Rare Haleakala Silversword Threatened by Climate Change

Posted on January 16, 2013

Biologists say the Haleakala silversword plant was under threat in the early 1900s from being eaten by animals and picked by visitors. The rare plant recovered, but has now entered a period of climate-related decline. The amazing plant grows for 20 to 90 years before the single reproductive event at the end of its life. During the reproductive period, the silversword grows a large inflorescence with as many as 600 flower heads. This inflorescence can reach six feet in height.

The silversword (Argyroxyphium sandwicense macrocephalum) grows only on a single volcano summit in Hawaii. It is viewed by 1 million visitors annually at Haleakala National Park. Researchers warn the plant faces a bleak outlook if climate trends continue.

Paul Krushelnycky, a biologist with the University of Hawai'i at Mānoa, College of Tropical Agriculture and Human Resources, and principal investigator for the project, said in a statement, "The silversword example foreshadows trouble for diversity in other biological hotspots, and it also illustrates how even well-protected and relatively abundant species may succumb to climate-induced stresses."

USGS Director Marcia McNutt says, "Despite the successful efforts of the National Park Service to protect this very special plant from local disturbance from humans and introduced species, we now fear that these actions alone may be insufficient to secure this plant's future. No part of our planet is immune from the impacts of climate change."

More from Science Space & Robots