Genetic and migratory evidence for sympatric spawning of tropical Pacific eels from Vanuatu

Abstract

Ti t l e G e n e tic a n d m i g r a t o ry e vi d e n c e fo r sy m p a t ri c s p a w ni n g of t r o pi c al p a cific e el s fro m Van u a t u

The ecology of oceanic dispersal and survival of anguillid leptocephali

“…These surveys expanded out across the Indo-Pacific (Aoyama et al 2003(Aoyama et al , 2007Kuroki et al 2006) with evidence of offshore spawning by eels in the western South Pacific being found (Kuroki et al 2008;Aoyama 2009) and local spawning by eels in the Indonesian seas being discovered (Aoyama et al 2003). These collections and genetic or morphological information about anguillid population structures (Minegishi et al 2008;Watanabe et al 2008Watanabe et al , 2011 and silver eel tagging studies (Schabetsberger et al 2015;Jellyman and Tsukamoto 2010) led to ideas about the locations of Indo-Pacific anguillid spawning areas ( Fig. 1A), but there is still a lack of information about many species.…”

“…The sizes of these larvae indicate that there are spawning areas in the region northeast of New Caledonia and north of Fiji. Information from silver eel tagging studies also point to a spawning area of A. marmorata and Anguilla megastoma in the region (Schabetsberger et al 2015) and that A. dieffenbachii from New Zealand may spawn east of New Caledonia (Jellyman and Tsukamoto 2010). The westward flow of the South Equatorial Current would take leptocephali to regions along the margin of the western South Pacific and then the East Australian Current would take them southward along Australia where some recruit as glass eels (Shiao et al 2002).…”

“…Anguillids in the western South Pacific, such as the two subspecies of Anguilla australis from Australia and New Zealand, the New Zealand longfin eel (Anguilla dieffenbachii) and the Australian longfin eel (Anguilla reinhartii), migrate far offshore to spawn in the South Equatorial Current according to collections of their larvae (Jellyman 2003;Kuroki et al 2008;Aoyama 2009) or data from satellite pop-up tagging studies of migrating silver eels (Jellyman and Tsukamoto 2010). There is also evidence about the location of a separate tropical eel spawning area in the western South Pacific from tagging studies (Schabetsberger et al 2015), and larval collections have indicated there is an anguillid spawning area in the eastern Indian Ocean (Jespersen 1942;Aoyama et al 2007). The spawning areas that are known or inferred are located in westward flowing currents that transport the larvae towards boundary currents or are closer to landmasses or islands (Fig.…”

Spatial ecology of blue shark and shortfin mako in southern Peru: local abundance, habitat preferences and implications for conservation

“…Lunar illumination and lunar phase affect fish species in multiple manners, including visual detection of prey and predator camouflage, and may change fish distribution, thermal exposure, and activity patterns (Metcalfe et al 1997, Hanson et al 2008, Aarestrup et al 2009, Afonso & Hazin 2015, Papastamatiou et al 2015, Schabetsberger et al 2015. Shark prey species may modify vertical distributions according to the lunar phase (Schabetsberger et al 2013(Schabetsberger et al , 2015, suggesting that lunar phase (and illumination) influences the distribution of foraging sharks.…”

“…Shark prey species may modify vertical distributions according to the lunar phase (Schabetsberger et al 2013(Schabetsberger et al , 2015, suggesting that lunar phase (and illumination) influences the distribution of foraging sharks. Because lunar effects on pelagic sharks are unknown in the Southeast Pacific, the effects of lunar illumination were tested on P. glauca and I. oxyrinchus CPUE.…”