Posted on: Wednesday, July 25, 2001

Botulism kills 30 birds in Maui sanctuary

By Timothy Hurley
Advertiser Maui County Bureau

KAHULUI, Maui — Thirty wetland birds, many of them endangered species, have died of avian botulism at Kanaha Pond State Wildlife Sanctuary, wildlife officials reported yesterday.

The outbreak of the disease, which does not affect humans, was confirmed July 11 following the discovery of a dead Hawaiian coot.

State wildlife officials have been searching the sanctuary regularly to remove dead birds since the confirmation and there's been no letup in the discovery of casualties, said Fern Duvall, sanctuary manager.

Meanwhile, officials at Kealia Pond National Wildlife Refuge, seven miles away on Maui's south coast, report an increase in dead-birds. However, there are no confirmed cases of avian botulism, according to Kealia refuge manager Glynnis Nakai.

Five Hawaiian coots were sent from Kealia to Honolulu for a necropsy in April, but the lab results turned up negative, Nakai said.

"We're treating this like it is botulism, but we can't say we have (the disease) yet," Nakai said. She added that her staff has stepped up the search for dead birds, conducting twice-weekly searches across the 700-acre refuge.

While the bacterium that causes the disease is found in Hawai'i's soil naturally, the botulism toxin is produced only under certain conditions.

Those conditions typically are stagnant water, warm temperatures and decaying vegetation. The birds are infected when they eat toxin-laden invertebrates.

At Kanaha, the disease has killed 12 Hawaiian coots, 10 Hawaiian stilts, five koloa or Hawaiian ducks and three black crown night herons. The coots, stilts and koloa are endangered species.

Duvall said one weakened bird, a koloa, was rehabilitated and released back into the pond Friday.

The last outbreak of avian botulism at Kanaha was in 1997, while officials at Kealia dealt with it last year.