Largest Cat-Proof Fence Built in the U.S. to Protect Hawaiian Birds from Feral Cats

Work is complete on what could be the largest cat-proof fence in the United States, designed to protect the federally endangered ‘ua‘u, or Hawaiian petrel, from the birds’ primary threat: feral cats.

Park staff install the cat-proof fence in rough and rugged high-elevation lava fields on the slopes of Mauna Loa. The five-mile-long fence protects more than 600 acres of Hawaiian petrel habitat, and could be the longest of its kind in the United States. NPS Photo.

Park staff install the cat-proof fence in rough and rugged high-elevation lava fields on the slopes of Mauna Loa. The five-mile-long fence protects more than 600 acres of Hawaiian petrel habitat, and could be the longest of its kind in the United States. NPS Photo.

The seafaring ‘ua‘u nests in deep lava rock burrows on the rugged high-altitude slopes of Mauna Loa, and, despite the remote location, are not safe from cats. In order to protect the species, the National Park Service (NPS) teamed up with the National Fish and Wildlife Foundation, U.S. Fish and Wildlife Service, American Bird Conservatory, Hawai‘i Pacific Parks Association, and the Pacific Cooperative Studies Unit at the University of Hawai‘i (PCSU), to build the five-mile long cat barrier fence in Hawai‘i Volcanoes National Park. The specifically designed barrier is more than six feet high, and has a curved top section that prevents cats from climbing over it.

Construction began in 2013, and was limited to January through May to avoid disturbing nesting birds. The seabirds spend most of their lives at sea, and come to land only during breeding season. ‘Ua‘u return to Hawai‘i Volcanoes National Park briefly in April to prepare nest sites, and return in early June to lay a single egg. The fluffy chicks hatch in August and remain in their burrows until November when they fledge or take their first flight out to sea. Adults, eggs and chicks are extremely vulnerable to predators throughout the long breeding season as all activity occurs on the ground.

Cat-proof fence aerial/Courtesy of Scott Hall/NFWF

Cat-proof fence aerial/Courtesy of Scott Hall/NFWF

The high-altitude project was grueling. NPS and PCSU fence crews worked and camped at elevations between 8,000 and 10,000 feet, in steep and loose lava rock terrain, and in weather that ranged from hail, and high wind, to extreme heat. The site is very remote and all materials, gear and staff had to be flown in and out. But the discomfort paid off: the fence now protects more than 600 acres of ‘ua‘u nesting habitat on Mauna Loa.

“To our knowledge, this is the largest fence of its kind in the U.S. To build such a fence is an incredible feat, and an important victory for a native species that is extremely rare on Hawai‘i Island,” said NPS biologist Kathleen Misajon. “Through the partnership of the cooperating organizations, the cat-proof fence will protect these amazing seabirds and support the expansion of this small population,” she said.

The endangered Hawaiian petrels are more typically seen on neighbor islands. The species is very rare on Hawai‘i Island, with just 75 nesting pairs in Hawai‘i Volcanoes National Park, and another small population on the slopes of Kohala. The park and cooperating partner agencies have studied this remnant population of ‘ua‘u on Mauna Loa since the early 1990s, both on the ground and more recently, through remote game cameras. The birds only come and go at night, nest in deep cracks and crevices in the lava, and are rarely seen.

Both parents take turns incubating a single egg and later, feeding the chick. They fly from high atop Mauna Loa to forage in the Pacific Ocean, ranging as far north as Washington State before returning to the nest to feed their chick.

For more information on ‘ua‘u on Mauna Loa, watch this six-minute video on the park website:

Growing Native Plants for Species Recovery and to Protect Land and Watersheds

When Silene perlmanii, an extremely rare small shrub with delicate white flowers, was discovered on O‘ahu by botanist Steve Perlman in 1987, just 20 individuals remained in the wild. Within three years, only 6 plants remained, dwindling to a single individual by 1994. The decline of this species at the last known wild site has been attributed to aggressive weeds and introduced ungulates damaging the habitat.

native plants

According to Hawai‘i state botanist Maggie Sporck-Koehler, “This situation is not uncommon in Hawai‘i, which has the unfortunate distinction of having an extremely rare flora, and is often referred to as the ‘endangered species capital of the world.’” Hawai‘i’s flora is exceptionally unique with approximately 90% of flowering plants and 70% ferns found nowhere else on earth.

