A fossilized sample of thousand-year-old parrot dung has revealed a previously unknown ecological relationship that could help save a threatened parasitic plant from extinction.
Yup, conservation science is sometimes weird.
The plant in question is called Dactylanthus taylorii (aka wood rose or Hades flower). A parasitic plant that only grows on the roots of about 30 types of trees in New Zealand, the wood rose is now endangered in its native country due to habitat loss, consumption by invasive species such as possums and pigs, and its rather limited number of pollination options. The species, which today exists in just 4 percent of its historic range, is only currently pollinated by the New Zealand lesser short-tailed bat (Mystacina tuberculata), a ground-foraging species which itself has lost 70 percent of its former range.
But here's the thing: according to new research published October 1 in Conservation Biology, the habitat for the wood rose once overlapped with that of another species, the now-critically endangered flightless parrot known as the kakapo (Strigops habroptila). The kakapo, which today numbers just 125 birds, used to be quite common on the country's two main islands before humans arrived, but now it only exists in tightly monitored populations on a few remote New Zealand islands. Researchers from the Australian Center for Ancient DNA at the University of Adelaide, Landcare Research and the New Zealand Department of Conservation (DOC) examined some fossilized kakapo dung (known as coprolites) that had been found on New Zealand's South Island, where both species historically existed. The coprolites contained 8.9 percent Dactylanthus pollen and spores, suggesting the two species not only coexisted but that the kakapo once served as a primary pollinator for the wood rose.
This new knowledge may help inform conservation efforts in the future. "Coprolites are one of the only ways to reconstruct important pre-human ecological relationships, such as pollination and seed dispersal, which must be restored to conserve these species over the long term," lead author Jamie Wood, a researcher at Landcare, said in a prepared statement.
The possible relationship is already being put to the test. Earlier this year eight kakapos were moved to New Zealand's Little Barrier Island, which also happens to be one of the few remaining habitats for the wood rose. According to the researchers, this could be the first time these two species have shared the same habitat in the past century. The DOC will now use camera traps to see if any of the kakapos on Little Barrier Island are pollinating the wood rose, attracted to the flower by its abundant, sweet-smelling nectar. This nectar—released during the plant's brief above-ground flowering phase, which occurs between February and April—also attracts possums, rats and other invasive species that eat the plants without serving as pollinators. This DOC time-lapse photo shows the artichoke-like Dactylanthus flowers opening and drenching the surrounding forest floor with nectar:
By the way, the term "wood rose" is actually a bit of a misnomer. The parasitic plant sucks nutrients from the roots that it surrounds, causing the roots to deform into shapes that resemble flowers carved out of wood. These "roses" are often dug up and sold to collectors, which is another reason why the plant is endangered today.
Photo: Sirocco, the world-famous kakapo. Courtesy of the New Zealand Department of Conservation, via Flickr