Admiralty Island

Old growth forest on Admiralty Island
© Russell Hood

Biological Significance:

Known to the Tlingit people as Kootznoowoo or “Fortress of the Bears,” Admiralty Island, located in Southeast Alaska, supports one of the highest concentrations of brown bears in the world. Estimated at a density of one bear per square mile, Admiralty Island provides habitat for about 1700 bears — more bears than in the lower 48 states combined. The brown bears of Admiralty, a genetically distinct population, can stand more than nine feet tall and can weigh over a thousand pounds — ranking them among the largest land mammals in North America. The bears find abundant food in the island’s salmon-rich streams and populations of Sitka black-tailed deer. The key to Admiralty’s bountiful wildlife is its old growth temperate rainforests: Admiralty harbors among the largest intact stands remaining in the world. Generations of trees of varying ages comprise a complex mosaic of vegetation. Natural openings in this mosaic allow just enough light to grow plants on which Sitka black-tailed deer thrive. The forest also provides the large trees bald eagles require for perching and nesting. It has been estimated that nearly 2500 bald eagles reside on Admiralty Island. Admiralty’s significant tidal flats, muskeg and other wetlands also provide nesting and staging habitat for waterfowl and shorebirds.

Threats:

Although most of Admiralty island is a designated National Monument, there are biologically important, privately-owned inholdings scattered around the island. The threats to the biological riches of Admiralty will likely originate from incompatible uses of these inholdings and associated tideland leases. Moreover, Admiralty Island is one of the United State’s most spectacular national monuments. The Island and its population center, Angoon, with its striking setting at the mouth of Mitchell Bay, are alluring destinations for adventurous travelers. Angoon and the island will certainly face a variety of issues caused by more intensive visitor pressure, including the need to build infrastructure, engage in land-use planning, and make decisions that will have long-term impacts on the health of sensitive natural habitats in the area.

Conservancy Action:

The Nature Conservancy in Alaska considers Admiralty Island one of the best examples of unfragmented coastal temperate rainforest remaining in the world. The Conservancy acquired 104 acres of coastal, old-growth rainforest and salt marsh on Favorite Bay and transferred it to the Forest Service for management as part of Admiralty Island National Monument. The acreage is located at the head of an important arm of the larger Mitchell Bay, one of the most biologically important estuaries in Southeast Alaska. The property was under immediate threat of development for a lodge or subdivision. As much of the island is protected through the monument, the Conservancy will focus its land acquisition on private inholdings like the Favorite Bay parcel in order to prevent fragmentation or degradation of important wilderness areas.