Who is shooting and mutilating dolphins in the Gulf of Mexico, and why?

Photo: IMMS

Someone is killing and mutilating dolphins in the Gulf of Mexico, and no one can figure out who is doing this, or why. This Friday, a team from the Institute for Marine Mammal Studies (IMMS) in Gulfport, Mississippi encountered a dolphin with its lower jaw cut off; last weekend, they found a dead dolphin with a 9mm bullet wound that "went through the abdomen, into the kidneys and killed it," according to IMMS director Moby Solangi. Snip from the Sun-Herald's coverage:
In Louisiana, a dolphin was found with its tail cut off. "Animals don't eat each other's tails off," Solangi said. "We think there's someone or some group on a rampage," he said. "They not only kill them but also mutilate them."

IMMS investigated the first dolphin shooting earlier this year and incidents have increased in the past few months. In Alabama, someone stabbed and killed a dolphin with a screwdriver, according to a National Oceanic and Atmospheric Administration press release. In September, a dolphin was found on Elmer's Island, La., with a bullet in its lung. Others have been mutilated with knife-like lesions.

Read more at the Sun-Herald, more at Alabama news site AL.com, and more in the Associated Press. All of this may or may not be related to screwdriver attacks on dolphins this June. Who the hell does this?