Takitimu North Link: Mokomoko (indigenous lizards) relocated at Mauao

Further information

For further information contact