Longboat Key turtle season affected by beach renourishment, storms

Volunteers keep an eye out for potential obstacles during a turtle nesting season that included red tide, storms, beach work and rule-breakers.

By Nat Kaemmerer
| 1:19 p.m. November 8, 2021

Longboat Key
News

In the age-old question of nature versus nurture, turtle patrollers along Longboat Key beaches tried to strike a delicate balance this year.

Nature took its toll on nests as storms and red tide rolled close to a shoreline that itself was changing throughout the summer as the town's renourishment work progressed. And humans, as they often do, didn't always follow the rules.

So, volunteers and scientists worked to make nesting turtles' paths as easy as possible. And the turtles came.

“The nourishment project, obviously, was huge, but for how big it was, things went well,” said Melissa Bernhard, a Mote Marine senior biologist in sea turtle conservation and research. “We didn't have any major issues, or anything crazy memorable. It was just like, ‘Oh, we moved nests, we put them here. We did that again the next day.’ As far as nesting numbers go, it's on par with other recent years, which are all the highest years that we've had. Overall, not just for Longboat, but for all five of the islands we look at, it was the fourth-highest nesting that we've had in our 40 years.”

Nesting females, though they were disoriented at a higher rate than normal, weren’t really affected by red tide. Though nest numbers were high, the percentage of hatched nests is a different story. Raccoons and other animals, nest relocation and storm washout conspired against healthy hatchlings.

“We had a lot of nests,” Bernhard said. “I don't know how well they did. I haven't gotten into that analysis yet, but nothing really stood out to me as the season was happening.”

Life cycle of nest

The final nest on Longboat Key was declared a washout on Nov. 1, two days before it reached 70 days. Nesting mothers lay eggs anywhere from mid-April to November. A mother crawls onto the sand, usually not far from where she was born, and if she likes the sand she feels, she’ll lay her nest. The eggs will incubate anywhere from 45-70 days, but LBKTW and Mote give each nest 70 days.

“Hopefully they get through the incubation without any or too much water damage from storms or any predator activity,” Bernhard said. “We do have a lot of, particularly, raccoons, but also armadillos and coyotes in our area and they do tend to have the taste for turtle eggs … Hopefully the nest makes it through that incubation time, and then they'll hatch.”

It’s best if the babies hatch at night, so they crawl to the brightest horizon — the moon over the ocean. About three days before they hatch, they absorb the rest of their yolk, which acts as a food sac for the hatchlings as they swim for days through the water out past the weed line.

“The best nests are the ones that we, for lack of a better word, almost forget about, because nothing happens to them,” Bernhard said. “They're just incubating, and then they hatch out, and everything's great.”

While red tide might stick out in human memory as the most memorable part of the summer, the nesting turtles might disagree. The renourishment project on Longboat Key required turtle patrollers to move each nest that was laid in a section that would be getting covered with sand soon. If patrollers found a nest, they would dig down to find each egg, gently remove it and place it in a bucket with sand from the nest.

Many nests had eggs in the 70s, but Longboat Key Turtle Watch vice president Cyndi Seamon said some had as many as 120. Those nests get wire cages over them to give them a leg up against predators after the disruption of being moved. Bernhard noted that many nests were moved out of an area with high predation in the past, but overall predation was still on par with high recent numbers.

“Depending how far we have to go we would walk them, or drive in cars or ATVs,” Seamon said. “Once we get to a location we think is a good location, we’ve taken measurement of what mama did as far as depth and width of cavity, and we dig basically the same measurements and we use the same sand we gathered from the bottom of her nest and put it in the bottom of our nest.”

In the past, Seamon said they have had a good ratio of relocation success. FWC will study the impacts of the renourishment for several years. Even though the activity is heavily permitted to try for the least disturbance, Mote will collect data on hatch success and false crawl ratios to see how nesting is impacted.

“We’re collecting hatch success and that sort of thing on both the relocated nests and the nests that are laid in that new sand afterwards,” Bernhard said. “Then it’s the next two or three years that we will continue to monitor for these to ensure that the sand that has been placed there (is suitable), and the slopes are equilibrating too and all of that is not impacting the nesting too much. There's always going to be some impact, because it's not how Mother Nature created it, but it's a matter of is this an impact that is tolerable? Or is it horrible?”

Code enforcement

The town's turtle ordinance will change in January 2022 and starting soon, code enforcement officer Chris Kopp will host public awareness classes about the changes.

But for now, the old ordinance is still in effect. Kopp, in his second year of turtle season code enforcement, hit the sand running to keep hatchling disorientations down, even though adult female incidents were up.

“This year, we got a new email address set up so that way, they (LBKTW volunteers) can start sending potential violations to me,” Kopp said. “They were coming in and they were coming in daily, which really allowed me to focus throughout those 11 miles to go look for the lights and we were able to hit them a lot more effectively and efficiently … As soon as we knew that there were potential violations, (volunteers) tell me and we tried to come fix it that night.”

More properties had employees checking beach furniture at night on their stretch of beach as well as other properties.

“The numbers of violations and inspections, I think, increased mainly because of the cooperation that we had with our volunteers,” Kopp said. “We were able to pinpoint where those potential violations are. There could be a chair out on the beach and I might not get to it for a week or two ... but this way, we were able to find out exactly where the items were. We did impound a bunch of items as well. Lounge chairs, umbrellas, signage, all kinds of things that were left out on the beach that the town felt was a safety hazard that needed to be immediately removed.”

Kopp said there were 362 total violations observed this turtle season, and 266 were lighting-related.

The nesting success is the percentage of false crawls to actual nests laid. If females are coming up the beach and leaving without nesting more often, that might have something to do with how the renourished beach feels to them, whether that means the slope or grain shape is off. Bernhard said that renourishment projects take time to settle back to the natural slope.

“It can have to do with other factors too, so they don't blindly look at that, but nesting success is big,” Bernhard said. “Then they also will look at emergence and hatch success, which is the actual number of hatchlings that hatch out of eggs, and the number of hatchlings that actually emerge from the nest, because not all are gonna make it to the surface … They take data from everywhere and say, ‘OK, which projects are more successful than others? What's the common theme between those? We're not going to allow this kind of stuff, we're going to promote this kind of nourishment,’ that sort of thing.”

Relocating nests was difficult on the north end of the beach, Seamon said. Some of the first nests they relocated on the north end suffered from the flat beach and got inundated with water. If nests are underwater for too long or get tumbled in the surf, it’s basically a death sentence. Bernhard hasn’t delved into the analysis this year, but said that nests fared better from storms than in 2020. Tropical Storm Elsa was the most impactful. About 60% of nests were impacted by the storm, but not many were lost.

“Even though a lot of them got hit by water, that didn't necessarily mean that they were killed because they have some capacity to be underwater for short periods of time during high tides,” Bernhard said. “The number we actually lost to the storm was much lower. I think it was a single digit percentage. Even though our beaches were underwater for a few days, a lot of the nests were able to survive it. It was kind of unique in that way compared to last year.”