Nature & biodiversity
The Waitaki District is well known for its wildlife, including kororā (little blue penguins), hoiho (yellow-eyed penguins) and the Otago shag. Fur seals lounge on rocky shores and native fish wriggle through the braided river systems. Together the local plant, insect and animal species add to the distinct charm of this geopark.
Braided rivers are one of the distinctive features of Te Waipounamu (the South Island). These rivers are rare world-wide, being limited to places with high rates of tectonic uplift, fragile shattered geology and high rainfall. The wide ‘barren’ beds of shingle that flood and readily change course provide habitat for a range of unique species that have evolved to exploit this productive aquatic environment. The Waitaki lowland longjaw galaxid fish (Galaxias cobitinis) has adapted to the floods and dries of braided channels by wriggling down into the shingle.
Lower Waitaki River is home to New Zealand’s largest breeding colony of the nationally endangered tarapiroe or black fronted tern (Chlidonias albostriatus). These birds are colonial breeders that lay their camouflaged eggs among the river stones on islands within the braided rivers. Their evolution within this dynamic river environment has, to a limited extent, preadapted them to the threats they face from exotic pests, which struggle to access their stony islands detached by fast-flowing channels.
The Waitaki River and its tributaries are also important habitat for the nationally vulnerable ngutu pare or wrybill (Anarhynchus frontalis), the only bird in the world with a bill that is curved to the right. As with tarapiroe, ngutu pare breed exclusively on braided river beds, but as monogamous pairs rather than in colonies. The curved bill allows the ngutu pare to reach insect larve under rounded riverbed stones. At all stages of their life the birds are highly mysterious and blend with the greywacke shingles of the riverbed by freezing when distressed. Although difficult to spot, this behaviour makes these small birds much easier to approach than most New Zealand wading birds.