FAU Sea Turtle Experts Provide ‘Best Practices’ During Nesting Season

A newly hatched sea turtle is belly-up as it tries to get out of its nest on a beach in Palm Beach County in Southeast Florida. (Photo credit: Jay Paredes, Florida Atlantic University)

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Sea turtle nesting season, which typically takes place between March and October, is a busy time for biologists, wildlife management and others as they eagerly await signs of turtle movement in the sand. However, for many vulnerable and endangered sea turtle species, survival is an uphill battle. Loss of nesting habitat, high-traffic areas, rising temperatures and artificial lights are among the many factors working against them. 

Three internationally renowned Florida Atlantic University researchers provide “best practices” and answer some of the most frequently asked questions to help protect Florida’s nesting sea turtles and their hatchlings.

Sarah L. Milton , Ph.D., chair and professor, Department of Biological Sciences, FAU Charles E. Schmidt College of Science: Milton’s research interests are focused on environmental physiology, investigating the effects of environmental stressors on animal physiology and adaptive mechanisms of survival. Her research related to sea turtle physiology and conservation includes a variety of projects ranging from the energetics of hatchling disorientation, the impacts of climate change on turtles such as nest success, hatchling physiology, erosion and flooding, to developing therapeutic treatments for sea turtles exposed to toxic red tides.  

Jeanette Wyneken , Ph.D., professor, FAU Department of Biological Sciences: Wyneken’s research investigates the impacts of local environmental conditions on sea turtle development, sex ratios and dispersal. She has studied sea turtles for more than 30 years. Her research focuses on a range of areas such as how weather and climate affect sea turtle eggs and rookeries to best practices in wildlife management. Her long-term studies of nest temperatures and primary sex ratios demonstrate how species differ in their responses to changing climate and weather conditions. Her approaches include understanding what is normal, functional morphology, ecology, ethology, physiology, and developmental biology in the contexts of conservation.

Annie Page , DVM, Ph.D., associate research professor and clinical veterinarian, FAU Harbor Branch Oceanographic Institute: Page’s research interests include epidemiology, pathogenesis, eco-immunology and ecology of diseases affecting marine organisms. Her most recent research project addressed fundamental questions on characteristics of subclinical infection and transmission of chelonid fibropapilloma-associated herpesvirus infection. Page’s expertise includes wildlife medicine and rehabilitation, molecular diagnostics, disease ecology and veterinary pathology as well as conservation biology, environmental and public health, microbiology, immunology, toxicology and genomics.

Frequently Asked Questions:

• What species of sea turtles can we expect to see in Southeast Florida?

There are five species of sea turtles in Florida waters: green turtle, leatherback, loggerhead, Kemp’s ridley, and hawksbill. The most common sea turtles in Southeast Florida are green, loggerhead and leatherback turtles, which also regularly nests on our beaches.

• Which of these species are considered threatened or endangered?

All five of these species are protected species. The loggerhead and green turtles are listed as threatened and leatherback, hawksbill and Kemp’s ridley are listed as endangered.

• What should I do if I see a nest with eggs in it?

Sea turtle nests are protected by state and federal laws. Do not touch a nest on the beach. You may contact the nearest local nature center such as Gumbo Limbo Nature Center or the Loggerhead Marinelife Center for additional information.

• What should I do if I see a sea turtle laying eggs or nesting?

Keep your distance, do not touch her, and remain quiet. Do not approach her and do not use any lights. You do not want to startle her and interrupt this process. 

• If I encounter a hatchling that is struggling to get out of the nest, should I help it?

Do not touch or help the hatchling. It is against state and federal law to remove the hatchling from its natural environment. Turtle hatchlings all dig out of their nest, usually at night, and head directly for the sea.

• Who should I contact if I see an injured or stranded sea turtle or hatchling?

Call the Florida Fish and Wildlife Conservation Commission Division of Law Enforcement at 1-888-404-FWCC or *FWC from your cell phone.

• How many eggs do sea turtles lay?

During nesting season, sea turtles usually lay between four and 10 clutches, with each clutch containing between 70 and 140 eggs, depending on the species.

• How long does it take for an egg to hatch?

The incubation period for sea turtle eggs depends upon the local incubation temperatures, such that cooler temperatures can lead to incubation of more than two months. During warmer periods, nests can hatch in as little as 45 days.

• How many hatchlings actually survive and make it into the ocean?

On average, about one in 1,000 sea turtle hatchlings survive to adulthood. The others serve a different ecological role and often become prey for many other organisms.

• How long does it take sea turtle hatchlings to crawl into the sea?

Typically, sea turtle hatchlings take about 10 to 30 minutes to make their way from the nest to the sea. However, this timing varies and depends on factors such as the distance from the nest to the water, if obstacles occur in their path and if artificial lighting is present that might attract them away from the water, as well as other environmental conditions.

