During the early to mid Miocene period, 14 to 19 million years ago, a vast lake covered much of what is now Central Otago.

Along the shores of Lake Manuherikia, whose remnants are found near present-day St Bathans, lived crocodilians, turtles, and bowerbirds, as well as early relatives of bats, moa and kiwi, and a rich diversity of waterfowl such as ducks and swans.

This lost ecosystem is known today from the famous St Bathans fossil deposits, which preserve one of the world’s richest records of the Miocene and offer a rare window into Aotearoa’s warmer, more subtropical ancient past.

Our newly published research adds another waterfowl species to this remarkable menagerie. It also sheds important new light on the origins of New Zealand’s recently extinct giant, flightless geese of the genus Cnemiornis.

NZ’s long-lost waterfowl

Spanning 5,600 square kilometres, Lake Manuherikia was ten times the size of New Zealand’s Lake Taupo. It was a dynamic habitat that supported a diverse range of waterfowl, including five stiff-tailed ducks, one swan, two shelducks, one dabbling duck and our new goose.

While many of these waterfowl are incredibly........

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