Details

Autor(en) / Beteiligte

• Gaos, Alexander R.
• Lewison, Rebecca L.
• Liles, Michael J.
• Gadea, Velkiss
• Altamirano, Eduardo
• Henríquez, Ana V.
• Torres, Perla
• Urteaga, José
• Vallejo, Felipe
• Baquero, Andres
• LeMarie, Carolina
• Muñoz, Juan Pablo
• Chaves, Jaime A.
• Hart, Catherine E.
• Peña de Niz, Alejandro
• Chácon, Didiher
• Fonseca, Luis
• Otterstrom, Sarah
• Yañez, Ingrid L.
• LaCasella, Erin L.
• Frey, Amy
• Jensen, Michael P.
• Dutton, Peter H.

Titel

Hawksbill turtle terra incognita: conservation genetics of eastern Pacific rookeries

Ist Teil von

• Ecology and evolution, 2016-02, Vol.6 (4), p.1251-1264

Ort / Verlag

England: John Wiley & Sons, Inc

Erscheinungsjahr

2016

Link zum Volltext

Quelle

Wiley Online Library Journals

Beschreibungen/Notizen

• Prior to 2008 and the discovery of several important hawksbill turtle (Eretmochelys imbricata) nesting colonies in the EP (Eastern Pacific), the species was considered virtually absent from the region. Research since that time has yielded new insights into EP hawksbills, salient among them being the use of mangrove estuaries for nesting. These recent revelations have raised interest in the genetic characterization of hawksbills in the EP, studies of which have remained lacking to date. Between 2008 and 2014, we collected tissue samples from 269 nesting hawksbills at nine rookeries across the EP and used mitochondrial DNA sequences (766 bp) to generate the first genetic characterization of rookeries in the region. Our results inform genetic diversity, population differentiation, and phylogeography of the species. Hawksbills in the EP demonstrate low genetic diversity: We identified a total of only seven haplotypes across the region, including five new and two previously identified nesting haplotypes (pooled frequencies of 58.4% and 41.6%, respectively), the former only evident in Central American rookeries. Despite low genetic diversity, we found strong stock structure between the four principal rookeries, suggesting the existence of multiple populations and warranting their recognition as distinct management units. Furthermore, haplotypes EiIP106 and EiIP108 are unique to hawksbills that nest in mangrove estuaries, a behavior found only in hawksbills along Pacific Central America. The detected genetic differentiation supports the existence of a novel mangrove estuary “reproductive ecotype” that may warrant additional conservation attention. From a phylogeographic perspective, our research indicates hawksbills colonized the EP via the Indo‐Pacific, and do not represent relict populations isolated from the Atlantic by the rising of the Panama Isthmus. Low overall genetic diversity in the EP is likely the combined result of few rookeries, extremely small reproductive populations and evolutionarily recent colonization events. Additional research with larger sample sizes and variable markers will help further genetic understanding of hawksbill turtles in the EP. This study represents the first genetic characterization of critically endangered hawksbill turtle rookeries in the eastern Pacific Ocean. Despite low genetic diversity in the region, we found strong stock structuring among four rookeries. Phylogenetic analysis revealed that hawksbills colonized the eastern Pacific via the Indo‐Pacific, rather than representing a relict population isolated from the Atlantic by the rising of the Panama Isthmus. We found haplotypes unique to hawksbills nesting in mangrove estuaries and this behavior is exclusive to hawksbills along Pacific Central America, indicating the existence of a novel mangrove estuary reproductive ecotype.