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Coral Reefs

, Volume 29, Issue 2, pp 369–377 | Cite as

Mesophotic communities of the insular shelf at Tutuila, American Samoa

  • A. Y. BareEmail author
  • K. L. Grimshaw
  • J. J. RooneyEmail author
  • M. G. Sabater
  • D. Fenner
  • B. Carroll
Report

Abstract

An investigation into the insular shelf and submerged banks surrounding Tutuila, American Samoa, was conducted using a towed camera system. Surveys confirmed the presence of zooxanthellate scleractinian coral communities at mesophotic depths (30–110 m). Quantification of video data, separated into 10-m-depth intervals, yielded a vertical, landward-to-seaward and horizontal distribution of benthic assemblages. Hard substrata composed a majority of bottom cover in shallow water, whereas unconsolidated sediments dominated the deep insular shelf and outer reef slopes. Scleractinian coral cover was highest atop mid-shelf patch reefs and on the submerged bank tops in depths of 30–50 m. Macroalgal cover was highest near shore and on reef slopes approaching the bank tops at 50–60 m. Percent cover of scleractinian coral colony morphology revealed a number of trends. Encrusting corals belonging to the genus Montipora were most abundant at shallow depths with cover gradually decreasing as depth increased. Massive corals, such as Porites spp., displayed a similar trend. Percent cover values of plate-like corals formed a normal distribution, with the highest cover observed in the 60–70 m depth range. Shallow plate-like corals belonged mostly to the genus Acropora and appeared to be significantly prevalent on the northeastern and eastern banks. Deeper plate-like corals on the reef slopes were dominated by Leptoseris, Pachyseris, or Montipora genera. Branching coral cover was high in the 80–110 m depth range. Columnar and free-living corals were also occasionally observed from 40–70 m.

Keywords

Mesophotic coral ecosystem Insular shelf Submerged banks Coral reefs Tutuila American Samoa 

Notes

Acknowledgements

Funding to the NOAA Pacific Islands Fisheries Science Center’s Coral Reef Ecosystem Division for scientific expeditions to American Samoa was provided by the NOAA Coral Reef Conservation Program. We greatly appreciate the field assistance of Emily Hirsch, Frances Lichowski, and Gillian Clague. We also express our gratitude to Kurt Hagedorn and Andy Wearing of the M/V Bonavista II.

