Loggerhead Turtle
Loggerhead Turtle
Caretta caretta
Protected Status
ESA Endangered
North Pacific Ocean DPS
ESA Endangered - Foreign
Mediterranean Sea DPS,
Northeast Atlantic Ocean DPS,
North Indian Ocean DPS,
South Pacific Ocean DPS
ESA Threatened
Northwest Atlantic Ocean DPS
ESA Threatened - Foreign
South Atlantic Ocean DPS,
Southeast Indo-Pacific Ocean DPS,
Southwest Indian Ocean DPS
CITES Appendix I
Throughout Its Range
Quick Facts
Weight
Up to 250 pounds (113 kg)
Lifespan
Unknown but long-lived
Length
3 feet (90-100 cm)
Threats
Harvest,
Entanglement,
Marine debris,
Disease,
Chemical pollution,
Noise,
Habitat degradation and loss
Location
New England/Mid-Atlantic,
Pacific Islands,
Southeast,
West Coast,
Foreign
About the Species
Loggerheads are the most abundant species of sea turtle found in U.S. Atlantic coastal waters. The species is named for its relatively large head, which support powerful jaw musculature and enables them to feed on hard-shelled prey, such as whelks and conch.
All loggerhead turtle populations are listed as endangered or threatened under the Endangered Species Act (ESA). The biggest threats facing loggerhead turtles are bycatch in fishing gear, loss and degradation of nesting habitat, vessel strikes, and entanglement in marine debris.
NOAA Fisheries and our partners are dedicated to conserving and rebuilding turtle populations worldwide. We use a variety of innovative techniques to study, protect, and recover these threatened and endangered animals. We engage our partners as we develop regulations and recovery plans that foster the conservation and recovery of loggerheads and their habitats.
Status
Loggerheads are found worldwide primarily in subtropical and temperate ocean waters. Nine Distinct Population Segments of loggerhead sea turtles are listed under the Endangered Species Act. The most recent reviews show that only two loggerhead nesting beaches have greater than 10,000 females nesting per year: South Florida and Oman. The status of the Oman nesting colony has not been evaluated recently.
The loggerhead is the most common sea turtle in the southeastern U.S. They nest primarily along the Atlantic coast of Florida, South Carolina, Georgia, and North Carolina and along the Florida and Alabama coasts in the Gulf of Mexico. Total estimated nesting in the U.S. is approximately 68,000 to 90,000 nests per year.
The Cape Verde Islands off the coast of West Africa support a medium-sized loggerhead nesting assemblage. In 2000, researchers tagged over 1,000 nesting females on just 3.1 miles of beach on Boa Vista Island (an island in Cape Verde). Brazil also supports a medium-sized loggerhead nesting assemblage. There are about 4,000 nests per year in Brazil. Loggerhead nesting throughout the Caribbean is sparse.
In the Mediterranean, loggerhead nesting is confined almost exclusively to the eastern portion of the Mediterranean Sea. The main nesting assemblages occur in Cyprus, Greece, and Turkey. However, small numbers of loggerhead nests have been recorded in Egypt, Israel, Italy, Libya, Syria, and Tunisia. Based on the recorded number of nests per year in Cyprus, Greece, Israel, Tunisia, and Turkey, loggerhead nesting in the Mediterranean ranges from about 3,300 to 7,000 nests per season.
Loggerheads nest throughout the Indian Ocean and, with the exception of Oman, the number of nesting females is small. Oman hosts the second largest nesting assemblage of loggerheads in the world, recent trends analyses indicate this important nesting population is declining.
Loggerhead populations in Honduras, Mexico, Colombia, Israel, Turkey, Bahamas, Cuba, Greece, Japan, and Panama have been declining. This decline continues and is primarily attributed to bycatch in fishing gear, direct harvest, coastal development, increased human use of nesting beaches, and pollution.
