Chelonian Conserv Biol 5:262–268īowen BW, Karl SA (2007) Population genetics and phylogeny of sea turtles. Ecol Appl 10:269–282ījorndal KA, Bolten AB, Moreira L, Bellini C, Marcovaldi MA (2006) Population structure and diversity of Brazilian green turtle rookeries based on mitochondrial DNA sequences. Mar Turt Newsl 100:16–21ījorndal KA, Bolten AB, Chaloupka M (2000) Green turtle somatic growth model: evidence for density dependence. J Mar Biol Assoc UK 93:1117–1132ījorndal KA, Bolten AB (2003) From ghosts to key species: restoring sea turtles to fulfil their ecological roles. Mar Biol 145:1043–1059īellini C, Santos AJB, Grossman A, Marcovaldi MA, Barata PCR (2013) Green turtle ( Chelonia mydas) nesting on Atol das Rocas, north-eastern Brazil, 1990–2008. Biol Conserv 117:491–498īalazs GH, Chaloupka M (2004b) Spatial and temporal variability in somatic growth of green sea turtles ( Chelonia mydas) resident in the Hawaiian Archipelago. Endang Species Res 14:193–201īalazs GH, Chaloupka M (2004a) Thirty-year recovery trend in the once depleted Hawaiian green sea turtle stock. While not a cause for complacency, these trends are encouraging and demonstrate the capacity of marine megafauna to rebound when anthropogenic pressures are alleviated through conservation action.Īlmeida AP, Moreira LMP, Bruno SC, Thomé JCA, Martins AS, Bolten AB, Bjorndal KA (2011) Green turtle nesting on Trindade Island, Brazil: abundance, trends and biometrics. Overall, the Ascension Island green turtle population appears to be recovering strongly, mirroring positive trends for this species across many parts of its geographic range. More rapid population growth close to human centres seems counterintuitive, but may reflect the more intensive depletion of these accessible, local stocks during the harvesting era. More than 97 % of this variation could be explained by distance from the main human settlement of Georgetown-the historic centre of turtle harvesting-with beaches closer to Georgetown experiencing the most rapid growth. Interestingly, however, rates of increase in nesting activity have varied dramatically among nesting beaches, ranging from 0.4 to 6 % growth per annum. Since monitoring began in 1977, the average number of green turtle clutches deposited annually at Ascension Island has increased sixfold, from approximately 3,700 to 23,700 a trend that has been accompanied by a significant decrease in the average size of nesting females. Using a monitoring dataset spanning 36 years, we modelled long-term trends in nesting activity at both a rookery level and across individual nesting beaches and beach clusters. In this study, we report on the status of the South Atlantic’s largest green turtle ( Chelonia mydas) nesting aggregation at Ascension Island, 70 years after legal protection and the cessation of commercial turtle harvesting that decimated the population. Although many species of marine mega-vertebrates are threatened as a result of human activity, some populations are showing promising signs of recovery following decades of protection.
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