L.A. Zoo Seeks to Take the Sting Out of Traditional Summer Pest

Amid the yellow-footed rock wallaby, the red river hogs and golden-headed tamarin, the Los Angeles Zoo is home to another, less appealing creation of Mother Nature--the wasp.

The stinging creatures descend on the zoo in hordes during the summer, attracted by the ample supply of food--raw meat for the lions, cheeseburgers for the children and many meals in between.

This summer, though, the zookeepers have struck back.

Hanging throughout the zoo are 200 wasp traps designed to catch the annoying insects before they strike. Part-time summer workers have been hired to empty trash cans up to five times a day and steam-clean them regularly. When stings occur, zoo staffers have medication swabs to tend to the injured.

The zoo has not wiped out the pesky wasps--which come in many varieties and can be identified by the number of black lines on their abdomens--but zoo officials say the population has dropped so significantly this summer that it may have become, at least at the zoo, an endangered species.

“We’ve beaten the problem as far as we can tell,” zoo Director Mark Goldstein said. “You can come to the zoo now and you will have trouble finding a wasp.”

Well maybe that’s a bit of an exaggeration. A visitor purchased a cola, sat at an outdoor table near Adventure Island and waited about 10 minutes before one member of the wasp family--a lone yellow jacket--descended onto the rim of the cup. Still, statistics gathered so far this summer show that the problem is greatly reduced.

Last year, there were 84 wasp stings reported at the zoo in the first 20 days of July. Thanks to the wasp crackdown, the number of reported stings has dropped to two.

The zoo had been bracing for another flare-up of wasps this summer. It prepared a special “bee-ware” brochure for visitors, purchased skin cream that repels the pests and stocked up on sting medication. Most of it remains in storage.

It is not unusual for zoos to attract unwanted animal life. Wasps prey on many of the nation’s zoos. San Francisco has had problems with aggressive sea gulls. And pigeons descend on many urban zoos.

Camp counselors who lead swarms of children to the Los Angeles Zoo on summer days deliver lectures about the wasp problem at the entrance and the zoo map handed out to all visitors contains a special wasp warning.

Swarming throughout the zoo’s 77 acres, the wasps have scared away people and stung a significant number of visitors in the past.

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Zoo executives believe the wasps were formerly so omnipresent that they affected ticket revenues.

“It’s been pretty bad in the past,” general curator Les Schobert said. “There’s a lot of them. They nest in the park and attack people who are drinking cold drinks.”

By its very nature, the zoo makes an ideal habitat for wasps.

It is adjacent to lush Griffith Park, an ideal breeding location, and there is an ample supply of food in the animal exhibits and at the outdoor picnic tables. This makes the zoo, which opened in its present location in 1966, a smorgasbord for the hungry wasps, which mix in with the more than 1,500 other animals at the zoo.

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When the wasps are at their worst, Adventures in Food, the zoo’s Mexican eatery, takes on a whole new meaning.

The problem is complicated by the fact that the zoo is limited in how it can combat the pests.

It cannot use insecticides because the chemicals would affect the animals. And it cannot use plastic lids to cover cups of soda because some youngsters launch them into animal exhibits like Frisbees, endangering animals.

This year, the zoo has been experimenting with ways to keep wasps away from sugary soft drinks. It has tried paper lids and domed lids that do not fly as far. But the main emphasis has been on traps designed to catch the reproducing queens.

Zoo volunteer Corki Dada, an entomology graduate student at Cal Poly Pomona, helped design the traps. Consultant Frank Job, a Catalina Island beekeeper and yellow jacket control specialist, has also been hired to tend the traps.

In past summers, the zoo concentrated its traps in food areas. This year, however, the traps went up in March--far earlier than usual--and were hung at critical locations around the perimeter of the zoo to catch the wasps as they entered the property.

Some of the traps are catching as many as 5,000 wasps a week, zoo officials report. That kind of recovery shows that wasps are still in the air and zoo officials acknowledge that the park will never be completely wasp-less.

“Our goal is control--not eradication,” Goldstein said. “Wasps are definitely pests, but they are part of the environment. They are wildlife and we’re a zoo.”