Threats

Leatherbacks face different threats at each stage of their lives, specific to the habitats they occupy during those stages. To save the leatherback, we must reduce threats in all of the habitats turtles occupy at the various stages of their life cycle.

For example, a nest that eludes poachers may produce a hatchling lucky enough to avoid ingesting plastics as she searches for food in ocean eddies. The turtle will need to avoid entanglement in fishing gear as she migrates over long distances in search of jellyfish. If she survives the 15-25 years it will take her to reach sexual maturity and successfully finds a mate in the open ocean, she will return to her natal beach to nest. Lights along the coast or debris on the beach could deter her from nesting. The nest she lays may be washed away as sea levels rise or dug up by unleashed dogs. The eggs may be poached by collectors, eaten by raccoons, or cooked alive as beach temperatures rise. Hatchlings disoriented by lights onshore may not reach the water and face a higher risk of dehydration and predation during this critical period.

Development

Sea turtles nest on sandy beaches in the tropics and sub-tropics. People find these beaches attractive places to build beach houses, restaurants and hotels. Loss of habitat through development of nesting beaches presents one of the most serious threats to sea turtles around the world.

Coastal Construction

Coastal construction and dredging can reshape beaches, making them too steep for nesting leatherbacks to haul themselves out of the water. Construction noise can also drive turtles away. Removing beach vegetation contributes to erosion of nesting beaches and destroys critical nesting habitat for green turtles.

Cutting down shoreline trees and shrubs may improve ocean views but also permits light from beachfront buildings and streets to shine on the beach, disorienting hatchlings and deterring turtles from nesting. Human use and development of nesting beaches can also threaten turtles with pollution from septic systems, trash and pet feces.

Beachfront Property -Land cleared for real estate development at Playa Grande.

Starry Night Leatherbacks and other sea turtles prefer dark nesting beaches with no artificial lighting.

Fishing

Fishing to supply growing global demand for seafood presents a major threat to sea turtles. Fishermen targeting swordfish, tuna, shark and shrimp catch turtles unintentionally. Incidental capture and targeted fishing of sea turtles for consumption can contribute to population declines even when nesting beaches are protected.

Unable to surface to breathe, many turtles drown after becoming entangled in fishing lines or ensnared by nets. Other turtles, lured by fishing bait, become hooked and sustain injuries that can still kill them even if they are released.

The incidental capture of turtles as bycatch is underregulated and the difficulty of enforcing laws at sea creates opportunities for consumption of turtles even when they are afforded legal protections.

Nest Disturbance

Leatherbacks nest on sandy, sloped beaches with vegetation

Laws prohibit collection of sea turtle eggs in many countries, but poaching often continues in areas with weak enforcement. Costa Rican authorities allow local people to sell sea turtle eggs collected during the first three days of an olive ridley arribada (the Spanish word for a mass nesting of turtles) at the Ostional Wildlife Refuge.

Unfortunately, poachers also use this market as cover for sale of illegally collected sea turtle eggs, including critically endangered leatherback eggs.

Turtle eggs and nestlings are easy targets for predators with a strong sense of smell. But introduced species like domesticated dogs and cats are creating new threats to sea turtle nests along with natural predators, like coatimundis in Costa Rica.

Beachgoers are often unaware that walking above the high tide line or driving on the beach can crush nests and kill nestlings. Visitors pitching beach umbrellas in the sand to create shade on a sunny day may unknowingly penetrate turtle nests. Pet owners are usually unable to react fast enough to stop unleashed dogs from digging up turtle eggs.

Pollution

Pollution takes many forms and threatens sea turtles in insidious ways. Turtles looking for food mistakenly ingest plastic debris. Agricultural runoff and chemical contaminants in coastal waters make turtles more susceptible to disease. Light and noise pollution drive turtles away from critical foraging and nesting habitats.

In the ocean currents where sea turtles search for food, degraded plastic particles are now more prevalent than zooplankton. Sea turtles often swallow plastic debris, which can block digestive tracts and cause them to starve to death. Leatherbacks confuse plastic shopping bags for jellyfish, a deadly mistake. Turtles can also become entangled in ghost nets and lines, fishing gear lost or discarded in the ocean by fishermen.

Oil spills and chemical contamination of waterways can cause respiratory inflammation, gastrointestinal ulceration, organ damage and reproductive failure in sea turtles.

Turtles exposed to high levels of nitrogen from agricultural runoff and discharged sewage suffer from increased rates of fibropapillomatosis, a condition characterized by development of internal and external tumors that can ultimately lead to death.

Bacterial contamination of sand at nesting beaches prevents eggs from developing and can infect adult turtles.

Noise and light pollution also negatively impact sea turtles. Unfiltered lights in coastal areas disorient hatchlings and deter adult turtles from nesting. Persistent and abrupt low-frequency noise, including seismic tests for energy exploration, disturbs turtles and may even damage their hearing.

Climate Change

Climate change can skew sex ratios of sea turtle hatchlings, like this olive ridley.

Shifts in regional currents and global circulation patterns resulting from climate change will reshape the ability of hatchling and juvenile turtles to find food and seek safety from predators. Climate change is expected to alter the abundance and distribution of sea turtle prey via changes to sea surface temperature, salinity, oxygen and acidity. The El Niño patterns becoming more frequent as global temperatures rise are associated with negative impacts on ocean productivity.