Grackles could probably live on french fries, pizza crust and chips, University of Texas biology professor and longtime birder Peter English says. But it’s not because they are couch potatoes.

“They aren’t lazy,” English says. “They work really hard, but they take food that’s the easiest, but so do you. Every living thing takes the easiest route.”

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Grackles thrive because they take advantage of any free food that humans toss or leave exposed for them, from the pizza boxes left on top of a trash can downtown to the basket of chips left on a table at a restaurant.

The grackles’ diet, no matter how full of carbs and salt, has proven to give the current population an evolutionary edge. “The ones that didn’t eat the chips, they died or they had fewer babies,” English says. “A bird’s success is only measured in offspring.”

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.

Grackles don’t show a desire to eat off bird feeders, though they have been known to throw nuts on a street so the cars can run over them and crack them open. When they have young babies to feed, grackles need more protein; Travis Audubon Society volunteer Judith Bailey says that’s why you might see a female grackle pick up another bird’s nestlings to feed her babies.

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