Both lost-and-found operations say the holiday season, when residents and millions of tourists are more rushed than usual, is the busiest (and apparently most forgetful) time of the year.
Clerks become detectives on their own, searching through coat pockets, say, for a business card they might call to locate the proper owner.
Every once in a while they also interact with repeat customers such as college student Ezra Marcus, who in October forgot his wallet on a Metro-North train, recovered it but then lost it again in November and learned this month it hadn't yet been found.
"I'm one for two," said Marcus, 21. "It's not a big deal, I canceled the debit card. ... They were able to help me out before."
For Rosario, who has worked at Metro-North's lost and found for 10 years, the wacky finds and hard-to-believe stories are popular, but the job ultimately is rewarding for giving people hope after losing items that often hold sentimental value.
"We all know how it feels to lose an item," he said, recounting the time someone claimed a scarf that had been hand-knitted by a since-deceased grandmother. "I've seen people cry when they get their stuff back and they're really, really elated."