Fossilised dung (coprolites1) from kākāpō in a cave in the South Island has revealed an unexpected and hitherto unknown relationship between three of the country’s most unusual threatened species2
- The nocturnal3 flightless kākāpō (Strigops habroptilus)
- A burrowing bat called the New Zealand lesser short-tailed bat (Mystacina tuberculata)
- A rare underground, parasitic plant – the Hades flower (Dactylanthus taylorii)
Researchers from Landcare Research, the Department of Conservation4, the University of New South Wales and the Australian Centre for Ancient DNA5 (University of Adelaide) found that the ancient kākāpō coprolites, identified by DNA analysis, contained large amounts of pollen6 of the rare Hades flower, which lives underground and has no roots or leaves itself.
Birds could once have pollinated the Hades flower
In their research paper, the scientists explain that the range of all three species has shrunk considerably since human settlement, and the present distributions of the Hades flower and the kākāpō no longer overlap (until a recent reunion on Little Barrier). Currently, the forest-floor-foraging lesser short-tailed bat is the only known native7 pollinator8 of the Hades flower, which gives off a musky sweet smell to attract the bat.
However, the findings raise the possibility that birds and other small fauna9 could have once fed on and pollinated the plant. “If confirmed, through experimental work and observations, this finding may inform conservation of the plant. For example, it may be possible to translocate10 D. taylorii (Hades flower) to predator-free offshore islands that lack bats but have thriving populations11 of endemic12 nectar-feeding birds.”
Dr Janet Wilmhurst from Landcare Research says the Hades flower is now restricted to around 4% of its pre-human range, due to forest clearance, predation13 by introduced mammals and a lack of pollinators and seed14 dispersers. Scattered populations only survive in the central North Island and a few offshore islands.
Reunion of kākāpō and Hades flower on Little Barrier
Kākāpō are extinct from mainland New Zealand but have recently been introduced to Little Barrier Island, where the Hades flower still survives. The researchers believe that this reunion of the two species is the first time they have overlapped in a century.
Dr Jamie Wood, lead researcher and also from Landcare Research, says the examination of coprolites can be one of the only ways to reconstruct important pre-human ecological relationships “such as pollination15 and seed dispersal16, which must be restored to conserve these species over the long term”.
Australian Centre for Ancient DNA Director Professor Alan Cooper says the findings show an important example of a tight co-evolutionary relationship between threatened endemic species. The plant and burrowing bat simply represent “the last men standing”.
“The coprolites suggest that kākāpō may have served as pollinators, probably along with other species, which is critical for conservation, and reveal the extent of the ecosystem17 links that have been broken.”
The research was published in the December 2012 edition of Conservation Biology.
Useful link
Read more about our short tail bat's unique relationship with Dactylanthus taylorii in this 2021 article from Predator18 Free NZ.
Related content
Discover more about New Zealand’s native bats and the ongoing conservation efforts to ensure their ongoing survival.
Activity idea
In relation to this article, your students may like to try this Pass the pollen activity in which they act out the process of insect pollination and learn that some flowers offer their pollinators a reward.
- coprolites: Fossilised excrement (also called fossilised dung, faeces or poo). Analysis of coprolites for plant and animal fragments gives scientists information about the diet and environment of ancient animals.
- species: (Abbreviation sp. or spp.) A division used in the Linnean system of classification or taxonomy. A group of living organisms that can interbreed to produce viable offspring.
- nocturnal: Active at night.
- conservation: The protection, preservation and careful management of a species, habitat, artifact or taonga.
- DNA: Deoxyribonucleic acid (DNA) is a molecule that contains the instructions needed for an organism to develop and function. These instructions are stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C) and thymine (T).
- pollen: Dust-like grains that contain male sex cells (gametes) of flowering plants (angiosperms) and cone plants (gymnosperms). Pollen is made on the anthers of flowering plants.
- native: A species that lives naturally in a country, as opposed to species that have been introduced by the activity of humans.
- pollinator: Something that carries pollen from one flower to another.
- fauna: Animals.
- translocation: When plants or animals are transported to a new area to establish a new population or to add genetic diversity to an existing population.
- population: In biology, a population is a group of organisms of a species that live in the same place at a same time and that can interbreed.
- endemic: Native to only one location. For example, species endemic to New Zealand naturally occur only in New Zealand but may have been introduced elsewhere in the world.
- predates: To hunt or seek prey.
- seed: 1. Part of the sexual reproduction of angiosperms (flowering plants) and gymnosperms (cone plants). Contains an embryo and its food store, which creates a new plant when conditions are right. 2. Offspring or progeny.
- pollination: The transfer of pollen grains from the anther to the part of the plant containing the ovules. This process is necessary for fertilisation and reproduction of the plant.
- dispersal: Movement of an organism to a new place. Seeds in plants and spores in ferns and fungi help dispersal by floating on the wind to new habitats. This allows stationary species to colonise new areas.
- ecosystem: An interacting system including the biological, physical, and chemical relationships between a community of organisms and the environment they live in.
- predator: An animal that kills and eats other animals, called its prey.