Mystic Aquarium officials say a dead harp seal left curbside in Providence was already deceased when it was dumped, along with a sign saying it was free to a good home.
The Connecticut aquarium says the female seal was previously found dead on an unidentified beach in the area. Scientists at the aquarium were able to match spot patterns from photographs of that seal with the one found Monday in the city's Mount Hope neighborhood.
It is a federal crime to move a protected marine mammal, living or dead.
Spokesman Skip Graf says scientists at Mystic hope to perform a necropsy to try to learn how the young, 45-pound seal died.
The man who contacted police said the seal must have been put outside his home between 11 p.m. Sunday night and 10 a.m. the next day, when it was found, WJAR reports.
A hand-written cardboard sign found with the body said, "FREE SEAL (To a good home, Naps a lot, Housebroken)."