In the Pacific, there are two distinct population segments (DPS) of loggerheads. The North Pacific Loggerhead Turtle DPS nests only on the coasts of Japan. This population has declined 50 to 90 percent during the last 60 years, however the overall nesting trend in Japan has been stable or increasing over the last decade. The South Pacific loggerhead turtle DPS nests primarily in Australia with some nesting in New Caledonia. In 1977 about 3,500 females may have nested in the South Pacific —today there are only around 500 per year.
The 2009 status review of the loggerhead sea turtle provides additional population information for each distinct population segment.
Protected Status
ESA Endangered
- North Pacific Ocean DPS
ESA Endangered - Foreign
- Mediterranean Sea DPS
- Northeast Atlantic Ocean DPS
- North Indian Ocean DPS
- South Pacific Ocean DPS
ESA Threatened
- Northwest Atlantic Ocean DPS
ESA Threatened - Foreign
- South Atlantic Ocean DPS
- Southeast Indo-Pacific Ocean DPS
- Southwest Indian Ocean DPS
CITES Appendix I
- Throughout Its Range
Appearance
Loggerhead turtles have large heads with powerful jaws. The top shell (carapace) is slightly heart-shaped and reddish-brown in adults and sub-adults, while the bottom shell (plastron) is generally a pale yellowish color. The neck and flippers are usually dull brown to reddish brown on top and medium to pale yellow on the sides and bottom. Hatchlings are dark in color but lack the reddish-brown coloration of adults and juveniles. Their flippers are dark gray to brown above with white to white-gray margins. The coloration of the bottom shell is generally yellowish to tan.
Behavior and Diet
Loggerheads generally prefer high energy, relatively narrow, steeply sloped, coarse-grained beaches for nesting.
Immediately after hatchlings emerge from the nest, they begin a period of high activity and continue swimming away from land for up to several days. Post-hatchling loggerheads take up residence in areas where surface waters converge to form local downwellings. These areas are often characterized by accumulations of floating material, such as algae/seaweed. Post-hatchlings within this habitat are low-energy float-and-wait foragers that feed on a wide variety of floating items, which unfortunately includes plastic.
Once individuals get transported by ocean currents farther offshore, they have entered the oceanic zone. Loggerheads spend the first 7 to 15 years (average 12 years) of their lives in the open ocean and then migrate to nearshore coastal areas. In addition to providing critically important habitat for juveniles, the coastal areas also provide foraging habitat, inter-nesting habitat, and migratory habitat for adult loggerheads.
The main foraging areas for western North Atlantic adult loggerheads are found throughout the relatively shallow continental shelf waters of the United States, Bahamas, Cuba, and the Yucatán Peninsula, Mexico. Migration routes from foraging habitats to nesting beaches (and vice versa) for a portion of the population are restricted to the continental shelf, while other routes involve crossing oceanic waters to and from the Bahamas, Cuba, and the Yucatán Peninsula. Seasonal migrations of adult loggerheads along the mid- and southeast U.S. coasts have also been documented.
Through satellite tracking, researchers have discovered that loggerheads in the Pacific have a highly migratory life stage. Hatchlings enter the ocean and undertake a trans-Pacific developmental migration from nesting beaches in Japan and Australia across the Pacific to feeding grounds off the coast of Baja California, Mexico, Peru and Chile—nearly 8,000 miles! They spend many years (possibly up to 20 years) growing to maturity and then migrate back to their natal beaches (where they originally hatched) in the Western Pacific ocean to mate and nest and live out the remainder of their lives.
Loggerheads are carnivores, only occasionally consuming plant material. In the Atlantic and Gulf of Mexico hatchlings feed on small animals living in floating seaweed called Sargassum, where they spend their early developmental years. Juveniles and adults eat mostly bottom dwelling invertebrates such as whelks, other mollusks, horseshoe crabs, and sea urchins. Their powerful jaws are designed to crush their prey.
Where They Live
Loggerheads are found throughout the temperate and tropical regions of the Atlantic, Pacific, and Indian Oceans. Nine Distinct Population Segments of loggerhead sea turtles are listed under the Endangered Species Act.
