NEW YORK – At first light, the pink flamingos stretch their spindly legs, the Inca terns burst into flight, and the penguins plunge into their pool. Soon, the air fills with squawks and honks, trills and warbles as hundreds of birds at the Bronx Zoo start their day.

By 8 a.m., they are ready for Jeremy Sanders. The bald eagles usually notice him first. They call out to him. He whistles back and smiles.

Sanders has spent nearly 18 years at the zoo, most of his adult life. In the lexicon of the zoological world, he is a senior wild animal keeper. (That is zookeeper to you and me.) And the up-close contact with the birds he cares for is the best part of his workday.

By the time many of you crawl out of bed, Sanders will be out greeting the storks, the scarlet ibises and the tufted puffins. He will be feeding the birds and assessing their well-being as he braces for the crowds that flock to the zoo during its busiest season.

“We work at the zoo for one reason,” said Sanders, who is one of 98 wild-animal keepers at the zoo. “This great love for the animals.”

“People say, ‘Wow! What a great job!’ And it is,” the bearded, bespectacled Sanders, 40, said as he walked me through his daily routine last week. “But like any job, it has its ups and downs.

“The majority of the work we’re doing is cleaning,” he explained. “You’re constantly cleaning. It’s not the most glorious part of the job, but it’s something we all accept. Our job is to take the place of Mother Nature.”

In the wild, the winds and rains cleanse the rocks and boulders, replenish the ponds and rivers and turn the sand and soil. In the zoo, those tasks fall to the zookeepers.

They scrub and hose down bird droppings from the exhibits. They drain pools and ponds to prevent the growth of algae and wash scores of food pans. They haul trees and boulders. They mow during the summer and shovel in the winter. (The penguins, who hail from South America, are no fans of snow.)

The work - which pays $34,900 a year for new hires and $48,100 for senior employees – is often hot, dirty and physically exhausting. But there are remarkable perks, including the proximity to some of the world’s most exotic creatures.

“The unconditional love, the willingness to please,” said Kathleen MacLaughlin, a senior wild-animal keeper in the zoo’s JungleWorld attraction, describing why she has stuck around for 33 years, working with gibbons, tree kangaroos and other animals. “When they like you, they give you so much back.”

For Sanders, who was born in the Bronx and often visited the zoo as a child, it was hard to envision a better fit. After studying biology and wildlife management in college, he was a manager at a pet store before landing his dream job.

He learned the life cycles of his charges, watching them hatch and grow and mourning their deaths. He learned to build nests, to search for signs of illness and to mimic the birds’ calls. In a highlight of his career, he and a colleague helped to monitor the incubation and hatching of a penguin’s egg in 2010.

He still remembers the text he sent when he saw that newborn penguin chick for the first time: “This is why we get up in the morning.”