Active positioning of vent larvae at a mid-ocean ridge
Mullineaux, Lauren S.
McGillicuddy, Dennis J.
Mills, Susan W.
Kosnyrev, V. K.
Thurnherr, Andreas M.
Ledwell, James R.
Lavelle, J. William
MetadataShow full item record
The vertical position of larvae of vent species above a mid-ocean ridge potentially has a strong effect on their dispersal. Larvae may be advected upward in the buoyant vent plume, or move as a consequence of their buoyancy or active swimming. Alternatively, they may be retained near bottom by the topography of the axial trough, or by downward swimming. At vents near 9°50’N on the axis of the East Pacific Rise, evidence for active larval positioning was detected in a comparison between field observations of larvae in the plankton in 2006 and 2007 and distributions of non-swimming larvae in a two-dimensional bio-physical model. In the field, few vent larvae were collected at the level of the neutrally buoyant plume (~75 m above bottom); their relative abundances at that height were much lower than those of simulated larvae from a near-bottom release in the model. This discrepancy was observed for many vent species, particularly gastropods, suggesting that they may actively remain near bottom by sinking or swimming downward. Near the seafloor, larval abundance decreased from the ridge axis to 1000 m off axis much more strongly in the observations than in the simulations, again pointing to behavior as a potential regulator of larval transport. We suspect that transport off axis was reduced by downward-moving behavior, which positioned larvae into locations where they were isolated from cross-ridge currents by seafloor topography, such as the walls of the axial valley – which are not resolved in the model. Cross-ridge gradients in larval abundance varied between gastropods and polychaetes, indicating that behavior may vary between taxonomic groups, and possibly between species. These results suggest that behaviorally mediated retention of vent larvae may be common, even for species that have a long planktonic larval duration and are capable of long-distance dispersal.
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 92 (2013): 46-57, doi:10.1016/j.dsr2.2013.03.032.
Showing items related by title, author, creator and subject.
Advanced geophysical studies of accretion of oceanic lithosphere in Mid-Ocean Ridges characterized by contrasting tectono-magmatic settings Xu, Min (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2012-02)The structure of the oceanic lithosphere results from magmatic and extensional processes taking place at mid-ocean ridges (MORs). The temporal and spatial scales of the variability of these two processes control the ...
Effects of variable magma supply on mid-ocean ridge eruptions : constraints from mapped lava flow fields along the Galápagos Spreading Center Colman, Alice; Sinton, John M.; White, Scott M.; McClinton, J. Timothy; Bowles, Julie A.; Rubin, Kenneth H.; Behn, Mark D.; Cushman, Buffy; Eason, Deborah E.; Gregg, Tracy K. P.; Gronvold, Karl; Hidalgo, Silvana; Howell, Julia; Neill, Owen; Russo, Chris (American Geophysical Union, 2012-08-25)Mapping and sampling of 18 eruptive units in two study areas along the Galápagos Spreading Center (GSC) provide insight into how magma supply affects mid-ocean ridge (MOR) volcanic eruptions. The two study areas have similar ...
Examining the effects of mid ocean ridge topography on 3D marine magnetometric resistivity model responses Lassner, Lisa A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2004-06)Methods which measure seafloor resistivity are uniquely suited to studying hydrothermal circulation in the crust. The magnetometric resistivity (MMR) technique is a galvanic method which uses a bipole current source with ...