Days of the Locust

They forced the evacuation of a jury assembly room at an Indio courthouse. Children scrambled to catch them among the seats at a weekend game at Edison Field in Anaheim.

They descended so thickly overnight on the streets of Lake Havasu City in Arizona that motorists couldn’t even see the center yellow lines.

Just this week, staff members at the Natural History Museum of Los Angeles County scooped them from their parking lot to display in their insect zoo.

Grasshoppers normally found in deserts and grassland are being spotted in unusual numbers on driveways and sidewalks from the Inland Empire to the shores of Long Beach.

These nimble, winged creatures seem partial not to grassy knolls but to parking lots and lights, according to eyewitnesses who describe them moving moth-like toward street lights and even a Wal-Mart.

No one seems sure why this emissary from nature is braving one of the most paved-over corners of the continent this spring.

But the stories are legion. And though they are being found in the Los Angeles Basin in unusually high numbers, still more are being found in rural desert areas. And in cities such as Blythe and Laughlin, Nev., residents awoke Monday to find huge congregations of hoppers.

“Millions. Just millions,” said entomologist Larry Shaw after walking across sand dunes near Brawley last week. “They just fly up before you by the hundreds.”

Experts in Southern California and elsewhere are astonished and fascinated by the phenomenon.

“They just came out of nowhere,” said Rodney Lampman, an entomologist for San Bernardino County who began getting calls from curious and worried residents two weeks ago.

“It’s quite clear that there’s a huge population explosion going on,” said grasshopper expert Daniel Otte, curator of insects at the Academy of Natural Sciences in Philadelphia.

The boom is undoubtedly linked in part to the El Nino rains, but experts don’t entirely understand why this particular grasshopper is appearing in so many places at once.

They hasten to assure those alarmed by the onslaught that these hoppers don’t bite or sting. Nor do they pinpoint any single plant species to devour. No crop devastation is reported so far. And no, they don’t feast on house stucco, despite the fears of one caller to a pest control agency.

And for those mindful of the biblical plagues of Egypt, these are not the kind of hoppers associated with the locust swarms of Africa.

Most of the hoppers around Los Angeles appear to be the pallid band-wing grasshopper, or Trimerotropis pallidipennis, a creature with a distinctive, pale-yellow hind wing that is common from British Columbia to South America.

Reports out of Arizona suggest that the same pallid band-wing hopper is responsible for the swarms reported there, although federal agriculture experts are conducting tests, said Michael Rethwisch, University of Arizona extension agent and entomology expert.

Although scientists can’t say for sure that the hoppers won’t attack crops, they say no major plant infestation has been reported so far.

“I don’t see there’s going to be any severe damage from these things, but, you never know,” said Jeff Knight, entomologist with the Nevada Division of Agriculture.

“Are we seeing a lot of damage from them? No. They’re flying, not because they’re hungry, but because they’re attracted to light,” Rethwisch said.

In fact, he speculates that the hardest-hit cities so far, such as Laughlin and Lake Havasu, are those that are islands of light in the dark desert. Some service stations near Blythe, where lights burned through the night, reported grasshoppers three layers deep, he said.

Some speculate that this could be the biggest burst in pallid band-wing numbers in the region since the legendary surge of 1958 in Arizona, when pilots reported grasshopper encounters at 3,000 to 5,000 feet.

The Los Angeles area--the biggest beacon of light in the desert Southwest--has not reported huge swarms of grasshoppers, but agricultural and pest control experts have been fielding calls for days on end.

Shaw, a specialist with the Orange County Vector Control District, says pesticides are not advisable, especially because of the large numbers of hoppers.

“You just have to live with them until the cycle’s over,” he said. “As the food supply dries up, they’ll die out.”

The grasshoppers’ natural food source includes a wide variety of plants.

Otte calls them relatively harmless.

“I do know that they will scare easily. I would think if they’re sitting in a bush in your garden, you can flush them out of there,” said the scientist, who has written two books on grasshoppers and is writing a third. “I think pesticides are scarier than having them chew some of your plants.”

Still, the infestation has been a boon for some desert-area bug extermination businesses. Jaime Smart, Palm Springs sales representative for Terminix, said that in recent days her office has acquired about 15 new residential customers who want the grasshoppers eradicated.

“We like it!” Smart said. “We’re into it, the more grasshoppers the better, as far as I’m concerned.”

Earlier in the day, she had to resort to a more traditional, but equally effective method, to get rid of the pesky grasshoppers.

“They have some nerve,” Smart said. “They’re all over my parking lot, and several of them flew into my office. I had to stomp them. . . . They don’t bug me, because I’m the bug lady.”

Many of the grasshoppers have been reported in parking lots, such as the one at Tustin Marketplace.

This particular creature likes bare patches of earth, not dense vegetation, experts said. That could account for its fondness for parking lots and driveways.

“A driveway is going to look more like a desert than a flower garden is,” Otte said.

But some more adventurous hoppers are venturing beyond the parking lots into buildings.

Grasshoppers annoyed several dozen potential jurors Tuesday as they waited inside the jury assembly room at the Indio courthouse, forcing them to leave.

Royann Nelson, a Riverside Court court officer, said that about 60 people summoned for jury duty had to be sent home when swarms of grasshoppers flew into the room each time the door was open.

“It was unbelievable,” said Nelson. “The grasshoppers were flying and jumping in the room. Our maintenance people had to come in and clean them out.”

Courthouse officials solved the problem by turning off the outside lights around the courthouse Tuesday night, Nelson said.

“If you want them to go away,” Rethwisch said, “turn off the lights.”

Times staff writer H.G. Reza contributed to this report.

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Pallid Band-Wing Grasshopper

(Trimerotropis pallidipennis)

Color: Grayish-brown body, short antennae. Dark-banded outer wings cover inner yellow wings.

Habitat: Western prairies, desert grasslands, deserts from southwestern Canada to central Argentina.

Life cycle: 1 1/2 months (from egg to adult)

Length: Up to 1 3/4 inches long

“Sings” by rubbing its hind leg against forewing, making wing vibrate. Many species make crackling sounds by snapping their wings during flight. Grasshoppers are most active in daylight; crickets come out at night.

Source: Brian Harris, Natural History Museum of Los Angeles County, Entomology Section