• Does this extreme heat we are experiencing impact sea turtle nests and hatchlings?

Yes. Extreme heat can have detrimental effects on sea turtle nests and hatchlings, impacting their reproductive success and survival. Fewer eggs hatch at high temperatures, and hatchlings are less physically adept and may have developmental deformities. High temperatures also can skew the sex ratio of hatchlings, highly female biased sex ratios and imbalance in the population and can cause nest failure by overheating the eggs.

• Where and when can I safely experience sea turtle nesting season in Southeast Florida?

Nesting season in Southeast Florida typically occurs from March through October, with peak activity between May and July. There are many places that offer guided “turtle walks” so people can safely experience nesting at protected wildlife refuges and sanctuaries such as Gumbo Limbo Nature Center in Boca Raton, Loggerhead Marinelife Center in Juno Beach, John D. MacArthur Beach State Park on Singer Island, several organizations on Hutchinson Island, and at the Archie Carr National Wildlife Refuge along the Atlantic coast.

• What do sea turtles eat?

Sea turtles do not feed on land. Their diets depend on the species and the life stage. Hatchlings tend to feed on very small, slow-moving marine animals when on the high seas. When sea turtles return years later to coastal waters, their diets differ. For example, green turtles have a vegetarian diet and prefer sea grass and algae. Leatherbacks feed primarily on jelly animals like jellyfish and salps, while loggerheads and Kemp’s ridleys prefer hard-shelled organisms such as crabs, lobsters, and mollusks, such as whelks. Hawksbills feed on algae, sponges, and tunicates on their reefs. However, all species are known to be attracted to fishing baits, a behavior that puts the sea turtles at risk.

• If I want to take pictures at night of nesting sea turtles, can I do that using a red flashlight?

Do not photograph or video a nesting sea turtle at night and do not use any lights including a red flashlight. Special permits are required to photograph or film nesting sea turtles. The Florida Fish and Wildlife Conservation Commission is the authority that issues permits for activities involving marine turtles in Florida, including photography.

• How does a hatchling know where to go when it emerges from its nest?

Sea turtle hatchlings possess remarkable instincts that guide them toward the sea once they emerge from their nest. Hatchlings crawl away from tall dark horizons (these are typically landward) and toward more open, somewhat brighter horizons, which are usually seaward. 

• Why do we have to turn off our lights at night along the coast during nesting season?

Adult females avoid lighted beaches for nesting and emerging hatchlings often become disoriented by lighting on the beach. Artificial light causes abnormal behavior such that hatchlings are misdirected as they try to reach the ocean (just like moths that get attracted to lights at night). Lights need to stay off at night so sea turtles can safely use the beach.

• Do other animals eat sea turtles?

Sea turtle eggs, hatchlings and older turtles are subject to many threats both on land and at sea. Common land predators include crabs, large lizards, birds, coyotes, foxes, and raccoons on land. Carnivorous fish such as snapper, tarpon, mahi mahi, sharks, and even marine mammals, are threats at sea.

• How is the sex of sea turtles determined?

The sex of sea turtles is determined by the temperature at which the eggs incubate. This process is referred to as “temperature-dependent sex determination.” Higher temperatures result in more female hatchlings and lower temperatures result in more male hatchlings.

• Are our Florida sea turtles healthy?

The health of Florida sea turtles can vary depending on various factors such as habitat conditions, pollution levels, climate change impacts and human activities. In general, a sea turtle that is able to reproduce is healthy. When just one in 1,000 hatchlings reach adulthood, many individuals are lost to misadventure, but also exposure to both acute, as well as chronic, challenges to their health can occur. 

• What are some of the most common diseases we are seeing in Florida sea turtles?

In Florida, sea turtles face various health challenges such as fibropapillomatosis, a viral disease that causes the growth of tumors on the skin, eyes and internal organs. This condition is particularly prevalent in green sea turtles. Sea turtles also are impacted by debilitating internal parasites as well as external parasites like barnacles and leeches that can attach to a sea turtle’s shell, skin or flippers, potentially impacting their ability to swim and feed. In addition, ingestion of marine debris such as plastics and other jetsam mistaken for food can lead to blockages, internal injuries, toxic effects and malnutrition.

• What can I do to help protect Florida’s sea turtles?

There is a combination of actions you can take to protect Florida’s sea turtles and support broader conservation efforts. These include educating yourself and your networks about reducing light pollution, participating in beach cleanup efforts, respecting nesting areas, reefs and feeding areas, minimizing the use of single use plastics, reducing your carbon-footprint to help reduce greenhouse gas emissions, properly disposing of fishing gear, supporting conservation organizations, and advocating for effective policy changes. By taking these steps, you can contribute to the conservation of Florida’s sea turtles and help ensure their survival for future generations.

-FAU-

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