What repels a plague of grackles?

Loud noises.

Lasers.

Hawks.

At least for a while.

During the 1980s, grackles roosted in great numbers among the sheltering coastal live oaks planted on the University of Texas campus by late Regent Lutcher Stark, namesake for the Stark Center for Physical Culture, located at the north end of Royal-Memorial Stadium.

A single grackle can be a thing of beauty. Alert and intelligent, they adapt easily to human ways.

WHEN GRACKLES ATTACK RUNNERS

A flock of hundreds if not thousands of grackles, on the other hand, is a menace to civilization. They "ack" and "toot" like hearty partygoers until fairly late at night. They let loose an icky gray-white liquid that not only stains and stinks, it blankets cars and buildings, creating an undeniable public health threat.

Nobody knew how to fend them off. Until it was noticed that when the Longhorn Marching Band paraded across campus, the birds scattered in terror.

"Texas Fight," indeed.

Residents of Austin have a complex relationship with great-tail grackles, which are known to flock grocery stores, restaurants and parking lots in large numbers.

So campus leaders decided to play recordings of the marching band at top volume from roving vehicles. This worked for a time.

But grackles, especially in winter, when they congregate for warmth as much as for safety and sociability, will simply meet up elsewhere. They headed downtown. They hit the H-E-B parking lots.

So entrepreneurs offered grackle-cracking sound blasts to anyone — including for quite a while, the American-Statesman— from small trucks. As early as 1997, a company called Avian Flyaway utilized what it called "non-lethal startle techniques," which meant anything from blowing horns to shaking branches.

Trouble was, you could blast only when few sensitive humans were present to be startled, too.

In Fort Worth, humans have used cannons and lasers to combat the pests. Others have tried trap-and-release methods.

Austin falconer Steve Oleson uses another trick: trained Harris hawks.

"It usually takes two or three times me coming out, but I may come back more," he told the American-Statesman in 2012 during an early morning hawk patrol on Rundberg Lane. "Whatever it takes to get rid of a problem."

And so the grackle wars rage on.

EVERYTHING GRACKLE WEEK