The intricate ecosystem of streams
Streams provide habitat and food for hundreds of plants and animals – from tiny algae to 100-year-old longfin eels – and have delicately balanced ecosystems.
If healthy, the banks of the streams themselves (riparian areas) improve water quality, provide habitat and shelter for fish, and lower the water temperature. Riparian areas also filter out sediment and pollutants and increase bird and insect life.
The diversity of small macroinvertebrates such as insects, worms, and snails found in streams tell us a lot about the health of our freshwater ecosystems.
Rare species in Wellington streams
Wellington streams are home to 16 native fish species, including:
- Giant kōkopu (At risk: Declining, Vulnerable)
- Longfin eel /tuna kuwharuwharu (At risk: Declining)
- Shortjaw kōkopu (Threatened: Nationally vulnerable, Endangered)
There is a lot to learn about fish in New Zealand. For instance, that whitebait is made up of five separate native species, four of which are in serious trouble.
Streams above and beneath our streets
Our streams in Wellington can be divided into two groups – rural or urban.
More mysterious streams are the 'lost' streams that lie beneath the city. Many streams in our city were enclosed in pipes to make way for infrastructure above. These are known as ‘lost’ streams or piped streams. Though we can't see them, they are still an important home to native flora and fauna.
Our rural streams in Wellington include Karori, Makara, Ohariu, Opau Streams, Oteranga Stream.
Urban streams include Owhiro, Kaiwharawhara, Ngauranga Stream, and the Porirua Stream system.
Stream monitoring report (3,611KB PDF)
Piped stream monitoring report (11,064KB PDF)
Main threats to freshwater fish
Streams are both homes and highways for fish. Nearly all of New Zealand’s freshwater fish species migrate between freshwater and the sea during their lives as an important part of their breeding cycle.
The loss, damaging, or blocking of streams – whether rural, urban, or piped– risks the extinction of fish in that stream. Sometimes this is in the form of dams and culverts.
Pest and introduced fish species threaten our indigenous flora and fauna in waterways, lakes and wetlands. Perch and trout, for example, can reduce water quality and prey on native fish and insects.
Storm drains lead to our streams
Many Wellingtonians don't realise that our stormwater drains flow into our streams and sea.
Stormwater – Preventing pollution and flooding
You can help
From keeping chemicals out of our stormwater drains to washing your car on the grass, you can help.
What you can do for the environment – Keep our water clean
It's illegal to fish in Wellington's public waterways and streams. Report any illegal activity to protect our native wildlife.