Human activities & development
Cattle on Cass riverbed
Many activities associated with land development have adverse effects on the habitats and populations of native plants and wildlife:
- Water abstraction and damming for hydroelectric development alter river flows and developing braids and islands, reducing the amount and quality of braided river and wetland habitat.
- River engineering works, including willow plantings, also alter the way in
which river channels form and develop
over time.
Ohau C power station
- Wetlands are drained for pastoral development.
- Pasture grasses displace native plant communities and other introduced plants.
- Livestock graze or trample native plants in riverbeds and remaining nearby wetlands. Irrigation and fertilisation of pastoral land can result in nutrient run-off into waterways and reduced water quality.
Even recreational activities can have adverse impacts; for example:
4WD vehicles, Hopkins/Te Awa Āruhe
riverbed
- Uncontrolled dogs can scare birds away from their nests, causing eggs and chicks to die.
- Four-wheel drive vehicles used in riverbeds can squash fragile plants and crush the eggs and chicks of ground-nesting birds.
Many of these human activities and land use changes expose braided river ecosystems to invasion by exotic weeds.
Contacts
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Twizel Area Office
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Phone:
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+64 3 435 0802
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Fax:
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+64 3 435 0852
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Email:
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TwizelAO@doc.govt.nz
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Address:
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Wairepo Road
Twizel 7901
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Postal Address:
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Private Bag
Twizel 7944
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