Te Kūwaha and Māori

Currently, the most reliable method to estimate the age of tuna is by examination of their otoliths or "ear bones"

Once eels become migrants (also known as tuna heke or tuna whakaheke) they stop feeding, and progressively develop the external features that clearly distinguish them from 'feeders'.

All species of freshwater tuna spawn at sea, although the spawning grounds of only four species are known with certainty worldwide.

New Zealand's first eel farm was established in 1971. Despite other farms opening in later years, no eel farms remained by the start of the 1980s.

Easing the resource consent process

Glass eels (about 5.5 to 7.0 cm) arrive in fresh water during spring, especially during September and October, although they may be present from July to December.

Instream barriers and diversions alter the natural flow of rivers, streams, and lakes.

Once in freshwater, glass eels develop into darker pigmented juvenile eels known as elvers.

Some simple steps to minimise the effects of wastewater on water quality and mahinga kai.

A number of individuals, organisations and hapū have contributed to the development of Ngā Waihotanga Iho.

Traditionally, tangata whenua have collected information about estuaries to monitor resources, such as kaimoana, and to make decisions about conservation measures, such as rähui. Increasingly, tangata whenua are using scientific tools to help monitor their natural resources and Ngä Waihotanga Iho provides a science perspective for talking about environmental issues and concerns related to estuaries.

Through the Te Wai Māori fund Ngā Repo o Maniapoto is a collaborative project between NIWA and the Maniapoto Māori Trust Board (MMTB) Whanake Taiao team that looks to develop an inventory of repo and puna (springs) for the Maniapoto rohe.