Abstract
BackgroundMany deep-sea benthic animals occur in patchy distributions separated by thousands of kilometres, yet because deep-sea habitats are remote, little is known about their larval dispersal. Our novel method simulates dispersal by combining data from the Argo array of autonomous oceanographic probes, deep-sea ecological surveys, and comparative invertebrate physiology. The predicted particle tracks allow quantitative, testable predictions about the dispersal of benthic invertebrate larvae in the south-west Pacific.Principal FindingsIn a test case presented here, using non-feeding, non-swimming (lecithotrophic trochophore) larvae of polyplacophoran molluscs (chitons), we show that the likely dispersal pathways in a single generation are significantly shorter than the distances between the three known population centres in our study region. The large-scale density of chiton populations throughout our study region is potentially much greater than present survey data suggest, with intermediate ‘stepping stone’ populations yet to be discovered.Conclusions/SignificanceWe present a new method that is broadly applicable to studies of the dispersal of deep-sea organisms. This test case demonstrates the power and potential applications of our new method, in generating quantitative, testable hypotheses at multiple levels to solve the mismatch between observed and expected distributions: probabilistic predictions of locations of intermediate populations, potential alternative dispersal mechanisms, and expected population genetic structure. The global Argo data have never previously been used to address benthic biology, and our method can be applied to any non-swimming larvae of the deep-sea, giving information upon dispersal corridors and population densities in habitats that remain intrinsically difficult to assess.
Highlights
The habitat connectivity, spatial diversity, and distribution of deep-sea benthic animals are largely determined by the dispersal capacity of their pelagic larvae [1]
We combined records from the work of two previous studies (Table 1; the bounding boxes of these locations are shown in Supporting Information S1)
All of the taxa examined are in the order Lepidopleurida, which is represented in shallow water most commonly by the genus Leptochiton
Summary
The habitat connectivity, spatial diversity, and distribution of deep-sea benthic animals are largely determined by the dispersal capacity of their pelagic larvae [1]. A major challenge in studying these marine animals is the availability of data, because the deep benthic environment is remote and largely unexplored in comparison to its total scale [2,3]. Faced with sparse data on deep-sea dispersal ecology, modelling approaches, such as larval transport models [8], offer the possibility of combining diverse data sets to make novel, testable predictions. The majority of quantitative work on larval transport models to date has focussed on shallow-water organisms and coastal currents [9,10]. There are two substantial factors that differentiate deep-sea dispersal from shallow water models: basin scale current dynamics and local temperature. The predicted particle tracks allow quantitative, testable predictions about the dispersal of benthic invertebrate larvae in the south-west Pacific
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
