By Kaija Wilkinson
MOBILE, Alabama (Reuters) - Authorities are trying to determine who is responsible for killing at least six bottlenose dolphins that have washed ashore along the U.S. Gulf Coast in the past several months, in some cases with their carcasses mutilated.
In the most recent case, a dolphin was found dead Friday with part of its jaw missing on Ship Island off the Mississippi coast, said Moby Solangi, director of the Institute for Marine Mammal Studies in Gulfport, Mississippi.
Another dolphin was found a few weeks ago on Alabama's Dauphin Island with its tail cut off, Solangi said, and in June, one found near the Alabama-Florida line had been stabbed in the head with a screwdriver.
Other dolphins have been found shot in Mississippi and Louisiana, he said.
"In my 30-plus years in this business, I've never seen anything so heartbreaking, cruel and senseless," Solangi said on Tuesday. "You hear about serial killers who chop up bodies and put the parts in the freezer. This is just as horrible, but involving defenseless animals."
The institute, which performed necropsies on the dead dolphins, has provided forensic evidence such as bullet casings to area law enforcement and met with a federal investigator, Solangi said.
On Tuesday, the institute announced a $5,000 reward aimed at helping catch those who played a role in the dolphins' deaths.
Dolphins are covered by the Marine Mammal Protection Act, a 1972 law that makes killing them punishable by up to $20,000 in fines for each violation and a year in prison.
"We're hoping with publicity about a fine and jail sentence, someone who knows something will come forward," Solangi said.
Because the killings have spanned several states, authorities doubt a single person is responsible.
The National Oceanic and Atmospheric Administration has issued a directive to enforcement and protection agencies to be on the lookout for anyone harming dolphins.
The California nonprofit Animal Legal Defense Fund announced a $5,000 reward on Monday for anyone providing information that leads to the arrest and conviction of someone involved in the killings.
The organization said on Tuesday that it had already received one tip.
"We anticipate more leads as word of the reward spreads," said fund spokeswoman Lisa Franzetta.
She said while the organization was not aware of similar crimes against dolphins, there have been recent cases of fishermen killing sea lions that they perceived as competition. In 2010, a California man was sentenced to 31 days in jail and a $51,000 fine for shooting a sea lion, she said.
(Editing by Colleen Jenkins)