Florida is on pace to smash the record for manatee boat deaths, with 86 struck and killed in the first six months of the year, according to Florida Fish and Wildlife Conservation Commission records.

Lee County leads the way with 21 boat kills, which is more than the next two counties combined. Brevard and Volusia have 9 each.

"More manatees and more boats are in the same area, and it can be due to high boating activity when the weather is good," said FWC spokeswoman Michelle Kerr. "Watercraft mortality has been identified as one of the major threats to manatees."

Boats killed a record 122 manatees last year. If the current pace keeps through the rest of the year, the boat death toll for this year could hit 172.

"Among known causes, watercraft-related mortality for the first half of 2019 is of unprecedented proportion and the main contributor to this year’s mortality so far," said Martine deWitt, an FWC veterinarian.

Collier County had three boat-related deaths while Martin County had one through June 30, according to FWC records.

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Last year, 824 manatees death were documented, which is just shy of the 2013 record of 830.

More than 200 of those deaths were attributed to a particularly nasty red tide that blanketed much of Southwest Florida for 16 months.

Other causes — cold stress, natural, undetermined — are close to five-year averages so far this year.

"The total number is about average of what we can expect for a year without red tide or other mass mortality events, compared to the past five years," deWitt said.

Environmental groups say the number of boat kills is troubling.

"Between the boat strikes and harmful algal blooms, Lee County is a tough place for manatees to call home," said Jacklyn Lopez, with the Center for Biological Diversity in St. Petersburg.

Pat Rose with Save the Manatee Club called the boat kill death rate "extraordinary."

"It's no way that there are that many more manatees (versus the past few years), it's boating behaviors and the weather," Rose said.

Rose said the boat kills aren't limited to one body of water.

"While there are concentrations in the Caloosahatchee and Pine Island Sound, it's really spread across the county with the 21 deaths," Rose said. "That's obviously really troubling. I think it's fully indicative that manatees are in peril, and it's going to be a constant challenge."

Manatees are found in peninsular Florida, the Caribbean, Mexico, Central America and northeastern South America.

These herbivorous marine mammals are frequent along the Southwest Florida coast, frequenting warm-water refuges in the winter and beaches and bays in the summer.

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They mostly graze on sea grass and aquatic plants, hence the sea cow nickname.

The overall population has grown in the past three decades, since manatee record keeping.

The most recent aerial count of manatees in Florida resulted in 5,777 sea cows being documented in January.

That's not a scientific population estimate but a bottom-line number that's used to better gauge mortality and survival rates over time.

Aerial surveys started in 1991, with 1,267 animals being recorded that year.

The U.S. Fish and Wildlife Service classifies the manatee as threatened, and it is also protected under the Marine Mammal Protection Act.

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Save the Manatees

Manatees are listed as threatened and protected by Florida and federal laws.

Here are some tips from the Florida Fish and Wildlife Conservation Commission for boaters and manatee watchers:

Obey posted speed zone signs while in areas known to be used by manatees.

Wear polarized sunglasses to reduce glare on the surface of the water so you can see manatees more easily.

Look for manatee "footprints," swirls or flat spots on the water created by a manatee’s tail.

Stay in deepwater channels whenever possible.

Avoid boating over sea grass beds and shallow areas where manatees are often found. Keep powerboats at least 50 feet away from manatees.

Don’t throw monofilament line, hooks or any other litter in the water; ingesting or getting entangled in debris can be fatal to manatees and other wildlife.

Don't feed or give freshwater to manatees.

Report dead or injured manatees at 888-404-3922.

Source: Florida Fish and Wildlife Conservation Commission