In the Atlantic, the loggerhead turtle's range extends from Newfoundland to as far south as Argentina. They are the most abundant species of sea turtle found in U.S. coastal waters of the Atlantic Ocean. During the summer, nesting occurs primarily in the subtropics. Although the major nesting concentrations in the U.S. are found from North Carolina through southwest Florida, minimal nesting occurs outside of this range westward to Texas and northward to Virginia. Adult loggerheads make extensive migrations between foraging areas and nesting beaches. During non-nesting years, adult females from U.S. beaches are distributed in waters off the eastern United States and throughout the Gulf of Mexico, Bahamas, Greater Antilles, and the Yucatán Peninsula, Mexico.
The majority of loggerhead nesting occurs in the western rims of the Atlantic and Indian Oceans. The loggerhead nesting aggregations in Oman, the United States, and Australia account for about 88 percent of nesting worldwide.
In the southeastern United States, about 80 percent of loggerhead nesting occurs in six Florida counties—Brevard, Indian River, St. Lucie, Martin, Palm Beach, and Broward. Within those counties a 20 mile section of coastline from Melbourne Beach to Wabasso Beach comprises the Archie Carr National Wildlife Refuge, which is the most important nesting area for loggerhead turtles in the western hemisphere. Twenty-five percent of all loggerhead nesting in the United States occurs in the refuge - 1,000 loggerhead nests per mile have been documented in some parts of the refuge.
In the eastern Pacific, loggerheads have been reported in waters as far north as Alaska, and as far south as Chile. In the United States, occasional sightings are reported from the coasts of Washington and Oregon, but most records are of juveniles off the coast of California. The west coast of Mexico, including the Baja Peninsula, provides critically important developmental habitats for North Pacific juvenile loggerheads which nest only in Japan. The South Pacific loggerhead turtle nests only in Australia and New Caledonia, and juveniles can be found foraging off the coast of Peru and Chile.
World map providing approximate representation of the loggerhead turtle's range.
Lifespan & Reproduction
Loggerhead sea turtles are long-lived and could live to 70-80 years or more. Female loggerheads reach maturity at about 35 years of age. Every 2 to 3 years they mate in coastal waters and then return to nest on their natal beach (where they hatched).
In the northern hemisphere mating occurs in late March to early June and females lay eggs between late April and early September. Females lay three to five nests, sometimes more, during a single nesting season. The eggs incubate approximately two months and hatch between late June and mid-November.
Threats
Bycatch in Fishing Gear
The greatest cause of decline and the continuing primary threat to loggerhead turtle populations worldwide is bycatch in fishing gear, primarily in trawls, longlines, and gillnets, but also in pound nets, traps and pots, and dredge fisheries.
Intentional Killing of Turtles
Sea turtles have been killed for their meat and skin for hundreds of years. Loggerheads are fully protected in many places where they occur throughout the world, but they are still killed for their meat in some places and this remain a serious and continuing threat to their recovery.
Ocean Pollution/Marine Debris
Sea turtles can become entangled in marine debris such as discarded fishing line or nets and discarded plastics and rope, and can be killed or seriously injured. They also ingest fishing line, balloons, plastic bags, plastic pieces, or other plastic debris which they can mistake for food; this can lead to serious injury and death.
Scientific Classification
| Kingdom | Animalia | Phylum | Chordata | Class | Reptilia | Order | Testudines | Family | Cheloniidae | Genus | Caretta | Species | caretta |
|---|
What We Do
Conservation & Management
Since 1977, NOAA Fisheries and U.S. Fish and Wildlife Service (U.S. FWS) have shared jurisdiction for recovery and conservation of sea turtles listed under the ESA. A Memorandum of Understanding outlines our specific roles: we lead the conservation and recovery of sea turtles in the marine environment, and U.S. FWS has the lead for the conservation and recovery of sea turtles on nesting beaches.
NOAA Fisheries is committed to the protection and conservation of the loggerhead sea turtle by:
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Working with our partners to enact national and state laws to protect sea turtles.
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Cooperating with international partners to implement conservation measures and establish agreements, such as international treaties.
