Geographic differences in vertical connectivity in the Caribbean coral Montastraea cavernosa despite high levels of horizontal connectivity at shallow depths. Issue 17 (12th August 2014)

• Record Type: Journal Article
• Authors: Serrano, X.; Baums, I. B.; O'Reilly, K.; Smith, T. B.; Jones, R. J.; Shearer, T. L.; Nunes, F. L. D.; Baker, A. C.
• Is Part Of: Molecular ecology. Volume 23:Issue 17(2014)
• Page Start: 4226
• Page End: 4240
• Publication Date: 2014-08-12
• Subjects: Molecular ecology -- Periodicals; Molecular population biology -- Periodicals; 576
• DOI: 10.1111/mec.12861
• Languages: English
• ISSNs: 0962-1083

Abstract

<abstract abstract-type="main" id="mec12861-abs-0001"> <title>Abstract</title> <p>The deep reef refugia hypothesis proposes that deep reefs can act as local recruitment sources for shallow reefs following disturbance. To test this hypothesis, nine polymorphic DNA microsatellite loci were developed and used to assess vertical connectivity in 583 coral colonies of the Caribbean depth‐generalist coral <italic>Montastraea cavernosa</italic>. Samples were collected from three depth zones (≤10, 15–20 and ≥25 m) at sites in Florida (within the Upper Keys, Lower Keys and Dry Tortugas), Bermuda, and the U.S. Virgin Islands. Migration rates were estimated to determine the probability of coral larval migration from shallow to deep and from deep to shallow. Finally, algal symbiont (<italic>Symbiodinium</italic> spp.) diversity and distribution were assessed in a subset of corals to test whether symbiont depth zonation might indicate limited vertical connectivity. Overall, analyses revealed significant genetic differentiation by depth in Florida, but not in Bermuda or the U.S. Virgin Islands, despite high levels of horizontal connectivity between these geographic locations at shallow depths. Within Florida, greater vertical connectivity was observed in the Dry Tortugas compared to the Lower or Upper Keys. However, at all sites, and regardless of the extent of vertical connectivity, migration occurred asymmetrically, with greater likelihood of migration from shallow to intermediate/deep habitats. Finally, most colonies hosted a single <italic>Symbiodinium</italic> type (C3), ruling out symbiont depth zonation of the dominant symbiont type as a structuring factor. Together, these findings suggest that the potential for shallow reefs to recover from deep‐water refugia in <italic>M. cavernosa</italic> is location‐specific, varying among and within geographic locations likely as a consequence of local hydrology.</p> </abstract>