Investigation Continues As Dolphin Deaths Rise

Sep 14, 2018
Originally published on September 14, 2018 1:35 am

The federal government, with the help of Mote Marine Laboratory, is continuing to investigate a significant spike in dolphin deaths in the Gulf of Mexico -- and they want to know if red tide is playing a part in it.

History seems to be repeating itself, as 283 dolphins died as a result of the last immense red tide bloom from 2005-2006. This time, the alarming number of dolphin deaths led the National Oceanic and Atmospheric Administration to declare what’s known as an Unusual Mortality Event.

NOAA says at least 50 dolphins have died in the Gulf since July.

Several factors are considered when a UME is declared.

“There’s seven different criteria, I think you have to meet two or three of them and we did that with the numbers that we’ve had,” said Gretchen Lovewell, Mote’s Stranding Investigations Program Manager and the on-site coordinator for the investigation.

NOAA has partnered with Mote to see what the cause may be and if there is a connection to red tide.

Lovewell and fellow researchers tested samples from the bodies of 17 recovered dolphins, and 10 tested positive for red tide neurotoxins. Larger animals, like dolphins, can be exposed to those toxins in various ways, including by the consumption of contaminated fish.

“We never want to see animals dying or dead, but we do try to make the most of an unfortunate situation and then learn as much as we can from those dead animals,” said Lovewell.

“It allows us to learn from them so that we can apply what we learn to those populations that are still out there.”

Moving forward, if the number of dolphin deaths continues to rise, Mote will work with their state partners to try and establish a budget for further help.

In addition, Mote is cooperating with groups studyng the deaths of other sea life.

"We're also going to be working really closely with our state partners that are looking at sea turtle and manatee mortalities," Lovewell said.

The Sarasota Herald-Tribune reports, since Nov. 2017, red tide is suspected of causing 965 sea turtle strandings. In addition, 127 manatee strandings were apparently caused by red tide exposure.

The deaths of a pair of pygmy killer whales who beached themselves in shallow waters off Sand Key in August are also suspected to be red tide-related.

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