Restoration Potential: Because so little is known loggerhead population dynamics and demography, it is difficult to assess restoration potential. However, most authors, in discussing conservation strategies, seem optimistic about the loggerhead's recovery if the ongoing population declines can be halted. Turtle excluder devices (TEDs) appear to be effective in reducing mortality associated with the shrimp fishery, improving the outlook for population recovery (Crowder et al. 1995)
Preserve Selection and Design Considerations: It is impossible to protect the loggerhead throughout its life cycle due to its expansive range and wandering years at sea. However, nesting beaches can and should be protected. These beaches should be undeveloped, unlighted, virtually unused by humans, and fishing, especially shrimp trawling, should not be allowed near them, especially in the breeding season. These beaches should be carefully managed for the benefit of the loggerhead.
Management Requirements: Worldwide public awareness of plight of sea turtles needs to be improved. Frazer (1992) emphasized the primary need for clean and productive marine and coastal environments; installation of turtle excluder devices in shrimp trawl nets and use of low pressure sodium lighting on beaches were suggested as appropriate sea turtle conservation technologies, whereas headstarting, captive breeding, and hatcheries were regarded as ineffective at best.
The immediate management goal should be to stop the population decline. Although natural mortality contributes to the decline, it is not easy to manipulate. Efforts should be focused on protecting nesting habitat, nesting females, and nests, and on lowering mortality caused by humans. Specific beneficial management activities related to nesting include relocating nests threatened by erosion, restricting beach armoring, closely monitoring beach nourishment, enforcing lighting ordinances, regulating off road vehicles, and protecting nests from pedestrian traffic and beach cleaning equipment by either moving eggs to safer places or marking their presence. Disturbance of nesting females and harvest of adults and eggs should be prevented.
Lights near beaches may disorient hatchlings (Peters and Verhoeven 1994) and discourage nesting; beach lighting restrictions on nesting baches should include the entire period of darkness (Witherington et al. 1990). If lighting cannot be eliminated, low pressure sodium vapor lights may be the least disruptive to nesting turtles (Witherington 1992). Adding a low light barrier (simulating a dune or dense vegetation) improved hatchling orientation accuracy on urban beach segments exposed to lights in Florida (Salmon et al. 1995).
In addition to protection and suitable management of nesting habitat, reduction in trawl-related mortality (associated with shrimping), through the use of turtle excluder devices (TEDs, required for offshore shrimpers as of July 1989), seasonal fisheries closures, and reduced tow times, are regarded as primary management needs (CSTC 1990, USFWS 1990, Crowder et al. 1994, Lewison et al. 2003). Use of TEDs by shrimp trawlers theoretically could reduce the capture of sea turtles to 3% of the rate without the TED.
TEDs are designed to be installed in shrimp-trawl gear with the purpose of releasing sea turtles and other large objects from nets without releasing shrimp. By November of 1989, six TEDs had been approved by the National Marine Fisheries Service (NMFS), meaning that they are able to exclude at least 97% of the sea turtles otherwise captured and retained in a control trawl without a TED. Use of TEDs should be mandated and regulated from Cape Hatteras to the Texas-Mexican border, as well as all other areas where sea turtles are known to be caught in shrimp trawls. Tow-time limits can reduce the average rate of mortality of sea turtles to a negligible point as tow time is reduced to 60 minutes or less. This can be better than TEDs for areas with a lot of debris. The recommended tow-times are vary seasonally, specifying 40 minutes in the summer and 60 minutes in the winter. Limited time/area closures for turtle "hot spots" should be considered. See NMFS (1993) for recent shrimp trawling regulations for an area off the coast of North Carolina (allow tow-time limits as an interim alternative to the use of turtle excluder devices). See NMFS (Federal Register, 19 December 1996, pp. 66933-66947) for recent amendments to regulations pertaining to the use of turtle excluder devices along the Gulf and Atlantic coasts of the southeastern U.S. Population models indicate that good compliance with regulations requiring TEDs year-round in all waters of the southeastern United States could allow the population to increase much faster than expected under the "seasonal offshore" regulations (Crowder et al. 1994).
Efforts should be made to avoid sea turtle entrainment in power plant water intakes. Additionally, the use of explosives to remove oil rigs should be prohibited until more is known about its affect on loggerheads.
Effort is needed in informing and educating the public on minimizing disturbance to nesting turtles, protecting nests, and rescuing disorientated hatchlings. Mitchell (1991) noted the importance of public education in reducing mortality caused by humans.
In some areas, predator control may be needed to combat raccoons and other predators whose coastal populations are abnormally high due to food resources being augmented by human refuse. Wire-mesh predator (e.g., raccoon) exclosures around nests have been used in some areas (e.g., Canaveral National Seashore) to enhance reproductive success (1994 End. Sp. Tech. Bull. 19(2):16). However, in Florida, Mroziak et al. (2000) found that predator exclosure cages failed to protect nests and may have attracted them; the authors concluded that reducing predator populations is more effective than using cages to protect nests. See Matthews and Moseley (1990) for examples of interagency cooperation in protecting nesting areas and reducing egg loss to predators. Elimination/control of feral livestock on barrier islands may allow increased production of hatchlings (Shoop et al. 1985).
