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Essay / Loggerhead Sea Turtle Essay - 714
The loggerhead sea turtle, Caretta caretta, is an endangered species with highly migratory behavior and changing habitat requirements depending on maturity (NMFS and USFWS 1998). Loggerhead sea turtle nesting areas are generally found in warm temperate regions (NMFS and USFWS 1998). In the original USFWS listing (1978), the loggerhead sea turtle was considered threatened throughout its range. The document goes on to state that one of the main threats to the loggerhead sea turtle was that it was captured for its shell or as food; eggs were considered a sought-after food and source of protein. Regulations have been put in place to protect the loggerhead sea turtle, such as banning foreign trade, import and export (USFWS, 1978). One factor considered a past threat was the inadequacy of existing regulations regarding the loggerhead sea turtle (USFWS, 1978). Since the loggerhead sea turtle was listed, numerous regulations and recovery plans have been developed. However, many of the threats described in the 1978 loggerhead turtle listing are still present threats today. These threats include human expansion reducing nesting habitat through beach development, including the construction of artificial lights and sea walls, disease, and predation of hatchlings (USFWS, 1978). Today, the current status of the loggerhead sea turtle remains unchanged and it remains listed as a threatened species (NMFS and USFWS 2007). This was determined in the most recent 5-year review using molecular markers to help define population genetic structure (NMFS and USFWS 2007). One of the highest priority threats to the loggerhead sea turtle is bycatch (Figure 1). Loggerhead turtles are often captured in Large Paper Areas (SQE) based on the Near Extinction Threshold (QET) for the Northwest Atlantic Ocean DPS. The QET is defined as the proportion of the current abundance of females. The dotted lines indicate SQE = 0.3, which was adapted as a threshold for the analysis. NRU = Northern Recovery Unit, PFRU = Peninsular Florida Recovery Unit, NGMRU = Northern Gulf of Mexico Recovery Unit and GCRU = Greater Caribbean Recovery Unit. According to Conant et al. 2009.Figure 3. Changes in the number of nesting females on nesting beaches for the Northwest Atlantic Ocean DPS. The number of nesting females was calculated from the number of nests observed divided by the average clutch frequency (5 years-1; Table 1). NRU = Northern Recovery Unit, PFRU = Peninsular Florida Recovery Unit, NGMRU = Northern Gulf of Mexico Recovery Unit and GCRU = Greater Caribbean Recovery Unit. According to Conant et al.. 2009.