ORANGE BEACH, Ala. (AP) - An "unusual mortality event" continues for dolphins in the northern Gulf of Mexico, with more than 1,000 dolphins stranded since February 2010, far above the average numbers from 2002 to 2009.
While those deaths resulted from several different causes, officials from the National Oceanic and Atmospheric Administration (NOAA), the Alabama Marine Police and other law enforcement agencies are working together to minimize the human impact on dolphin populations in the Gulf.
As part of that effort, the Alabama Marine Police hosted a meeting last week with officials from NOAA, the U.S. Coast Guard, local authorities and about 20 dolphin tour boat captains to discuss the consequences of dolphin interaction.
Feeding a dolphin is illegal under the Marine Mammal Protection Act, enforced by NOAA. The act also makes it illegal to harass or injure any marine mammal. Harassment is defined as "any act of pursuit, torment or annoyance to the creatures."
NOAA biologist Jessica Powell said that even innocent-seeming interaction can have harmful impacts on dolphin populations. Powell showed slides of dolphins who were killed or injured by boat strikes, and said boat engine noise can confuse dolphins who rely on sound for communication and to find food. Surrounding the dolphins or trapping them between a boat and the shore can be particularly stressful.
Powell said that while dolphins are known to ride in the wake of boats, deliberately steering a boat toward a group of dolphins to induce them to ride is dangerous and disruptive to the dolphins' natural behavior.
Powell recommends that boats approach dolphins slowly, maintain a distance of at least 50 yards, observe the dolphins one at a time for periods of 30 minutes at most, and shut down the engines if the dolphin approaches the boat. Powell cited one example in Hawaii where a population of dolphins moved from one bay to another after increased human boat traffic.
NOAA enforcement officer Elizabeth Nelson said one stranded dolphin had choked to death on a cleaned sheepshead that had been fed to it backwards. Another dead dolphin washed ashore with cheese curls and hot dogs still in its stomach.
Aside from the possibility of direct injury, feeding dolphins may contribute to more harmful behavior over time, as dolphins who have been fed follow fishing boats looking for an easy meal. This makes life more difficult for fishermen, who have to protect their bait and catch from the hungry dolphins. Some fishermen have been known to use firearms and other weapons to chase off dolphins.
Multiple dolphins have been shot in Alabama and Mississippi in recent years. Last year, a dolphin in Perdido Bay died after being stabbed with a screwdriver. In 2009 Alvy Key, a fishing boat captain in Panama City Beach, was sentenced to two years in prison for intentionally trying to kill dolphins with pipe bombs. Key pleaded guilty to violating the MMPA and to possession of explosives by a convicted felon.
Maj. Scott Bannon, chief enforcement officer of the Alabama Marine Resources Division, said officers found a gun with a silencer on an unrelated search of a vessel and that the silenced weapon may have been used to target dolphins more discreetly.
A single violation of the MMPA carries a minimum fine of $5,000, but all officers present said they hope better education among boaters can cut down on the number of negative interactions between boaters and dolphins.
"Our goal is that we don't get to the criminal aspect of it," Bannon told the group of about 20 representatives from local businesses that interact with dolphins. "We'd rather you guys spread the word among yourselves."
However, Bannon said he and other local law enforcement agents are getting an increasing number of calls from the public about dolphin feeding or harassment.
"Dolphin interaction keeps moving up on my desk," he said.
While NOAA is the primary agency in charge of enforcing the MMPA, Nelson said there is a joint enforcement agreement that allows local and state law enforcement officers to cite violators of the act. Nelson said that agreement is a necessity because of NOAA's limited enforcement resources.
While dolphins are a common site in Alabama coastal waters, it's difficult to say whether their numbers are holding steady.
Ruth Carmichael of the Dauphin Island Sea Lab said it's hard to know how much populations are being affected by the UME because there is no baseline to compare. All we do is that a lot of dolphins have died in the nearly three and a half years since the unusual mortality event began.
According to NOAA statistics, 1,026 cetaceans (whales, dolphins or porpoises) have been stranded as part of the UME from the Louisiana-Texas border to Franklin County, Florida from Feb. 2010 to July 21, 2013. Of those 1,026 strandings, 512 occurred in Louisiana, 270 in Mississippi, 137 in Alabama and 109 in Florida. Ninety-five percent of the stranded animals died.
From 2002 to 2009, the average number of strandings per year in Louisiana was 20, the same as Mississippi and the Florida Panhandle. Alabama averaged 14 strandings per year over that stretch.
And the event is clearly still ongoing. April 2013 was the second-worst month for dolphins of the UME, with 66 strandings documented. Through July 21, NOAA has recorded 200 dolphin strandings in 2013, 59 more than through the same time period in 2012.
Powell said dolphins are also slow breeders, making them slow to rebound from sustained die-offs. The dolphin gestation period is about 12 months, they breed only every few years and multiple births are extremely rare.
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Large numbers of dolphins dying in Gulf
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