All that is preventing the loss of these unique species forever is a small group of dedicated conservationists, including the Department of Land and Natural Resources (DLNR), Division of Forestry and Wildlife (DOFAW), which conducts several types of plant conservation activities with the help of partners statewide, including the U.S. Fish and Wildlife Service, Hawai‘i Rare Plant Restoration Group, and Research Corporation of the University of Hawai‘i.

One significant component to DOFAW’s ongoing plant conservation and habitat protection projects are the state-run plant nurseries. The rarest plant species are grown in the state’s mid-elevation rare plant facilities located on Hawai‘i island, Maui, O‘ahu, and Kaua‘i.

DOFAW district botanists and experts from one of DOFAW’s most highly specialized conservation partners, the Plant Extinction Prevention Program (PEPP), carefully and strategically collect from rare plants in the wild, in places where natural plant regeneration is not occurring due to a variety of threats. Some of the seeds and other propagules collected by these expert botanists are taken to those nursery facilities to be grown and eventually outplanted back into protected areas in the wild.

The ultimate goal of DOFAW’s district botanists and the PEPP coordinators is to keep rare and imperiled species from declining further and to help restore these species and ensure their survival long into the future. In the case of PEPP, preventing extinctions is their highest priority, with a focus on species with fewer than 50 individuals remaining in the wild. The mid-elevation rare plant facilities propagate primarily state and federally listed threatened and endangered (T&E) species.

In the case of Silene perlmanii and many other species, seed collections were made just in time. According to O‘ahu PEPP coordinator Susan Ching Harbin, outplantings of these nursery-grown specimens have been occurring since 2002 thanks to initial work done by the National Tropical Botanical Garden. In recent years, PEPP has planted over 100 individuals of this species in two locations in the southern Wai‘anae mountains, with another 100 to be planted out this coming fall. Says Ching Harbin, “Outplants are looking great. One of the outplanting sites has some natural regeneration (although the numbers are very small).”

While preventing extinctions is one of the important jobs performed by DOFAW and its partners, supporting restoration of ecosystem structure and function is another task of state nurseries. They also propagate many different species of native plants, some T&E, some common species, and numerous trees for windbreak purposes. The State Tree Nursery provides high quality native tree species and windbreak trees and plants for both the public and DLNR-state sponsored out-plantings and reforestation projects.

DOFAW and partners use state-propagated native plants to help restore natural areas on a large scale in the Nakula Natural Area Reserve and Kahikinui Forest Reserve on Maui. The leeward south slopes of Haleakala were once covered in koa-‘ohi‘a montane forests and alpine shrublands but many years of impacts from feral ungulates and invasive plant species had resulted in the ecosystem being reduced to eroded grasslands with scattered trees. Without trees to capture the moisture, streams which used to flow have dried up. Within Nakula, DOFAW staff and partners have restored over 97 acres of the degraded land with over 64,000 Hawaiian native plants, subsequent to fencing and removal of feral cattle, goats, deer, and pigs. In neighboring Kahikinui, another 50,000 native plants have been planted, with high levels of survivorship.

Several important native Hawaiian tree species (some examples of these are koa, mamane, wiliwili, ‘iliahi, naio, and kolea lau nui) as well as several native species of shrubs, vines, and herbaceous understory plants (e.g. ‘ilima, maiapilo, ‘u‘ulei, pilo, ‘a‘ali‘i) have been successfully propagated and outplanted into highest priority restoration sites. By reforesting degraded areas which have lost their native Hawaiian biodiversity of plants, this work will allow for their recovery, and also the recovery of the birds, snails, and other invertebrates that are native residents of these areas.

DLNR & YOU-Growing Native Plants to Protect Forests & Watersheds from Hawaii DLNR on Vimeo.

As a member agency, DOFAW supports the Hawai’i Rare Plant Restoration Group’s recently released Hawai‘i Rare Plant Code of Conduct to help guide forest visitors. A link to it is listed below under resources.

Talk Story Sessions Set for Rodent and Mongoose Control and Eradication Methods to Protect Native Habitats

The U.S. Fish and Wildlife Service (Service) and Hawaii Department of Land and Natural Resources, Division of Forestry and Wildlife (DOFAW) will hold a series of talk story sessions about methods to control and eradicate invasive rodents and mongooses to protect native species in Hawaii.  The agencies are co-leads in developing a draft programmatic environmental impact statement, which will analyze the impacts of and alternatives to controlling these invasive animals for the protection of native wildlife, plants, and habitats that support them.