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Researching, developing, and implementing fishing gear modifications (e.g., turtle exclusion devices for trawls, longline fishing gear technologies, and changes to gillnets ) to reduce bycatch, proposing changes to fishing practices, and closing certain areas to fishing when necessary.
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Designating critical habitat areas essential for the conservation of leatherback turtles.
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Protecting and monitoring leatherback sea turtle populations.
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Understanding migratory habitats and at-sea threats to better implement conservation measures that promote recovery.
Science
We fund research projects and conduct various research activities on the biology, behavior, and ecology of the loggerhead sea turtle. The results of this research are used to inform conservation management decisions and enhance recovery efforts for this imperiled species. Our work includes:
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Population monitoring through ship-based or aerial surveys, nesting beach studies, data, tagging and genetic studies, and mark-recapture studies.
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Studying foraging and reproductive behavior.
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Tracking of individuals over time to understand important aspects of their life history such as growth and age to maturity.
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Gleaning life history and population health information from stranding and fisheries bycatch datasets.
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Understanding impacts of change in environmental and ocean conditions on sea turtle abundance, distribution, and demographics.
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Designing fishing gear to minimize incidental capture of sea turtles during commercial and research fishing operations.
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Capacity building and training to share the latest scientific techniques and tools to monitor sea turtle populations globally.
How You Can Help
Reduce Ocean Trash
Entanglement is major cause of injury and death for sea turtles. Reduce marine debris that may entangle or be accidentally eaten by sea turtles.
Participate in coastal clean-up events.
Reduce plastic use to keep our beaches and oceans clean—carry reusable water bottles and shopping bags.
Refrain from releasing balloons—they can end up in the ocean where sea turtles can mistake them for prey like jellyfish.
Keep Your Distance
Admire sea turtles from a respectful distance by land or sea—a minimum of 50 yards (1/2 a football field)—and follow these guidelines:
Don’t disturb nesting turtles, nests, or hatchlings. If interested, attend organized sea turtle watches that know how to safely observe sea turtles.
Never feed or attempt to feed sea turtles as it changes their natural behavior and may make them more susceptible to harm.
In some places in the world, most notably Hawaii, sea turtles bask out of the water—do not disturb basking turtles sleeping on the beach, or try to push them back into the water.
Boat strikes are a serious threat to sea turtles. When boating, watch for sea turtles in the water, slow down and steer around them. If you encounter them closer than 50 yards, put your engine in neutral to avoid injury.
Protect Sea Turtle Habitat
Beaches are paramount for healthy sea turtle populations since females come to the shore to deposit their eggs into nests.
Keep nesting beaches dark and safe at night. Turn off, shield, or redirect lights visible from the beach—lights disorient hatchlings and discourage nesting females from coming onto beaches to lay their eggs.
After a day at the beach, remove recreational beach equipment like chairs and umbrellas so sea turtles are not turned away. Also, fill in holes and knock down sandcastles before you leave—they can become obstacles for nesting turtles or emerging hatchlings.
Do not drive on sea turtle nesting beaches—vehicles can deter females from nesting, directly strike hatchlings and nesting turtles, and damage incubating nests.
Report Marine Life in Distress
If you see a stranded, injured, or entangled sea turtle, make sure professional responders and scientists know about it and can take appropriate action. Numerous organizations around the country are trained and ready to respond.
Learn who you should contact when you encounter a stranded or injured marine animal >
Featured News
Related Species
Management Overview
Loggerhead turtles are protected under the Endangered Species Act (ESA). Nine populations are listed as endangered or threatened under the Act. This means that the loggerhead turtle is in danger of extinction, now or in the foreseeable future, throughout all or a significant portion of its range. NOAA Fisheries is working to protect this species in many ways, with the goal that populations will increase worldwide.
In the United States, NOAA Fisheries and the U.S. Fish and Wildlife Service (U.S. FWS) have joint jurisdiction for sea turtles, with NOAA having the lead in the marine environment and U.S. FWS having the lead on the nesting beaches. Both federal agencies, along with many state agencies and international partners, have issued regulations to eliminate or reduce threats to sea turtles, while working together to recover them.
