The US Fish and Wildlife Service told local newspaper The Citrus County Chronicle the injured manatee was found on Sunday (local time) in the headwaters of the Homosassa River on the state’s west coast, about 160km west of Orlando.
Video and images show an underwater view of the slow-moving mammal, with “Trump” etched in large letters in its back.
The manner in which the letters were engraved is not clear.
Craig Cavanna, a senior wildlife officer involved in the investigation, declined to comment to the newspaper.
However, he did say harassment of a manatee is a federal criminal offence and those responsible are facing a $50,000 fine and a year in prison.
Manatees are protected under the Endangered Species Act, according to the Fish and Wildlife Service’s website.
Manatees, which live in fresh water in the Gulf of Mexico, Amazon River and the west coast of Africa, are a relative of Australia’s salt water dugongs.
Reward offered on information on ‘cruel mutilation’
The Tucson, Arizona-based Center for Biological Diversity on Monday said it was offering a $5000 reward for information “leading to a conviction for the cruel and illegal mutilation”.
“It’s clear that whoever harmed this defenceless, gentle giant is capable of doing grave violence and needs to be apprehended immediately,” Jaclyn Lopez, the non-profit group’s Florida director, said in a statement.
Manatees often seek sanctuary in the waters along Citrus County, which makes them accessible to swimmers and fishermen in boats.
Mr Cavanna told the publication the mutilation was “out of character” for the local community, which he said has a “core value of wildlife conservation”.
Anyone who knows anything about the incident is urged to contact the Florida Fish and Wildlife Conservation Commission.
Tensions have continued to bubble across the US in the week since the violent and deadly riots at the Capitol on Wednesday (local time).
Outgoing President Donald Trump is now facing a charge of “incitement of insurrection” as House Democrats push forward in their bid to oust him in the wake of the Capitol riots.
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