Mongoose trap

“Introduced rodents and mongooses in Hawaii pose a significant threat to many of Hawaii’s native plants and animals,” said Suzanne Case, Chairperson of the Hawaii Department of Land and Natural Resources. “It is important that we have a discussion with a wide variety of interested people so we can comprehensively address the damage these rodents and mongoose have on Hawaii’s ecology, culture, and way of life.”

“We really want to hear what communities would like us to consider in this analysis, including what methods should be considered and what are some alternatives,” said Mary Abrams, Field Supervisor for the U.S. Fish and Wildlife Service. “Methods to control rodents and mongooses in urban and agricultural areas currently exist, but those tools and methods aren’t always effective or available for use in conservation areas.  This process will look at rodent and mongoose control efforts worldwide, and document the most appropriate ones that could be used in Hawaii.”

The talk story sessions will be held on the following dates and islands:

Oahu from 6:30 to 8 p.m.:

  • February 25 (Thursday) at the McKinley High School cafeteria located at 1039 S King St, Honolulu, HI 96814
  • March 17 (Thursday) at Hale Ponoi located at 91-5420 Kapolei Parkway, Kapolei, HI 96707

Molokai from 5:30 to7:30 p.m.:

  • March 1 (Tuesday) at the Mitchell Pauole Center located at Ainoa Street, Kaunakakai, HI 96748

Lanai from 5:30 to 7:30 p.m.:

  • March 3 (Thursday) at Lanai Public Library located at 55 Fraser Ave, Lanai City, HI 96763

Kauai from 6 to 8 p.m.:

  • March 7 (Monday) at the Waimea Neighborhood Center at 4556 Makeke Road, Waimea, HI 96796
  • March 8 (Tuesday) at Chiefess Kamakahelei Middle School Cafeteria at 4431 Nuhou Street, Lihue, HI 96766

Maui from 6 to 8 p.m.:

  • March 10 (Thursday) at Lahaina Civic Center at 1840 Honoapiilani Hwy, Lahaina, HI 96761
  • March 11 (Friday) at Kahului Community Center at 275 Uhu Street, Kahului, HI 96732

Hawaii from 6 to 8 p.m.:

  • March 14 (Monday) at University of Hawaii-Hilo, College of Tropical Agriculture and Human Resources, Komohana Research and Extension Center (conference rooms A and B) located at 875 Komohana Street, Hilo, HI 96720
  • March 15 (Tuesday) at West Hawaii Community Center located at 74-5044 Ane Keohokalole Highway, Kailua-Kona, HI 96740. U.S. Fish & Wildlife Service

In addition to these talk story sessions, the public is invited to submit written comments through April 7, 2016.  Comments may be made to either agency for joint consideration in the following ways:

Electronically: Follow the instructions for submitting comments on Docket No. FWS–R1–ES–2015–0026.

  • U.S. Mail: Public Comments Processing, Attn: FWS–R1–ES–2015–0026; Division of Policy and Directives Management;
  • U.S. Fish and Wildlife Service; MS: BPHC; 5275 Leesburg Pike; Falls Church, VA 22041–3803.
  • Website click on “Get Involved” and enter a comment.

Once the comment period closes, both agencies will review the comments received and begin development of the document. For the Service, comments previously submitted during the first comment period do not need to be resubmitted. The draft programmatic environmental impact statement will be published in both the Federal Register and the Environmental Notice and provide another public comment period for review. For more information:   or

Commentary – Bureau of Interior Wants To Control New Development in North Kona

I’m deeply concerned about the actions of the National Park Service and U. S. Fish and Wildlife Service. These federal agencies intend to control how much new development happens in North Kona it seems.

For example, the National Park Service wants the State of Hawaii to designate the Keauhou aquifer as a water resource management area and the U.S. Fish and Wildlife Service wants to assign nearly 19,000 acres of land in North Kona as a critical habitat area.  In addition, the
National Park Service was the first entity to intervene in the stalled Queen Kaahumanu Highway phase 2 widening project’s section 106 process in early 2011.

These requests, if approved, will impact all new developments in North Kona. It strips home rule authority from the County of Hawaii and adds an additional layer of bureaucracy to the entitlement process.

I firmly believe the County and State of Hawaii are in a better position to manage our resources than a bunch of bureaucrats in Washington D.C.

Aaron Stene