This article is a hypothesis based on folklore and its potential plausibility. It is not presented as a scientific study.
Turtle nesting season has begun in Florida. A bartender, “A,” at my local watering hole is a huge turtle enthusiast. So I let “A” know that on my recent walks along the beach, I’ve seen a lot of newly roped nests sprouting up as nesting season begins.
“A” asked me how far the nest was from the water. This is something I didn’t consider and didn’t really pay attention to. She explains that many locals believe that if a hurricane season is coming, turtles will nest on the beach, further away from the waves than usual. So a nesting season where turtles lay eggs near high tides is a prediction for a quiet season.
On subsequent trips, I noticed the location of the nest on the beach. Luckily, this month we had a massive seaweed flood at the same time as the King tide. This clearly marks the high tide level making it easy to spot. Turns out every nest I’ve seen this season is just above the King tide line.
According to Florida folklore, this will be the quiet hurricane season. The incubation period of sea turtles is 30 to 90 days. A three-month advance prediction and subsequent change in nesting behavior would have enormous evolutionary advantages for breeding success.
Nests are placed further from the water than necessary, causing the eggs to become dehydrated and predation, especially on that precarious night when the baby turtles hatch and plunge into the water. Seabirds and crabs lie in wait for such events.
When the nest is placed too close to the surface of the water, there is a risk that the eggs will drown.
In order for the eggs to survive and have a chance to hatch, sea turtles must lay their eggs on the sand. When they are developing, the embryos breathe air through a membrane in the egg and so they cannot survive if they are constantly covered with water.
https://conserveturtles.org/information-sea-turtles-frequently-asked-questions/#21
as well as the risk of being swept away in a storm.
Strong wave activity can also cause beaches to erode, washing away sand. This can expose sea turtle eggs, leaving them vulnerable to drying out or being eaten. They can also destroy the nest completely, roll the eggs into the sea and drown.
Sea turtles have been around for about 150 million years. If this level of predictive accuracy for seasonal hurricane levels is somehow possible, there will be plenty of time for selective pressure to cause turtles to develop this survival advantage. Anything that turtles can use to forecast, be it currents, temperature, salinity, barometric pressure, if they can, they may have evolved to be able to do that.
We should hope this folk tale holds true, and that one day we can use the same indicators that turtles use to improve our seasonal storm forecasts, (this hasn’t been very accurate for the past few years).
HT/”A”
Appendix. Here’s a photo from last July that helps cubs get lost to the Ocean after they’ve gone the wrong way.
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