In European times it was part of an inland waterway that carried timber and settlers between Hokitika and Ross until the building of the railway.

The Hokitika River then changed course, shifting to its current mouth 8 km north and leaving behind a lake now fed by a series of small creeks.

Royal spoonbills, grey ducks, and fernbirds can occasionally be seen; white herons (kōtuku) can be found seasonally around the shore or more commonly in the streams entering or leaving the lake.

[6] There are still small populations of shortfin eels and īnanga in Mahinapua, which coexist with introduced perch, tench, and brown bullhead catfish.

[6] Luckily rudd have not colonised the lake, but it contains invasive white waterlily (Nymphaea alba) and Cape pondweed (Aponogeton distachyos).

The piled-up bodies of chiefs on the lake's foreshore gave the battle its name: Tāwiri a Te Makō (heap of sharks).

[7] The site of the battle is regarded as a wāhi tapu (sacred place) and local Ngāi Tahu will not harvest food from the lake or swim in it.

[7] When the tide is high, it is possible to travel by small boat from the lake down Mahināpua Creek to Hokitika, a fact of great importance to Pākehā settlement before the building of a road.

From 1865 boats were used to carry people and freight from Hokitika up the creek, crossing the lake and unloading at a portage landing beside Ruatapu, and continuing down a lagoon to Ross.