More than 700,000 ladybirds have been released in two New York City housing complexes in an effort to kill insects without using artificial pesticides.
Ladybirds are voracious eaters of aphids
The ladybirds, from the foothills of the Sierra Nevada in the western United States, will eat pests on the newly-landscaped Manhattan property.
The bugs can eat 50 aphids a day, and will lay more larvae in due course.
"They'll do their thing out there!" said Eric Vinje, whose company Planet Natural supplied the ladybirds.
The ladybirds, Hippodamia convergens, were scattered across the grounds of Stuyvesant Town and Peter Cooper Village on Manhattan's Lower East Side as an alternative to using chemical pesticides.
"In most cases, we reach for a can of pesticide - and we kill not only the 'bad guys,' but the 'good guys'," Mr Vinje told the Associated Press news agency.
"All we're doing here is putting more of the 'good guys' to tip the scale, to get some kind of pest population control."
After being collected in Oregon, California and Montana, the ladybirds are chilled to a semi-dormant state, until they are shipped to purchasers.
When they arrived in Manhattan, "they were lively and ready to eat anything that was not too quick for them," Mr Vinje said.
Local residents need not worry about the ladybirds swarming or infesting homes, Mr Vinje says, as this is not the aggressive Asian ladybird Harmonia axyridis.