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The Honolulu Advertiser
Posted on: Thursday, October 16, 2003

Conservation group working to restore islets' environment

Graphics (open in new windows):
 •  Bird sanctuaries off O'ahu
 •  Bird sanctuaries off Neighbor Islands

By Timothy Hurley
Advertiser Staff Writer

If, as Mark Twain said, Hawai'i is the loveliest fleet of islands that lies anchored in any ocean, then the state's offshore islets are the junior members of the group, floating alongside their larger neighbors in picturesque formation.

Manana, the landmark also known as Rabbit Island, lies off Makapu'u on the eastern end of O'ahu. The islet's wildlife is recovering from years of damage by an introduced colony of rabbits that have since been eradicated.

Bruce Asato • The Honolulu Advertiser

But don't dismiss the hundreds of islets, rocks and sea stacks as mere extensions of the main islands. Scientists say their relative isolation has made them the last refuge for sea birds once found in vast numbers on the main islands, and home to rare plants and insects.

Yet their isolation stretches only as far as the nearshore waters, a proximity that makes them vulnerable to rats, ants, weeds and other things that plague the main islands.

Enter the Offshore Islet Restoration Committee, formed a year and a half ago to improve the environment of the smallest of Hawai'i's islands. The group is working to survey dozens of offshore islets in hopes of coming up with a plan to conduct environmental restoration.

The organization includes members representing the U.S. Fish and Wildlife Service, the state Division of Forestry and Wildlife, the Nature Conservancy, Bishop Museum, the University of Hawai'i and the National Park Service.

Committee chairman Chris Swenson, Pacific Islands Coastal Program coordinator with the Fish and Wildlife Service, said he had no problem recruiting members for the project.

"Everybody loves the offshore islets," he said. "These are mini-microcosms of what Hawai'i once looked like. And everyone seems to love the seabirds."

The islets range in size from a couple hundred acres to only several dozen square feet. Most of them are on the windward sides of the islands. Islets are remnants of larger volcanoes or were formed by eruptions in their own right.

36 in bird refuge

Kailua's flat islet, Popoi'a, is home to wedge-tailed shearwaters.

Bruce Asato • The Honolulu Advertiser

Many support some kind of biological community. It is estimated that 50 or 60 islets have sea bird colonies, while 36 are part of the Hawai'i State Seabird Sanctuary, a refuge established by the state in 1981.

The archaeology of the major offshore islets indicates use by ancient Hawaiians, and some are mentioned in song, chant and legend. More recent history points to failed agricultural ventures, including the raising of animals.

Most are now uninhabited and devoid of development, with the notable exception of Coconut Island, or Moku o Lo'e, which is home to the University of Hawai'i Institute for Marine Biology.

Some of the islets sport lighthouses, such as Molokini, a popular snorkeling destination that lies between Maui and Kaho'olawe. Ka'ula Rock, southwest of Ni'ihau, is a military target range, but only inert warheads have been used in recent years. And the Windward O'ahu islets are popular with kayakers, but some are off-limits.

In the past decade, conservation managers and scientists have turned a closer eye on the islets, recognizing them as special places with outstanding potential for environmental restoration and research.

Dave Smith grew up in Lanikai with a fondness for the islets that dot the Windward shore. When he became O'ahu manager for the state Division of Forestry and Wildlife in the early 1990s, he began to realize how much ecological damage was occurring out there. Previous managers essentially followed a hands-off policy, a sort of protection without active management.

Smith decided the islets deserved better, so he stepped up public education, law enforcement and monitoring. Today, there are aerial photos of the islets, a geographic information system database and more than six years of island surveys.

"They are such neat geological features. People just can't help going out there," he said.

Swenson said there's tremendous opportunity for restoration. Because of their small size, the islets can easily be purged of noxious invaders. "And when an alien is gone, you don't have to worry about the island being trashed in the near future," he said.