References

  1. Armstrong RA, Singh H, Torres J, Nemeth RS, Can A, Roman C, Eustice R, Riggs L, Garcia-Moliner G (2006) Characterizing the deep insular shelf coral reef habitat of the Hind Bank marine conservation district (US Virgin Islands) using the Seabed autonomous underwater vehicle. Cont Shelf Res 26:194–205CrossRefGoogle Scholar
  2. Bak RPM, Nieuwland G, Meesters EH (2005) Coral reef crisis in deep and shallow reefs: 30 years of constancy and change in reefs of Curacao and Bonaire. Coral Reefs 24:475–479CrossRefGoogle Scholar
  3. Birkeland C, Craig P, Fenner D, Smith L, Kiene WE, Riegl B (2008) Geologic setting and ecological functioning of coral reefs in American Samoa. In: Riegl B, Dodge RE (eds) Coral reefs of the USA, v. 1 of Coral reefs of the world. Springer Science +Business Media, Berlin, pp 741–765Google Scholar
  4. Brainard RE, Asher J, Gove J, Helyer J, Kenyon J, Mancini F, Miller J, Myhre S, Nadon M, Rooney J, et al. (2008) Coral reef ecosystem monitoring report for American Samoa: 2002-2006. NOAA Fisheries Pacific Islands Fisheries Science Center, PIFSC Special Publication SP-08-002, p 472 +AppGoogle Scholar
  5. Fenner D, Speicher M, Gulick S, Abey G, Aletto SC, Anderson P, Carroll B, DiDonato E, DiDonato G, Farmer V (2008) The state of coral reef ecosystems of American Samoa. In: Waddell JE, Clarke AM et al (eds) The state of coral reef ecosystems of the United States and the Pacific Freely Associated States: 2008. NOAA Tech. Memorandum NOS NCCOS 73. NOAA NCCOS Center for Coastal Monitoring and Assessment’s Biogeography Team, Silver Spring, MD, pp 307–351Google Scholar
  6. Fricke H, Meischner D (1985) Depth limits of Bermudan scleractinian corals: a submersible survey. Mar Biol 88:175–187CrossRefGoogle Scholar
  7. Glynn PW (1996) Coral reef bleaching: facts, hypotheses and implications. Global Change Biol 2:495–509CrossRefGoogle Scholar
  8. Green AL, Birkeland CE, Randall RH (1999) Twenty years of disturbance and change in Fagatele Bay National Marine Sanctuary, American Samoa. Pac Sci 53:376–400Google Scholar
  9. Hinderstein LM, Marr JCA, Martinez FA, Dowgiallo MJ, Puglise KA, Pyle RL, Zawada DG, Appeldorn R (2010) Introduction to mesophotic coral ecosystems: Characterization, ecology, and management. Coral Reefs 29: this issueGoogle Scholar
  10. Jarrett BD, Hine AC, Halley RB, Naar DF, Locker SD, Neumann AC, Twichell D, Hu C, Donahue BT, Jaap WC, Palandro D, Ciembronowicz K (2005) Strange bedfellows—a deep hermatypic coral reef superimposed on a drowned barrier island; southern Pulley Ridge, SW Florida platform margin. Mar Geol 214:295–307CrossRefGoogle Scholar
  11. Kahng SE, Kelley CD (2007) Vertical zonation of the megabenthic taxa on a deep photosynthetic reef (50–140 m) in the Au’au Channel, Hawaii. Coral Reefs 26:679–687CrossRefGoogle Scholar
  12. Kahng SE, Maragos JE (2006) The deepest, zooxanthellate scleractinian corals in the world? Coral Reefs 25:254CrossRefGoogle Scholar
  13. Lang JC (1974) Biological zonation at the base of a reef. Am Sci 62:272–281Google Scholar
  14. Lesser PL, Slattery M, Leichter JJ (2009) Ecology of mesophotic coral reefs. J Exp Mar Biol Ecol 375:1–8CrossRefGoogle Scholar
  15. Menza C, Kendall M, Rogers C, Miller J (2007) A deep reef in deep trouble. Cont Shelf Res 27:2224–2230CrossRefGoogle Scholar
  16. Menza C, Kendall M, Hile S (2008) The deeper we go the less we know. Rev Biol Trop 56:11–24Google Scholar
  17. Pyle R (2001) B.P. Bishop Museum exploration and discovery: the coral-reef twilight zone, Fagatele Bay National Marine Sanctuary, 14–18 May 2001. Bernice Pauahi Bishop Museum. http://www2.bishopmuseum.org/PBS/samoatz01
  18. Reed JK (1985) Deepest distribution of Atlantic hermatypic corals discovered in the Bahamas. Proc 5th Int Coral Reef Symp 6:249–254Google Scholar
  19. Reigl B, Piller WE (2003) Possible refugia for reefs in times of environmental stress. Int J Earth Sci 92:520–531CrossRefGoogle Scholar
  20. Wright DJ (2002) Mapping the seafloor in American Samoa. Geospatial Solutions 12:24–25Google Scholar
  21. Wright DJ (2005) Report of HURL cruise KOK0510: submersible dives and multibeam mapping to investigate benthic habitats of Tutuila, American Samoa. NOAA Tech Rep. NOAA’s Office of Undersea Research Submersible Science Programs, Hawai’i Undersea Research Lab. http://dusk.geo.orst.edu/djl/samoa/hurl/kok0510cruise_report.pdf [Accessed 07/11/2008]
  22. Wright DJ, Donahue BT, Naar DF (2002) Seafloor mapping and GIS coordination at America’s remotest national marine sanctuary (America Samoa). In: Wright DJ (ed) Undersea with GIS. ESRI Press, Redlands, California, pp 33–63Google Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Joint Institute for Marine and Atmospheric ResearchUniversity of Hawaii, Pacific Islands Fisheries Science Center, National Marine Fisheries Service, Kewalo Research FacilityHonoluluUSA
  2. 2.American Samoa Department of Marine and Wildlife ResourcesPago PagoAmerican Samoa

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