Lake Ototoa is a large deep lake located amongst the sand dunes of the South Kaipara Heads, which was formed when an advancing sand dune blocked a stream valley. It has the best water quality of the lakes monitored by the ARC.

The lake supports a variety of native plants within the lake and around its margin, and is home to several native fish that are uncommon in the Auckland region. Lake Ototoa is also a significant rainbow and brown trout fishery.

Four years ago, perch, an introduced fish from the Northern Hemisphere, was illegally released into the Lake. Perch are voracious predators and recent declines in the populations of native dwarf inanga, common bullies and koura are a consequence of perch predation.

Experts predict that some of these species may be wiped out from Lake Ototoa if the population of perch is not dramatically reduced. Perch also threaten the trout fishery with recent catches being of smaller size and lower quality.Recent decline in native fish have mirrored increases in perch in Lake Otatoa.

The DOC and ARC staff told the related information to the visted Chinese.

They also had a BBQ there, walked along the lake track, fished the pest fishes, and visited alpacas.

They had a very good time there.