Relating to the environment

A bat detector in use on the Cambridge section of the Waikato Expressway.

The team constructing the Waikato Expressway learn about the environment around the highway. Then they take steps to protect native bats and fish, and plant more trees.

  • Read on for the full story: The bat detectors

About 365,000 plants were planted along the Cambridge section of the Waikato Expressway. This helps to compensate for trees that were removed  during construction.
Trees planted include oak, horse chestnut, poplar and native species Kahikatea and Totara.

The new trees will provide shelter and food for long-tailed bats. Fast growing poplar and slower growing oak trees planted in the Karapiro Gully will eventually provide homes for the bats, where they can sleep and breed. Native trees attract the insects that bats feed on.

Students grow highway oaks
Find out how local school student grew trees for the project

Bat facts

  • New Zealand has two species of bat. The long-tailed bat is more common than the lesser short-tailed bat.
  • A third species, the greater short-tailed bat, is believed to have gone extinct in the 1960s.
  • Long-tailed bats have a body the size of a grown-up person’s thumb.
  • They have a top speed of 60 km/h.
  • Bats are New Zealand’s only land-based mammals. They give birth to live young, which can fly after 4 or 5 weeks.

Bigger home for fish

Ecologists went to look for wildlife before work began on the Rangiriri section of the Waikato Expressway. They found a large population of black mudfish. This species is at risk due to the loss of its home as the wetlands of the Waikato were drained over the years.

It’s a curious animal. Black mudfish can survive out of water, sometimes for several months. They keep moist by burrowing into mud or leaf litter until they can return to water.

In this case, the black mudfish were moved to specialised tanks at the University of Waikato while their habitat was made bigger. The team added native plants and a winding stream channel, plus shallower wetland areas. The fish are now back home.

Rare black mudfish return home

Black mudfish (information from the Department of Conservation)