NEW ORLEANS -- The National Oceanic and Atmospheric Administration's criminal division for marine law enforcement is now investigating four dolphin deaths along the northern Gulf Coast.
At the same time, private groups have increased the reward for information leading to the conviction of their killers to $10,000.
Last week, a dolphin was found shot with a 9 mm bullet wound in the East Biloxi Channel in Mississippi. One was found dead with its tail cut off and another one had part of its jaw missing.
Dr. Moby Solangi runs the Institute for Marine Mammal Studies in Gulfport. She said dolphin tails and jaw bones have no value. They aren't bought or sold, but may have been taken by the killers as trophies.
Solangi's team conducted the necropsies, like animal autopsies, on the dolphins.
'We have seen actual saw marks on the tail being cut and the jaw being cleanly cut,' Solangi said.
'We rely, in these type of things, heavily on people giving us tips just like any other law enforcement,' said Jeff Radonski, acting deputy special agent in charge of NOAA's Law Enforcement Division.
Law enforcement officers with NOAA have investigated five dolphin shootings in the past two years: two in Mississippi and three in Louisiana. The Louisiana dolphins were found in Grand Isle, Dularge and on Elmer's Island.
'Some citizens reported a dolphin was swimming with a screwdriver in its head. It was later found without the screwdriver and deceased,' Radonski said.
Outside of facilities like the Institute on Marine Mammal Studies, dolphin and human interactions are illegal.
But people are fascinated with them, and that gives Solangi hope for justice for them.
'I think the person who has done this is probably deranged and has probably talked to somebody,' he said.
If NOAA finds who's responsible, they will face up to a year in prison and up to a $150,000 criminal fine, plus NOAA said they can also levy civil fines and penalties.
If you have any information that can help, call NOAA's law enforcement division at 800-853-1964.