Recovery Planning and Implementation
Recovery Action
To help identify and guide the protection, conservation, and recovery of sea turtles, the ESA requires NOAA Fisheries and U.S. FWS to develop and implement recovery plans, in close coordination with stakeholders, for each listed sea turtle species. Recovery plans provide a blueprint for conservation of the species and measurable criteria to gauge progress toward recovery.
The major recovery actions for loggerhead sea turtles include:
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Protecting turtles on nesting beaches.
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Protecting nesting and foraging habitats.
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Reducing bycatch in commercial and recreational fisheries.
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Reducing the effects of entanglement and ingestion of marine debris.
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Working with partners internationally to protect turtles in all life-stages in foreign waters.
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Supporting research and conservation projects consistent with Recovery Plan priorities.
Two recovery plans have been developed to recover and protect loggerhead turtle populations. Each is focused on the unique needs of turtles in the various regions:
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Recovery Plan for the Northwest Atlantic Population of Loggerhead Sea Turtle
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Recovery Plan for the U.S. Pacific Populations of Loggerhead Sea Turtle
The highly migratory behavior of sea turtles makes them shared resources among many nations, so conservation efforts for sea turtle populations in one country may be jeopardized by activities in another. This means that protecting sea turtles on U.S. nesting beaches and in U.S. waters alone is not enough to ensure the continued existence of the species. Learn more about international conservation efforts below.
Critical Habitat
When NOAA Fisheries lists a species under the ESA, we must determine whether there are areas of habitat that are essential, or contain features that are essential, for the conservation of the species. Those areas may be designated as "critical habitat." A critical habitat designation does not set up a marine preserve or refuge. Critical habitat protections only apply when federal funding, permits, or projects are involved.
NOAA Fisheries and the U.S. Fish and Wildlife Service designated critical habitat for the Northwest Atlantic distinct population segment for loggerhead sea turtles in waters and beach habitat of the Gulf of Mexico and along the coast of the U.S. Atlantic Ocean.
Specific areas designated include 38 occupied marine areas within the range of the Northwest Atlantic Ocean distinct population segment of loggerhead turtles. These areas contain combinations of nearshore reproductive habitat, winter areas, breeding areas, migratory corridors, and Sargassum habitat.
View the loggerhead sea turtle marine critical habitat maps
The U.S. Fish and Wildlife Service addressed approximately 685 miles of nesting beaches in North Carolina, South Carolina, Georgia, Florida, Alabama, and Mississippi in a separate rulemaking.
Conservation Efforts
Reducing Bycatch
To reduce the bycatch of sea turtles in commercial fisheries, we have enacted regulations to reduce bycatch in certain U.S. commercial fishing gears (gillnets, longlines, pound nets, scallop dredges, and trawls) that accidentally catch sea turtles. Measures include:
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Gear modifications.
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Changes to fishing practices.
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Time/area closures.
In the Gulf of Mexico, NOAA Fisheries has worked closely with the shrimp trawl fishing industry to develop turtle excluder devices (commonly called TEDS) to reduce the mortality of sea turtles incidentally captured in shrimp trawl gear. TEDs that are large enough to exclude even the largest sea turtles are now required in shrimp otter trawl nets.
Since 1989, the U.S. has prohibited the importation of shrimp harvested in a manner that adversely affects sea turtles. The import ban does not apply to nations that have adopted sea turtle protection programs comparable to that of the U.S. (i.e., require and enforce the use of TEDs) or to nations where bycatch in shrimp fisheries does not present a threat to sea turtles (for example, nations that fish for shrimp in areas where sea turtles do not occur). The U.S. Department of State is the principal agency of this law, while we serve as technical advisor. We provide extensive TED training throughout the world.
We are also involved in cooperative gear research projects, implementation of gear technologies to reduce bycatch, and safe handling protocols designed to reduce sea turtle bycatch and mortality in the Gulf of Mexico and Atlantic pelagic longline fisheries, the Hawaii-based longline fisheries, the Atlantic sea scallop dredge fishery, the Chesapeake Bay pound net fishery, and non-shrimp trawl fisheries in the Atlantic and Gulf.
