Herbarium specimens offer a rare glimpse into the historical hunt for Fiordland kākāpō

Botany curator Leon Perrie and researcher Lara Shepherd recently visited the Allan Herbarium in Lincoln to examine its speargrass/taramea (Aciphylla) specimens as part of their ongoing taxonomic research into these plants. The herbarium’s historical specimens offer valuable insights that enhance our recent collections, particularly around morphological diversity and species distributions. One box of specimens caught their attention – the leaves were so tattered and frayed, they looked as if they’d survived a run-in with a lawnmower! Intrigued, Lara dug deeper into the story behind the battered specimens.

Herbarium collections typically aim to showcase pristine examples, with clean foliage and minimal insect or animal damage – specimens that best represent a species’ typical form. So, finding a number of specimens in such poor condition was a surprise – until we read the labels.

These leaves had been chewed – by kākāpō. That detail alone was remarkable. Kākāpō, large flightless parrots, are one of Aotearoa’s rarest species. But what made the specimens truly significant was their origin. Collected from Fiordland in the 1970s, they hail from a pivotal moment in conservation history, when the species was perched precariously on the edge of extinction and researchers were racing against time to save them.

Searching for kākāpō

By the 1950s, kākāpō were only known from remote areas of Fiordland, having been heavily impacted by introduced predators. In response, between 1949 and 1977, the newly formed New Zealand Wildlife Service embarked on extensive search efforts. As well as listening for calls, looking for droppings, feathers and their distinctive track-and-bowl systems, wildlife workers also searched for kākāpō feeding sign.

Kākāpō are herbivores and some of their feeding sign can be confused with those of deer, rats and possums. However, kākāpō “chews” are a unique sign of the species — these are the fibrous remnants left behind after kākāpō crush the leaf tips of certain tough plants, such as Aciphylla takahea, to extract nutrients. These telltale fibres can remain on the plant as a distinctive signature of kākāpō presence for weeks or months.

All of the ‘chewed’ speargrass specimens at the Allan Herbarium were collected during searches in the field for kākāpō or from within Wildlife Service aviaries in Fiordland, where captured kākāpō were housed.

Over the 28 years of searching, only 24 birds were found in Fiordland, and all were male. Some of these birds were brought into captivity, but most died within a few months. It appeared kākāpō were heading for extinction.

Saving a species

Then, in 1977, a large population of kākāpō was found in southern Rakiura Stewart Island, this time including females. It was a turning point for the species. Through the 1980s and 1990s, conservationists made the bold decision to relocate the entire Rakiura population to three predator-free offshore sanctuaries. Added to these birds was Richard Henry – the lone Fiordland male who defied the odds. Discovered in 1975, he famously sired three chicks with a Rakiura female, ensuring that his unique Fiordland genes boosted the genetic diversity of the species. The last remaining kākāpō in Fiordland were left to die out in the 1980s.

The speargrass specimens are a poignant reminder of how close we came to losing a taonga species – a recurring theme in the story of Aotearoa’s wildlife.

Further reading

• Aspinell, J. 1976. Searching for the rare kakapo in Fiordland. Forest and Bird 202: 2.
• Atkinson, I.A.E.; Merton, D.V. 2006. Habitat and diet of kakapo (Strigops habroptilis) in the Esperance Valley, Fiordland, New Zealand. Notornis 53(1): 37-54.
• Butler, D.J. 2006. The habitat, food and feeding ecology of kakapo in Fiordland: a synopsis from the unpublished MSc thesis of Richard Gray. Notornis 53(1): 55-79.