Public purchase of undeveloped beaches may be effective in providing prolonged protection of turtles and their habitat. Available lands should be protected before they are lost to development interests. In Florida, 16 km of undeveloped beach from Melbourne Beach to Wabasso Beach is available and should be protected as this is a tremendously important nesting area from a global perspective. Also, the establishment of a marine park at Rancho Nuevo in Mexico would be beneficial.
Headstarting and captive breeding should remain research tools but should not be used as substitutes for other conservation measures. Eggs relocated to polystyrene incubators have higher hatching success than do eggs in undisturbed nests or eggs relocated to other beach sites (Wyneken et al. 1988). See McGehee (1990) for information on egg incubation procedures. See Mrosovsky and Benabib (1990) for an evaluation of methods for sexing hatchlings.
See Dodd (1992) for protection recommendations for Florida.
See recovery plan: Marine Turtle Recovery Team (1984). See also "Recovery plan for U.S. Pacific populations of the loggerhead turtle (Caretta caretta)" (NMFS 1998). See USFWS (1998) for detailed information on management and recovery, especially for populations in Florida.
See Dodd (1988) for further discussion of management strategies.
Management Programs: One program consists of a joint state, federal, and private effort to provide permanent protection for 15 km of 34 km of high-density sea turtle nesting habitat between Melbourne and Wabasso beaches on the Atlantic coast of east-central Florida.
State and federal agencies are involved in regulating projects which relocate nests to higher sites on a dune or into a hatchery to combat erosion.
The NMFS Southeast Regional Office has begun many programs on behalf of the loggerhead. These include regulation development, recovery planning and implementation, information dissemination, TED certification, and permit administration. NMFS also regulates beach nourishment programs.
Many states, counties, and towns are making progress in mitigating the deleterious effects of light on nesting females and hatchlings.
The Center for Marine Conservation, Florida Power and Light Co., NMFS, FWS, and environmental groups together have put out a wide variety of material in an effort to educate the public on sea turtle conservation needs.
MARPOL and other programs to reduce marine pollution are in place and recently have been strengthened.
The Wider Carribbean Sea Turtle Conservation Network (WIDECAST) is a United Nations-sponsored program devoted to the recovery of endangered Caribbean sea turtles.
Management Research Programs: One management research program is referred to as headstarting, a procedure in which hatchlings are retained in captivity and reared for at least several months with the goal of increasing the juvenile population by reducing hatchling mortality. The effectiveness of this technique is strongly debated. Survivors of such turtles in the wild is documented, but no nesters have ever been found. The practice has been very valuable in increasing the understanding about elements of physiology and behavior of sea turtles. In 1989, Florida terminated its 30-year-old green turtle and loggerhead headstart program because of problems such as skewed sex ratios from artificial incubation, possible interference with imprinting, nutritional deficiencies of hatchlings due to confinement, and possible behavioral modifications. Additionally, the practice is expensive.
Loggerheads have been successfully reared in captivity from egg to adulthood, and the adults have laid fertile eggs. The ability of such captive-bred turtles to survive and reproduce in the wild, however, is not known.
Some experimentation with artificial imprinting has been conducted. It is thought that olfactory imprinting on the natal beach may occur on hatchlings. Perhaps the imprinting cues can be altered to a new beach by relocating the eggs, thereby facilitating the creation of new nesting sites and restoration of old ones.
The Sea Turtle Dredging Task Force, including representatives of the Army Corps of Engineers, the NMFS, the USFWS, the Florida DNR, and the Navy, was created in 1981. They have instituted many different research programs such as an observer program with an on-board biologist to document the take of sea turtles by dredges. Screens have been installed on dredge discharge ports to monitor the presence of sea turtle parts. The task force is involved in an investigation of the configuration and relative threat to sea turtles of various types of dredges and dredge dragheads. Also under investigation are various methods designed to repel turtles from the channel to be dredged or from the vicinity of the dredge. Some turtles are being radio-tracked in navigation channels. Another task force effort is to determine the frequency and distribution of sea turtles in key navigation channels of Florida's coast and elsewhere.
Research is being performed on the use of low pressure sodium lights on nesting beaches. They seem to have a minimal effect on hatchling orientation, however, they still prompt some concerns.
Management Research Needs: An enlargement of tagging programs and the creation of new ones, paying special attention to the problem of tag loss, will help in gaining much-needed population data. The ecology and movements of hatchlings and young need to be investigated.
Research on the effects and prevalence of cold stunning should be carried out. Improved resuscitation techniques of comatose turtles should be developed.
Accurate postmortem techniques need to be developed to determine the role of plastic ingestion on turtle deaths, and documentation is needed of the extent of the problem. Also, information is needed on the effects of petroleum ingestion and fouling.
Detailed examination of the potential of shrimping in fishing zones and times of the year when damage to turtle populations would be minimal without TED or tow- time restrictions is needed. Improved TEDs should be developed and new alternatives explored. The effectiveness of tow-time limitations needs to be documented. More information is needed on the impact of groundfish trawling, set-net and long-line fishing, gill nets, and pound-net fishing.
The complex effects of artificial protection of early life stages of sea turtles needs to be determined.