Levels of suspended sediment in Lake Waikare are high. Sediment enters the lake from the adjoining land and rivers, and is stirred up by wind and wave action, and the pest fish koi carp. In the wetland, sediment comes from a number of sources, including from Lake Waikare, the Maramarua River and adjacent land.
A 2012 report gave catchment management with farm-scale actions the top-ranked mitigation option. As a result Waikato Regional Council has, through its 2015-2025 Long Term Plan, committed to developing a catchment management plan, which will set out measures to best address sediment sources impacting on the wetland. It will also help deal with the wider range of issues in the catchment, including the lake’s water quality and biodiversity.
Wetlands and riverine lakes, as Lake Waikare can be classified, contain a diverse range of plants and animals and are home to many rare and threatened species. They are some of our rarest and most at-risk ecosystems.
Some of the (threatened) species commonly found include the Australasian bittern, banded rail, grey duck, grey teal, marsh crake, New Zealand dabchick, New Zealand shoveler and spotless crake. Brown teal were once present, but are now believed to be regionally extinct.
Many birds move between lakes and wetlands as food and nesting requirements change with seasonal variations in water levels. The large lakes are especially important as a refuge for moulting birds that are growing new flight feathers.
Native fish found in the lakes include common smelt, grey mullet, whitebait and longfinned and shortfinned eel. The majority of these species move between the swamps, lakes, river and the sea, depending on their particular life cycles.
Waikato Regional Council is working with a group of key stakeholders, including the Lower Waikato Catchment Committee, the Department of Conservation, Fish & Game New Zealand, Waikato District Council, landowners and local iwi representatives to better understand the goals and aspirations people have for Lake Waikare and the Whangamarino Wetland. Understanding the work that’s already being done in the sub-catchments is also an important part of the process to help improve the health of these natural assets.
This information will be used to develop the CMP, which will be drafted by our council under the direction of an independent project manager and with support from a technical team. Key stakeholders, including local landowners and iwi, will be consulted throughout the process and will be enabled to provide feedback.