Artificial lighting can cause disorientation or misorientation ot both adults and hatchlings. 

 Loggerhead turtle hatchlings are attracted to artificial light, which disrupts their natural sea- 

 finding behavior and can result in increased predation and mortality. In addition, adult females 

 are discouraged from nesting in highly developed areas with intense artificial lighting. 



Erosion of nesting beaches can result in loss of nesting habitat and incubating nests. However, 

 natural processes of beach erosion are not generally a significant tlireat. 



Beach armoring (seawalls, revetments, riprap, sandbags and sand fences) to protect property 

 from erosion can cause the loss of dr\' nesting beach and/or interference with access to suitable 

 nesting sites. 



Beach nourishment results in heavy machinerv'. pipelines, increased human activity and artificial 

 lighting on a project beach, and can cause the burial of nests and disturbance of nesting turtles. 



Repeated mechanical raking of nesting beaches by heavy machinery can result in compacting 

 sand and cause tire ruts which may hinder or trap hatchlings. Rakes can penetrate the surface 

 and disturb or uncover a nest. Disposing of the raked debris on the high beach can cover nests 

 and may alter nest temperature affecting temperature dependent sex determination mechanisms. 



Human disturbance of nesting females is a serious concern. Also, heavy utilization of nesting 

 beaches by humans may result in lowered hatchling success due to sand compaction. 



The placement of physical obstacles on a beach can hamper or deter nesting attempts as well as 

 interfere with the incubation of eggs and the emergence of hatchlings. 



The use of off-road vehicles on beaches is a serious problem in certain areas. It may result in 

 decreased hatchling success due to sand compaction, or directly kill hatchlings and adults. Tire 

 ruts may also interfere with the ability of hatchlings to get to the ocean. 



The invasion of nesting sites by non-native beach vegetation can lead to increased erosion and 

 degradation of nesting habitat. Trees shading a beach can also change nest temperatures, altering 

 the natural sex ratio of the hatchlings. 



Impacts in the marine environment 



Commercial fishing: It is estimated that before the implementation of turtle excluder devices 

 (TEDs). the U.S. commercial shrimp fleet killed between 5,000 and 50,000 loggerheads each 

 year. TED regulations have been in place in the U.S. and in Mexico for several years, however, 

 shrimp trawling still poses a threat. Although, recent data indicates that since the implementation 

 of TED requirements lethal takes of loggerheads have been reduced by approximately 54%. 

 Mid-water and other bottom trawl fishing gear are also serious threats. Turtles are taken by purse 

 seine fisheries in the Atlantic and Gulf of Mexico, but the magnitude of take is currently not 

 known. Several thousand commercial vessels and an extensive recreational fishery are involved 

 in hook and line fishing for various coastal species. The capture of turtles in this fisherv' is 

 common, but the number is not known. 



Significant numbers of loggerhead turtles were killed by gill and trammel net fisheries off the 

 eastern coast of central Florida. However, in 1995, gill and trammel net fisheries were banned 

 from operating in Florida state waters. Pound net fisheries are primarily a problem in waters off 

 Virginia and North Carolina, where turtles become entangled in the gear and drown. Loggerhead 



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