Kaua'i's population of nene, or Hawaiian geese, is between 600 and 650 birds and growing — one of the great Hawaiian endangered species success stories.

Wildlife officials today will release another 29 young birds near the old Koke'e NASA station, said Alan Silva, wildlife management assistant with the state Division of Forestry and Wildlife.

While fossil evidence shows there were native geese on Kaua'i before human presence, they have been absent in recent centuries — until a quarter-century ago.

The powerful winds of Hurricane Iwa broke open the cages of captive birds at Kipu Kai Ranch in 1982. Those birds got loose and thrived in the wild, showing that the mongoose-free island was good potential goose habitat. State wildlife folks backed up the populations with a series of releases of birds bred on Maui.

Today, it's not uncommon to see flocks of honking birds flying overhead in the Lihu'e, Koloa, Koke'e and Kilauea areas.

One problem spot for the geese, as well as for humans, is the Kaua'i Lagoons golf course and waterway property at Nawiliwili. There are 50 to 60 nesting pairs of a total of 180 to 190 nene that frequent the lagoons.

The golf course and lagoon project is right next to Lihu'e Airport, and geese readily fly over the fence into the runway area. Silva said the state hopes to stabilize or reduce the population at the lagoons to minimize the chance of aircraft strikes. The 29 birds being released at Koke'e are fledglings hatched at Kaua'i Lagoons.

"We've been doing this for about two years," he said.

Koke'e may be a safer habitat for the animals than the resort golf facility. Of about 100 nene hatched at Kaua'i Lagoons this season, only about 50 survived long enough to be rescued and moved.

Among the causes of fatalities are being hit by golf balls and run over by vehicles, but also by predation by other animals. An unusual source of predation: When the tiniest new goslings go for a swim, they are sometimes eaten by the big tucunare or peacock bass in the lagoons.

"I've seen it happen," Silva said.

Transferring animals capable of flying is always challenging. When state wildlife folks tried to establish a population in remote Nu'alolo 'Aina valley on the Na Pali coast, most of them quickly flew to the ridges at the top of the valleys. And some began hanging out in parking lots, where visitors gave them handouts and the birds were endangered by cars.

If you have a question or concern about the Hawaiian environment, drop a note to Jan TenBruggencate at P.O. Box 524, Lihu'e, HI 96766 or jant@honoluluadvertiser.com. Or call him at (808) 245-3074.