Fisheries Observers
Bycatch in fishing gear is the primary human-caused source of sea turtle injury and mortality in U.S. waters. The most effective way to learn about sea turtle-fishery interactions is to place observers aboard fishing vessels. Under the ESA, NOAA Fisheries identifies commercial and/or recreational fisheries in the Atlantic Ocean, Gulf of Mexico, and Pacific Ocean that are required to have observers to record sea turtle interactions. The purpose of observing these fisheries is to:
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Learn more about sea turtle bycatch
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Evaluate measures to reduce fisheries impacts/bycatch of protected sea turtles.
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Determine whether additional measures may be necessary to prevent sea turtle bycatch.
NOAA Fisheries determines which fisheries are required to carry observers to monitor potential interactions with sea turtles through an annual determination. Observers may also be placed on fisheries through our authorities under the Magnuson-Stevens Act.
Sea Turtle Stranding and Response
A stranded sea turtle is one that is found on land or in the water dead, injured, sick, or exhibiting usual behavior. One of the most well-known examples of mass strandings is when cold-stunned sea turtles strand during winter months on the Atlantic and Gulf coasts. During these events, thousands of turtles may require care.
The Sea Turtle Stranding and Salvage Network was established in response to the need to better understand the threats sea turtles face in the marine environment, to provide aid to stranded sea turtles, and to salvage dead sea turtles that may be useful for scientific and educational purposes. The network collects information on and documents strandings of marine turtles along the U.S. Gulf of Mexico and Atlantic coasts and includes federal, state, and private partners. This information is compiled into a centralized database.
NOAA’s Pacific Islands Fisheries Science Center’s Marine Turtle Biology and Assessment Program rehabilitates and studies stranded sea turtles throughout the Hawaiian Islands. Other state and local organizations respond to sea turtle strandings on the U.S. West Coast.
The actions taken by stranding network participants improve the survivability of sick, injured, and entangled turtles while also helping scientists and managers expand their knowledge about threats to sea turtles and causes of mortality.
International Conservation
The conservation and recovery of sea turtles requires international cooperation and agreements to ensure the survival of these highly migratory animals. We have a broad national and international program and work closely with partners under two international environmental agreements that deal exclusively with sea turtle conservation:
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Indian Ocean - South-East Asian (IOSEA) Marine Turtle Memorandum of Understanding
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Inter-American Convention (IAC) for the Protection and Conservation of Sea Turtles
Additional international treaties and agreements include:
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Convention on International Trade in Endangered Species (CITES): Listed in Appendix I, which prohibits international trade of wild flora and fauna.
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Cartagena Convention: Protected under Annex II of the Specially Protected Areas and Wildlife (SPAW) Protocol.
Regulatory History
The loggerhead turtle was first listed under the ESA as threatened throughout its range in 1978. In 2011, NOAA Fisheries and the U.S. FWS determined that the loggerhead sea turtle was composed of nine distinct population segments (DPS) that constitute ‘‘species’’ that may be listed as threatened or endangered under the ESA—four DPSs were listed as threatened and five were listed as endangered. The 2009 status review provided the scientific basis to revise the ESA listings.
In 1992, we finalized regulations to require turtle excluder devices in shrimp trawl fisheries to reduce interactions between turtles and trawl gear. Since then, we have improved these regulations as new information became available on increasing the efficiency of TEDs. For example, newer regulations provide for the exclusion of large turtles that could not fit through the openings of earlier TED designs. TEDs are also required in the summer flounder fishery in certain areas along the Atlantic coast of the US.
We have implemented additional measures to reduce sea turtle interactions in fisheries through regulations and permits under both the ESA and Magnuson-Stevens Fishery Conservation and Management Act including the use of large circle hooks in longline fisheries, time and area closures for gillnets, and modifications to pound net leaders and Atlantic sea scallop dredges.
See all regulations to protect sea turtles.
