Posted by Janet Harriett on Nov.11, 2009

Photo Credit: Arpingstone

In November, as Americans gear up for Thanksgiving, Wildlife Wednesday will look at several wild birds that are or were hunted as food. This week, we look at the Nene, or Hawaiian goose, driven nearly to extinction when hunters were allowed to pursue the Nene during their nesting season.

The Hawaiian Goose, or Nene (pronounced nay-nay), is the state bird of Hawai’i and one of the rarest species of geese, with a wild population of about 1,800. Before widespread hunting and converting their habitats to agricultural fields, the Nene numbered in tens of thousands on the islands, their only native range. Though limited in number, they’ve adapted to human presence somewhat and are at home on golf courses similar to their native scrub habitat.

An offshoot of the Canada goose, the Hawaiian goose is noted for having a distinct pattern of diagonal stripes on its neck and incomplete webbing on its feet, unlike the fully-webbed feet of the Canada goose that is commonly seen throughout the United States and Canada. Nene are smaller than the Canada goose, though their markings are similar except for the head and neck.

Although females lay 1 to 5 eggs per clutch, the Nene is classified as endangered, with the population sustained only through release of captive-hatched birds from breeding programs meant to preserve genetic diversity among the Nene, since inbreeding becomes a threat when population levels are as low as they were in the 1950s.. On average, only a little more than half of the eggs laid hatch, and 2/3 of the hatchlings succumb to predators or lack of food or water before they fledge. During nesting season, the females incubate the eggs for about a month while the males stand guard. This arrangement made them particularly susceptible to nesting-season hunting before all hunting of the Hawaiian goose was banned in 1907.

Their population is growing on Kaua’i, the only one of the islands where they are safe from the introduced Small Asian Mongoose which feeds on the eggs. Conservation groups that provide protected habitat and supplemental feeding during breeding and nesting season are helping bring up the numbers. Malnourished female birds tend to not lay eggs, so, as with humans, proper prenatal nutrition makes a difference in reproductive success.  Fewer than half of the introduced birds on average take mates in the wild and successfully raise chicks to fledging.

The Nene is also threatened by the toxoplasma gondii in feral cats around the island. The same parasite that can cause problems in human pregnancy can kill the Hawaiian goose.

Where to See Nene

Native wild populations are found only in Hawai’i, on the islands of Hawai’i, Maui Moloka’i and Kaua’i. These flocks live primarily in preserves where their habitat is protected and they are safer from feral predators like cats and dogs. Parks with wild Hawaiian goose populations include Volcanoes National Park, Pu’u Wa’awa’a, Mauna Loa, Kilauea National Wildlife Refuge and Haleakala National Park. With fewer predators on Kaua’i, flocks of Nene are found outside refuges and preserves there.

The Wildfowl and Wetlands Trust reserve in Slimbridge, Gloucestershire, England has a population of Nene. The Hawaiian Goose was introduced to WWT Slimbridge in the 1950s as the birds faced extinction in Hawaii when their wild population hit a low of only 30 birds. The Nene established themselves well on the UK preserve, which operates a captive breeding program to hatch chicks for release in Hawaii. The flock at WWT Slimbridge are reported to be quite tame.

Zoos with Captive Nene

• Houston Zoo, Houston, Texas
• Honolulu Zoo, Honolulu, Hawaii
• Alameda Park Zoo, Alamagordo, New Mexico
• Pana’ewa Rain Forest Zoo, Hilo, Hawai’i

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Posted under Living, Nature and Environment.