Mokoli'i rid of rats

One recent success story happened on Mokoli'i, the distinctive islet that lies off Kualoa in Windward O'ahu and is commonly known as Chinaman's Hat.

Under the direction of Smith, a community group used poison and traps to eradicate the islet's rats.

The results were almost immediate: 126 wedge-tailed shearwater chicks fledged in 2002, compared to just one chick in the previous three years combined.

While the sea birds — shearwaters, terns, noddies and rare boobies and albatrosses — stand to be the greatest beneficiaries of the restoration efforts, Hawai'i's rare plants also will reap rewards.

Just before he retired at the end of 2002, former Maui District Forestry and Wildlife manager Bob Hobdy led a mission to plant endangered dwarf naupaka on several Maui and Lana'i islets.

"Dwarf naupaka used to be fairly widespread in the 1800s, but primarily grazing animals wiped it out," Hobdy said. "Now, it's clinging to life in only some remote areas. We thought the offshore islets were the best bet to help save the species."

With a $4,000 Fish and Wildlife Service grant, Hobdy and a crew of volunteers with the Maui Nui Botanical Gardens and other conservation groups collected cuttings on Maui and accomplished the plantings with the help of helicopters, boats and even surfboards.

So far, the Offshore Islet Restoration Committee has spent about $120,000 on various projects. Swenson said the committee is hoping to land about $600,000 for a five-year plan that includes surveys of islets, restoration and replanting, plus a public education program.

He said the group is hoping to hire a sea bird education coordinator, create a Web site and maintain a GIS database.

The islets won't be the only land masses to benefit from the research. Swenson said there are lessons to be learned for restoration on the main islands.

For example, biologists are hoping to conduct a test project in which rat poison will be spread from the air on Lehua, a crescent-shaped islet west of Ni'ihau and popular with sea birds.

"It's an excellent opportunity to try this out in an uninhabited area," Swenson said

The aerial application of rat poison is common in New Zealand but hasn't been approved for widespread use in Hawai'i, and conservation managers here are hopeful the method eventually will be allowed to help accelerate habitat protection across the state.

Ants are another problem on the islets. Sheldon Plentovich is working on her doctorate looking at how the ants attack ecosystems, using the Mokulua islets off Lanikai as her laboratory. In her study, she eradicated ants on two islets and left the ants on two others, while examining the ongoing health of each island's sea birds.

Ants eating chicks

While her study is still a couple of years from completion, it appears that the ants are indeed having a negative effect on the sea birds. She has discovered wedge-tail shearwater chicks literally being eaten to death by ants.

Plentovich's interest in the offshore islands doesn't end with her research.

For the past two years, she has been working with fourth- and fifth-graders at Lanikai Elementary School on a science project studying the Mokulua islets. The students recently designed some signs that will be posted on the islets to remind visitors to respect the native species and to leave pets at home.

"The more information we can give to the public about how fragile and special these islands are, the better," she said.

The committee's restoration project should provide data on some islets that have not been surveyed for many years, or in some cases, not at all. The discovery of a new species isn't out of the question.

Kaua'i conservation biologist Ken Wood knows what that's like. During a biological survey of Kaho'olawe in 1992, he and then-National Tropical Botanical Garden colleague Steve Perlman found Kanaloa kahoolawensis on a rocky stack on the southern coast of the island. It was the first new plant genus to be discovered in Hawai'i since 1913.

Wood said the historic find made him realize just how important the offshore islets are as refuges for endangered plants and seabirds that can no longer make it on the main islands.

It was then he decided to devote much of his work to conservation of the islets.

Since then, he has concentrated on some of the lesser known islets off Kaho'olawe and Moloka'i, including the islet of Huelo, home of the last lowland forest of the Pritchardia, or loulu, fan palms in the main islands.

"We don't have the islets pristine yet. We have the beginnings," Wood said. "Each one is a challenge, each one has problems."

Reach Timothy Hurley at thurley@honoluluadvertiser.com or (808) 244-4880.

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Source: Offshore Islet Restoration Committee