Regulatory Actions & Documents
Final Annual Determination for 2019
NOAA Fisheries will not identify additional fisheries to observe on the 2019 Annual Determination (AD), pursuant to its authority under the Endangered Species Act. Through the AD, NOAA Fisheries identifies U.S. fisheries operating in the Atlantic Ocean,
Published
Final Annual Determination for 2018
NOAA Fisheries publishes its final Annual Determination for 2018, pursuant to its authority under the Endangered Species Act. Through the Annual Determination, NOAA Fisheries identifies U.S. fisheries operating in the Atlantic Ocean, Gulf of Mexico, and
Effective
Sea Turtle Conservation; Shrimp Trawling Requirements
On December 16, 2016, NOAA Fisheries published a proposed rule to require TEDs on skimmer trawl, pusher-head trawl, and wing net vessels.
We are proposing to withdraw the alternative tow time restriction and require all skimmer trawls, pusher-head
Effective
Alignment of Atlantic Sea Scallop Turtle Deflector Dredge and Chain Mat Regulated Areas
NOAA Fisheries approves and implements through regulations the measures included in Framework Adjustment 26 to the Atlantic Sea Scallop Fishery Management Plan, which the New England Fishery Management Council adopted and submitted to NOAA Fisheries
Effective
Science
NOAA Fisheries conducts various research activities on the biology, behavior, and ecology of the loggerhead sea turtle. The results of this research are used to inform management decisions and enhance recovery efforts for endangered and threatened loggerhead populations.
Pacific Islands TurtleWatch
TurtleWatch is a mapping project that provides up-to-date information about the thermal habitat of loggerhead sea turtles in the Pacific Ocean north of the Hawaiian Islands. By identifying the ocean habitat favored by loggerhead turtles, the TurtleWatch maps are expected to help longline fishing vessels deploy their fishing gear in areas where loggerheads are less likely to occur. In this way, NOAA Fisheries hopes to provide benefits not only to the turtles, but also to fishermen, who operate under strict limits on the number of turtle interactions allowed.
Population Assessments
Turtle population assessments ideally include information on the species’ abundance and distribution, life history, and human impacts. This information can help us evaluate the effectiveness of conservation and recovery measures, and can help guide actions to enhance recovery. To estimate population abundance, researchers conduct aerial and vessel-based surveys of selected areas and capture and mark turtles in the water and on beaches. We also incorporate data collected on nesting beaches, via stranding networks, and from fisheries observer programs. Other information that informs sea turtle population assessments includes population structure (genetic analyses), age to maturity, survivorship of the various life stages (e.g., hatchling, juvenile, adult), foraging and reproductive behavior, movement and distribution, and habitat studies.
Satellite Tagging and Tracking Studies
Satellite telemetry allows researchers to track sea turtles as they swim from place to place. These satellite tags are designed and attached in a manner that minimizes disturbance to the turtle. The tags will eventually fall off. The data help us understand migration patterns, identify feeding areas, and identify where turtles overlap with their primary threats (e.g., fishing gear).
Research to Reduce Bycatch in Fishing Gear
We observe fisheries to understand the amount of sea turtle bycatch in various fisheries and the ways in which leatherbacks interact with fishing gear. We develop, evaluate, and modify fishing gear and/or fishing practices to reduce sea turtle bycatch while at the same time retaining a sustainable fish catch. These efforts include TED development for trawl fisheries, use of circle hooks and certain bait types in longline fisheries, time and area closures for gillnets, and modifications to pound net leaders.
Learn more about our fishing gear research
Sea Turtle Genetics
NOAA Fisheries’ National Sea Turtle Molecular Genetics Center serves as a worldwide central depository for sea turtle tissue and DNA samples and constitutes a major area of research supporting sea turtle conservation. For example, a turtle’s unique genetic “fingerprint” can be used to determine its nesting population and home nesting beach.
Learn more about our turtle genetics and isotope studies
Life History Studies
Life history studies include gathering information on such things as migration patterns, where turtles nest and forage, growth rates, age to maturity, and sex ratios. This information is important in understanding key biological parameters that influence population trends and inform conservation status.