Kīlauea Point National Wildlife Refuge has had a bumper year for ‘A‘o, or Newell’s Shearwater, this year. At least 11 breeding or prospecting pairs of this endangered species were recorded – the highest number ever found on the Refuge.
The ‘A‘o is only found on the Hawaiian islands and Kaua‘i is home to around 90% of the world’s population. Being a true mariner, it spends most of its time out at sea where it roams for thousands of miles, only coming to land during the breeding season which runs from April to November. While the majority of ‘A‘o nest in native habitat in the mountains, the Kīlauea Point population is unique in that the birds are breeding in a coastal area.
The population was initially established during an egg translocation project in the 1980s, when ‘A‘o eggs were brought out of mountain colonies where they were being eaten by introduced predators and put in the nests of ‘U‘au kani (also known as the Wedge-tailed Shearwater, another native shearwater species) to rear. This was undertaken in the hopes of establishing a population in a relatively safe area where they could be actively protected, as the numbers of ‘A‘o were falling rapidly. However while the majority of birds fledged successfully that year, the breeding population on the Refuge has remained small ever since.
In 2007, the Kaua‘i Endangered Seabird Recovery Project, in collaboration with the Refuge, set up a ‘social attraction’ project to try to encourage more ‘A‘o to breed there. This consisted of two speakers which play calls of the birds at night throughout the breeding season.
“Social attraction projects have been successfully used to attract endangered seabirds in many other countries, most notably New Zealand,” explained Dr. André Raine, Kaua‘i Endangered Seabird Recovery Project Coordinator. “By playing calls of these birds at night, new birds are drawn into the area to see what is going on, and if they find the area suitable may return to breed in following years. This can be a vital conservation tool for this species in other areas in Kaua‘i in the future.”
Many of the Kīlauea Point ‘A‘o pairs this year have been confirmed as currently having chicks, suggesting that the breeding season at Kīlauea Point NWR has so far been very successful. They represent an important, protected population of a species that has seen dramatic population declines of approximately 75% in recent years – with the result that it is now listed as Threatened and protected under the Endangered Species Act.
The precipitous decline of the ‘A‘o is due to a number of reasons. They are attacked and eaten by introduced species such as rats, Barn Owls and feral cats. Other problems include loss of breeding habitat from introduced plants and animals, the effects of light pollution and collisions with power lines.
“It is gratifying to work with a threatened species which responds positively to management techniques,” said Kim Uyehara, Refuge Biologist. “This suggests that the Refuge can play an important role and people can make a difference in conservation and recovery of Hawai‘i’s rare seabirds.”
Although the areas where ‘A‘o breed at the Refuge are closed to the public to protect this listed species, visitors can potentially see or hear them from the shore at dusk when they are coming in to land from the sea. A visit to the Refuge at this time of year will also give visitors the opportunity to see the large nesting colony of ‘U‘au kani along with a range of other native seabirds and the endangered Hawaiian Goose or Nēnē.
Logo courtesy U.S Fish and Wildlife Service