According to the Sun Herald, the National Oceanic and Atmospheric Administration has issued a directive, putting officials on alert for an increase in human interaction with dolphins in the waters across Louisiana, Mississippi and Alabama.
Authorities say they've recently detected cases of gunshot wounds, mutilations and other injuries.
Scientists with the Institute for Marine Mammal Studies in Gulfport have responded to four cases of stranded dolphins. Friday, a team went to Deer Island and found a dolphin dead with a portion of his jaw missing.
Earlier, a dolphin was found dead near Gautier. It had a 9mm bullet wound.
"It went through the abdomen, into the kidneys and killed it," said Moby Solangi, IMMS executive director.
Solangi said recovering the dolphins and performing a necropsy to determine the cause of death is heartbreaking for his staff.
"We think there's someone or some group on a rampage," he said. "They not only kill them but also mutilate them."
The public can help by reporting any information they may know about the mutilations, he said. He also asked recreational and commercial fishermen to be on the watch for anyone killing the dolphins.
Attacks on the dolphins carry fines and jail sentences.
Solangi said he doesn't know why anyone would want to kill the dolphins, though, in the past fishermen and charter boat captains have been convicted of harming dolphins they thought were taking bait or fish.
The Associated Press contributed to this report.