When I first landed on what was Rat Island in 2007, it was an eerily silent place. A typical Aleutian island is teeming with wildlife, swirling with noisy, pungent birds. Not this place. It was crisscrossed with rat trails, littered with rat scat, scavenged bird bones, it even smelled…wrong,” reports Stacey Buckelew, an Island Conservation biologist. Buckelew first visited the island to help document centuries of damage to native birds and plant species from introduced invasive Norway rats (Rattus norvegicus).
Flash forward to today-five years after the successful removal of invasive Norway rats by the U.S. Fish and Wildlife Service (http://www.fws.gov/alaska/nwr/akmar/) (The Service),The Nature Conservancy (http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/alaska/index.htm) (The Conservancy) and Island Conservation (http://www.islandconservation.org/) (IC). Much has changed.
“The island is hardly recognizable among the cacophony of birds calling everywhere; it’s alive with bird fledglings-teals, eiders, wrens, sparrows, eagles, peregrine falcons, gulls, sandpipers. The island is transforming,”says Buckelew, who has just returned from the now renamed Hawadax Island where she is helping document early stages of an extraordinary recovery.
For the first time ever, breeding tufted puffins (Fratercula cirrhata) have been documented on the island in the Alaska Maritime National Wildlife Refuge. Species thought to have been extirpated because of the rats, such as Leach’s storm-petrels (Oceanodroma leucorhoa) and fork-tailed storm-petrels (Oceanodroma furcate), have been recorded on-island.
Ground-nesting and shorebird numbers are increasing as well. A 2008 survey documented 9 glaucous-winged gull (Larus glaucescens) nests. This summer, an identical survey discovered 28 nests, a three-fold increase. Black oystercatchers (Haematopus bachmani) and rock sandpiper (Calidris ptilocnemis) nests have also increased significantly.
Song sparrows (Melospiza melodia) thought to be near extirpated by rats and snow buntings (Plectrophenax nivalis) also decimated by rats are rebounding as well as. “During monitoring surveys in 2007 and 2008, we didn’t record a single song sparrow. This summer, hardly 3 minutes would pass without hearing a sparrow,” said Buckelew.
“The return of bird life to Hawadax Island is an inspiring example of what we can accomplish when we work together to fix a longstanding problem. It’s a win for people, and it’s a win for nature,” said Randy Hagenstein, Alaska state director for The Nature Conservancy.
Norway rats were spilled onto the island’s rocky shores in a 1780’s shipwreck. Since then the rats had decimated native bird species by eating eggs, chicks, and adult birds and by ravaging habitat. In early October, 2008, after many years of intensive planning the project partners successfully removed the rats using rodenticide bait.
For several years leading up to implementation, project partners collected pre-removal baseline data on the island’s bird, plant and intertidal species. Since the removal of rats, partners have been back several times to monitor these same species. These early increases in native bird populations are expected to lead to more ecosystem recovery. Seabirds drive the vegetation communities on rat-free islands by delivering marine based nutrients to the soil. As seabirds increase on Hawadax, scientists expect plant communities to return to this natural state.
“What a joy it was to visit Hawadax Island this summer,” said Alaska Maritime National Wildlife Manager Steve Delehanty. “There were birds everywhere. There is no more valuable action we can take on a National Wildlife Refuge than making it once again a haven for wildlife.”
The project has also helped to restore an important Native presence. In 2012, the Aleutian Pribilof Islands Association, representing the Unangan (Aleut) community championed and officially restored the island’s original Unangan name. Hawadax translates to “those two over there” (an accurate description of the two knolls dominating the island’s topography). While the island is currently uninhabited, it was used by the Unangan people for millennia.
Other species inadvertently impacted by the operation are rebounding today. There were unfortunate losses of bald eagles (Haliaeetus leucocephalus) that predated on rats that had consumed the bait. Fortunately, more nests and chicks were observed with each monitoring trip, and in 2013 the island is once again home to five active eagle nests, including four with chicks.
Globally, 40% of all species threatened with extinction today1 depend on islands, yet islands comprise a mere 5% of our world’s land area. Since 1500, 80% of all recorded extinctions worldwide have occurred on islands. Damaging introduced invasive species such as rats are implicated in nearly half of these. To date, there have been over 1100 successful removals of invasive species including 500 rat removals worldwide. Once invasive species are removed from islands, native species and the island’s natural balance often recovers with little or no further intervention.
“Hawadax Island is on a trajectory for recovery and the ecological gains we are witnessing are tremendous. They are a sustained testament to a conservation methodology and partnership that works,” said Gregg Howald, North America Region Director for Island Conservation. “We have had similar successes working with The Service and The Conservancy elsewhere. We are committed to a long-term conservation partnership to apply these transformative conservation tools.”
Hawadax Island is part of the Alaska Maritime National Wildlife Refuge and the National Wilderness Preservation System. The island is located about 1300 miles west of Anchorage in Alaska’s Aleutian Islands. The 6,861 acre island is uninhabited by humans. Steep coastal cliffs, a small central mountain range (with a maximum elevation of about 950 feet), and broad, rolling plateaus of maritime tundra define this treeless island. There are no native land mammals on Hawadax but there are marine mammals on off-shore rocks and islets.
Contact:
– Heath Packard, Island Conservation, 360-584-3051
– Dustin Solberg, The Nature Conservancy in Alaska, 907-424-5101
– Steve Delehanty; Poppy Benson U.S. Fish and Wildlife Service, 907-235-6546