Trounson Kauri Park is has been managed as a mainland island since 1995. The goal is to  restore the former richness of native biodiversity this forest once boasted, and to let visitors enjoy a glimpse of what pristine kauri forests were once like.

It is home to several threatened species, such as North Island brown kiwi, kūkupa (New Zealand pigeon), pekapeka (bats) and kauri snails. It has the highest-density of North Island brown kiwi populations in Northland, under threat from a northward-advancing ferret population.

It also incorporates a magnificent dense stand of kauri that has long been recognised as one of the best examples in the country.

Threats

Introduced pests and predators have had a devastating impact on Northland's unique habitat types. Many native and endemic species are now extinct, some have been shifted to predator-free islands for a chance of survival, while others are still trying to hold on in their modified environment.

These introduced pests pose a particular threat to the recovery and restoration of Trounson Kauri Park's ecosystem: possums, rodents, mustelids (ferrets, stoats and weasels), cats and dogs.

Most of the forest was gifted to the Crown by James Trounson, an early settler, and officially opened in 1921.