Auckland ducks threatened by bacteria

By WAYNE THOMPSON


Bird rescue volunteers fear hundreds of ducks will die from avian botulism in Auckland parks this summer.

About 100 are already stricken by the toxins of the botulism bacteria, which infects the ducks' food in warm shallow water.

As ponds dry up in Waitakere City, 50 ducks have been found paralysed or dead at the Brandon Rd pond at Westwood Ho, near Kelston.

SPCA inspector Karyn Lowndes said two were saved after intensive care, including feeding of liquids through tubes, cleansing baths and stomach massage.

Nine dead and 15 sick birds were taken from a Glendene pond.

Volunteers and the Waitakere City Council's animal welfare division are sharing treatment of the birds, which takes about five days.

The Auckland Domain has had one of its worst summers for years for botulism among its big duck and eel population.

A dozen birds a week have needed treatment. Without it they would drown when the bug attacks their nervous system and their necks go limp.

North Shore and Manukau City bird rescue volunteers report no toxin-sick ducks among their charges but are worried how birds will be treated if there is a widespread botulism outbreak.

Auckland bird rescue volunteer Pam Howlett said she was disappointed that avian botulism was a problem in Waitakere for the third summer in a row.

She said the council was told that some of its 40 ponds - built to retain stormwater and settle polluting sediments - were too shallow to be healthy habitats for ducks and pukeko.

This was the case with many of the ponds being created throughout Auckland by councils who saw them as cheap solutions to checking stormwater runoff, which erodes streams and pours into them the filth and heavy metals that end up on the beaches.

Waitakere council's water arm, Ecowater, said it had put bales of barley straw in the problem ponds as this was believed to help counter toxins.

Assets and networks manager Richard Taylor said a newly developed product to deal with avian botulism was on its way from the United States and as soon as Auckland Regional Council approval was granted it would be used in the Glendale Pond.

Iwi and regional council consent has been received to deepen the pond. This and other works suggested by an environmental consultant would be done within a month. The Brandon Rd pond would be drained this week to fix a possible underground leak, which had caused lower than normal water levels.

Auckland City parks officer Graham Marchant said botulism prevention measures such as barley straw, weed-eating carp and daily flushing had worked well at Western Springs. But it was difficult to keep water clean and circulating at the Domain pond and resource consent would be sought to remove toxin-infected muck from the pond bottom.

Humans are not affected by avian botulism.