Trevor was something of a local celebrity in the tiny nation of Niue for being the only bird of his kind living on the island.
He had arrived in 2018, but it's unclear how he got there.
He lived in a roadside puddle during his short life, where he was regularly fed and taken care of by locals.
"He showed up in Niue in January last year after a big storm, we think he flew or blew here," said Rae Findlay, Niue's Chamber of Commerce chief and the person behind Trevor's Facebook page.
"It's assumed he came from New Zealand but it's also possible he came from Tonga or another Pacific island.
"He was a mallard duck so we called him Trevor Mallard after a local New Zealand politician, and the name stuck."
How did Trevor arrive in Niue?
During his short but happy life on Niue, Trevor lived in a large puddle.
"There are no rivers, streams or lakes here, so Trevor chose to live in a puddle," Ms Findlay told the BBC.
And though he has seen as the world's loneliest duck, it seemed he was anything but lonely.
Trevor's puddle was regularly checked on by concerned locals and even the island's fire brigade, who would fill it up if water levels got too low.