title: Genetic structure of the crown-of-thorns seastar in the Pacific Ocean, with focus on Guam.
abstract: Population outbreaks of the corallivorous crown-of-thorns seastar (COTS), Acanthaster 'planci' L., are among the most important biological disturbances of tropical coral reefs. Over the past 50 years, several devastating outbreaks have been documented around Guam, an island in the western Pacific Ocean. Previous analyses have shown that in the Pacific Ocean, COTS larval dispersal may be geographically restricted to certain regions. Here, we assess the genetic structure of Pacific COTS populations and compared samples from around Guam with a number of distant localities in the Pacific Ocean, and focused on determining the degree of genetic structure among populations previously considered to be isolated. Using microsatellites, we document substantial genetic structure between 14 localities from different geographical regions in the Pacific Ocean. Populations from the 14 locations sampled were found to be structured in three significantly differentiated groups: (1) all locations immediately around Guam, as well as Kingman Reef and Swains Island; (2) Japan, Philippines, GBR and Vanuatu; and (3) Johnston Atoll, which was significantly different from all other localities. The lack of genetic differentiation between Guam and extremely distant populations from Kingman Reef and Swains Island suggests potential long-distance dispersal of COTS in the Pacific.
authors.affiliation: Department of Earth and Environmental Sciences, Palaeontology & Geobiology, Ludwig-Maximilians-Universität München , München , Germany.
authors.forename: Sergio
authors.initials: S
authors.lastname: Tusso
authors.affiliation: Department of Anatomy (Neuroanatomy), University of Cologne , Köln , Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Morcinek
authors.affiliation: Environment Department, Pöyry Switzerland Ltd. , Zurich , Switzerland.
authors.forename: Catherine
authors.initials: C
authors.lastname: Vogler
authors.affiliation: Environmental Biochemistry, Carl-von-Ossietzky University Oldenburg, ICBM-Terramare , Wilhelmshaven , Germany.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Schupp
authors.affiliation: ARC Centre of Excellence for Coral Reef Studies, James Cook University , Townsville, Queensland , Australia.
authors.forename: Ciemon F
authors.initials: CF
authors.lastname: Caballes
authors.affiliation: Department of Earth and Environmental Sciences, Palaeontology & Geobiology, Ludwig-Maximilians-Universität München , München , Germany.
authors.forename: Sergio
authors.initials: S
authors.lastname: Vargas
authors.affiliation: Department of Earth and Environmental Sciences, Palaeontology & Geobiology, Ludwig-Maximilians-Universität München, München, Germany; SNSB-Bavarian State Collections of Palaeontology and Geology, München, Germany; GeoBio-Center, Ludwig-Maximilians-Universität München, München, Germany.
authors.forename: Gert
authors.initials: G
authors.lastname: Wörheide
keywords: Acanthaster ‘planci’; COTS; Crown-of-thorns seastar; Genetic structure; Microsatellites; Pacific