Meghan Lalor, Chief of Staff for NYC Parks, tells TMZ… the Urban Park Rangers are monitoring the colorful bird after the Big Apple was hit with its first snowstorm.

People were worried the non-native species would hate the freezing temps, but Park Rangers assure us they're doing everything they can to keep tabs on his health ... and he actually seemed pretty delighted by snowfall.

It's funny ... the duck sometimes leads Rangers on a wild goose chase, because it's difficult to track his every move and he often disappears for days at a time ... but the Rangers eventually find him.

We're told the duck is likely a pet that was let loose in Central Park, and Rangers are prepared to make a rescue attempt if the bird ever appears injured, in need of care, or demonstrates a change in behavior.