The Crested Grebe is a native bird species which is fully protected, rare and threatened. There are only 250-300 breeding pairs living in NZ, all in the South Island and mostly in the Southern Lakes region.
The origin of Grebes goes back at least 40 million years. They’re most closely related to albatross and penguins and their legs are set well back on their body. This is a problem for the Grebes; it means they can barely walk on land, making it hard for them to escape predators during the breeding season. This is why they tend to build their nests on floating platforms on lake weed and debris usually attached to submerged branches and tree roots close to the shore.
Retired Wanaka Zoologist, John Darby is utilising broken swimming pool noodles to build floating nest platforms for them to breed on. As an antipredator strategy it works well as the grebes fall off the nest straight into the water if they hear something approaching. The Grebes characteristically carry their chicks on their backs, for the first 2-3 weeks after hatching.
The first artificial platform was built in about 2013 and installed at the Wanaka lakefront and overnight it attracted a pair of Grebes. After a bit of trial and error with different designs and materials the most reliable method was established. When the Wanaka lakefront is particularly windy there have been some problems with the stability of the platforms.
The Wanaka lakefront breeding programme is proving successful. It started with a single pair of grebes and now there are at least 17 breeding pairs. To date 81 chicks have been fledged.
The platforms are located within the marina area on the Wanaka lakefront, with some being attached to the marina and some moored between there and the shore. There are weekly updates in the Grebe diary in the Wanaka Sun publication each week.

http://www.odt.co.nz/news/queenstown-lakes/323279/grebes-make-instant-use-nesting-platforms

http://www.doc.govt.nz/news/media-releases/2015/lake-wanaka-grebes-thrive-with-a-bit-of-help/