A nude beachgoer chills in the water at Montrose Beach while a woman exercises. View Full Caption Luis Munoz

CHICAGO — Luis Munoz frequently visits Montrose Beach to photograph shorebirds like gulls and plovers.

But during his trips to the popular beach for birders, Munoz also usually sees naked beachgoers, on the sand, in the brush and in the water.

Tuesday morning was no exception as Munoz — a retired Chicago Police Department homicide detective and president of the Chicago Ornithological Society for the last two years — saw several naked people. That included a nude man in the water casually washing himself while a clothed woman exercised nearby on the shoreline.

Nudity is illegal at all Chicago public beaches at all times.

"Go to Montrose, and you're going to see all kinds of things," said Munoz, who lives in Uptown.

RELATED: Montrose Beach Surf Park Plan Nixed After Birders Object

When he was a policeman, Munoz would approach the naked beachgoers and tell them he was going to take a walk and they needed to have their clothes on when he returned; otherwise he would arrest them.

"I'd come back, and they'd usually be gone," he said.

Munoz said he believes the people who undress are "regular Joes" and not part of the homeless population living nearby. Uptown had the highest increase in homeless population of any Chicago neighborhood from 2015 to 2016.

Munoz said he became an avid birder because the activity helped him relax from the pressures of working the homicide beat for 22 years. In 1992, he was shot while on duty at the Rockwell Gardens housing complex.

He said seeing the naked people doesn't necessarily bother him because, "It takes a lot to shock me."

He likes going to Montrose Beach, he said, because it's a rare North Side area to see shorebirds.

"This is where I escape, and I can be in my own little world," he said.

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