Birds’ Flight From Area Points to Malathion

About this time every year, avid bird-watcher Bill Supri counts 30 to 50 quails a day that come skittering down a hill in his Camarillo Springs back yard, often with a covey of up to 16 babies scrambling behind them.

“They’re about the size of little golf balls, only they have fur on them,” Supri said.

But this year, he has seen few quails or blackbirds--also abundant in previous years. He suspects that malathion sprayed to combat the Medfly infestation in eastern Camarillo is to blame.

“There are practically none this year,” he said. “The choppers with malathion have been over my house numerous times. It’s scary.”

Ornithologist Elliott McClure has also noticed a marked decrease in the number of house finches, the most common local bird. He catches and bands birds as a volunteer for the U. S. Fish and Wildlife Service.

“Over 17 years, I caught an average of 160 house finches in the month of May,” he said. “In May of this year, I caught one.”

A type of flycatcher, which can usually be found in the area this time of year, has also been absent, he said.

Although McClure said he does not have enough information for a scientific conclusion, he suspects that either disruption from helicopters flying overhead may have spooked the birds or the malathion may have temporarily knocked out insects on which some species of birds feed.

“It’s very possible that was the cause for the reduction in population,” he said. But he cautioned that at this point he only has observations.

McClure, who also teaches classes in bird-watching at Ventura College, added that some species of birds appear not to have been affected at all. And some others that have been absent are beginning to reappear, although there seem to be far fewer young or juvenile birds than normal, he said.

Malathion was sprayed in 14 aerial applications between October, 1994, and May of this year. The infestation, which was discovered on the grounds of St. John’s Seminary in eastern Camarillo last fall, caused an estimated $50 million in damage to agricultural crops.

The pesticide, which was mixed with corn syrup to attract Medflies, was applied in amounts officials believed too small to harm humans. But, because malathion works by attacking the central nervous system, it was also expected to kill large numbers of insects other than Medflies, officials said.

“When you come in with malathion, you expect that you’re going to knock out a lot of non-target insects,” said Les Ehler, a professor of entomology at UC Davis who has done research on the effects of malathion. “What could be happening is there could be a reduction in the birds’ food supply.”

House finches feed partially on insects and partially on grains and seeds. Quails and blackbirds are mostly seed eaters, and the flycatchers feed on insects.

Veda Federighi, a spokeswoman for the California Department of Food and Agriculture, said a temporary decline in bird populations following repeated malathion applications is normal.

“It has been seen that birds move away after malathion is applied, but then they come back,” she said. “Because when the insects come back, so do the birds.”

And McClure said that may have already started to happen.

“I think the spray upset the ecosystem and they left. But now, with no more disturbances to the ecosystem and no more helicopters, they are starting to come back.”

Although his banding virtually stopped in May and June as the birds stayed away, McClure said their numbers are gradually increasing.

“On Thursday, I got 10 house finches,” he said. “It should have been 50. But of the 10, there was only one juvenile. And there are usually many more juveniles.”

But he noticed no changes in the populations of other species, he said.

Orioles, which are insect eaters, were completely unaffected, he said, because of their migratory patterns. During the sprayings, they were wintering in South America.

Neither has he seen a decrease in the number of hummingbirds, which are known to have an affinity for sweets.

“I would have expected them to be affected, with all that sweet syrup sitting on flowers, but they weren’t,” he said. “We’re still talking about an unknown here.”

And even though McClure’s house is only a few miles from Supri’s, McClure said he has not seen a decline in quails in his area, more proof that he needs more information before coming to scientific conclusions, he said.

“I always fault my students on their science projects for not having enough tests,” he said.

Supri, president of the Conejo Audubon Society, began bird-watching eight years ago, gradually adding landscaping to his back yard to attract birds, butterflies and wildlife. Each year, until the past year, he has seen their numbers increase.

“On a quiet day, you could hear hundreds of bees buzzing around out back,” he said. “This year, I’ve seen three or four.”

He looks forward to the time when his yard is again humming with life.

“I’m real glad to see some of them coming back,” he said.