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RESEARCH ARTICLE
Contents Vol 60(5)

Bryozoans as southern sentinels of ocean acidification: a major role for a minor phylum

Abigail M. Smith
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- Author Affiliations

Department of Marine Science, University of Otago, PO Box 56, Dunedin 9054, New Zealand. Email: abby.smith@otago.ac.nz

Marine and Freshwater Research 60(5) 475-482 https://doi.org/10.1071/MF08321
Submitted: 25 November 2008  Accepted: 28 January 2009   Published: 25 May 2009

Abstract

Rapid anthropogenic production of CO2 has driven the carbonate chemistry of the sea, causing lowered pH in surface waters. Increasingly, scientists are called on to study ocean acidification and its effects. The ‘minor’ phylum Bryozoa shows considerable potential in understanding temperate southern hemisphere shelf carbonate dynamics, thus complementing tropical studies based mainly on corals. Lowered pH affects skeletons differently depending on their composition, but skeletons are even more strongly affected by morphology. Different bryozoans will manifest the effects of acidification at different times, thus some particularly vulnerable species may act as ‘canaries’ providing an early warning for some shelf communities, such as bryozoan-dominated thickets. A carbonate budget based on several studies of the bryozoan Adeonellopsis in Doubtful Sound, New Zealand, shows that increasing dissolution pressure in cool temperate environments dramatically reduces sediment accumulation rates. Bryozoan shelf carbonate sediments, which blanket the southern shelves of New Zealand and Australia, may serve as biological saturometers, monitoring the effects of acidification over shelf depths. Whether acting as canaries, models or sentinels, bryozoans have great potential to provide insight into the next global challenge: ocean acidification.

Additional keywords: carbonate mineralogy, carbonate sediment, New Zealand, Southern Ocean.


Acknowledgements

Many thanks to Peter Batson and Emily Jones for the use of their photos, to Liz Girvan for unfailing support with the SEM, and to Will Howard for showing me the Deep Bay bryozoans. Professor M. M. Key Jr (Dickinson College), Professor H. G. Spencer (University of Otago) and two anonymous reviewers assisted greatly with their comments on drafts.


References

Batson P. B. (2000). The Otago shelf bryozoan thickets: aspects of their distribution, ecology, and sedimentology. M.Sc. Thesis, University of Otago, Dunedin, New Zealand.

Batson P. B., and Probert P. K. (2000). ‘Bryozoan thickets off Otago Peninsula. New Zealand. Fisheries Assessment Report 2000/46.’ (Ministry of Fisheries: Wellington.)

Bone, Y. , and James, N. P. (1993). Bryozoans as carbonate sediment producers on the cool-water Lacepede Shelf, southern Australia. Sedimentary Geology 86, 247–271.
| Crossref | GoogleScholarGoogle Scholar | Chave K. E. (1964). Skeletal durability and preservation. In ‘Approaches to Paleoecology’. (Eds J. Imbrie and N. Newell.) pp. 377–387. (J. Wiley and Sons: New York.)

Cranfield H. J., Gordon D. P., Willan R. C., Marshall B. A., Battershill C. N. et al. (1998). Adventive marine species in New Zealand. National Institute of Water & Atmospheric Research Technical Report 34, 1–48.

Garey, J. R. , and Schmidt-Rhaesa, A. (1998). The essential role of “minor” phyla in molecular studies of animal evolution. American Zoologist 38, 907–917.
Gordon D. P., and Mawatari S. F. (1992). Atlas of marine-fouling bryozoa of New Zealand ports and harbours. New Zealand Oceanographic Institute Memoirs 107, 1–52.

Gordon D. P., Taylor P. D., and Bigey F. P. (in press). Bryozoa. In ‘New Zealand Inventory of Biodiversity. Volume 1. Kingdom Animalia: Radiata, Lophotrochozoa, and Deuterostomia’. (Ed. D. P. Gordon.) pp. 271–297. (Canterbury University Press: Christchurch.)

Hageman, S. J. , Bock, P. E. , Bone, Y. , and McGowran, B. (1998). Bryozoan growth habits: classification and analysis. Journal of Paleontology 72, 418–436.
Howard W., and Tillbrook B. (2008). ‘Ocean Acidification: Australian Impacts in the Global Context.’ (Australian Department of Climate Change and Antarctic Climate and Ecosystems Cooperative Research Centre: Hobart.)

James, N. P. (1997). The cool-water carbonate depositional realm. SEPM (Society for Sedimentary Geology) Special Publication 56, 1–22.
Junge C. (1998). Bryozoen un Bryozoen-Riff-Strukturen auf dem Kontinentalschelf von Otago/Neuseeland. Diplomarbeit and Diplomkarierung Thesis, Universität Hamburg, Hamburg, Germany.

Kleypas J. A., Feely R. A., Fabry V. J., Langdon C., Sabine C. L., et al. (2006). Impacts of ocean acidification on coral reefs and other marine calcifiers: a guide for future research. In ‘Report of a workshop held 18–20 April 2005, St Petersburg, FL’. Sponsored by NSF, NOAA and the US Geological Survey.

McNeil, B. I. , and Matear, R. J. (2008). Southern Ocean acidification: a tipping point at 450-ppm atmospheric CO2. Proceedings of the National Academy of Sciences 105, 18 860–18 864.
|  CAS | Raven J., Caldeira K., Elderfield H., Hoegh-Guldberg O., Liss P., et al. (2005). ‘Ocean Acidification Due to Increasing Atmospheric Carbon Dioxide. Royal Society Policy Document 12/05.’ (The Royal Society: London.)

Smith A. M. (1993). Bioerosion of bivalve shells in Hauraki Gulf, North Island, New Zealand. In ‘Proceedings of the Second International Temperate Reef Symposium, 7–10 January 1992, Auckland, New Zealand’. (Eds C. N. Battershill, D. R. Schiel, G. P. Jones, R. G. Creese and A. B. MacDiarmid) pp. 175–181. (NIWA Marine: Wellington.)

Smith, A. M. , and Nelson, C. S. (2003). Effects of early sea-floor processes on the taphonomy of temperate shelf skeletal carbonate deposits. Earth-Science Reviews 63, 1–31.
| Crossref | GoogleScholarGoogle Scholar | CAS | Sundquist E. T., and Broecker W. S. (Eds) (1985). ‘The Carbon Cycle and Atmospheric CO2: Natural Variations: Archean to Present.’ (American Geophysical Union: Washington, DC.)

Taylor P. D. (1999). Bryozoans. In ‘Functional Morphology of the Invertebrate Skeleton’. (Ed. E. Savazzi.) pp. 623–645. (John Wiley and Sons: New York.)

Taylor, P. D. , Kudrayavtsev, A. B. , and Schopf, J. W. (2008). Calcite and aragonite distributions in the skeletons of bimineralic bryozoans as revealed by Raman spectroscopy. Invertebrate Biology 127, 87–97.
| Crossref | GoogleScholarGoogle Scholar |

Wejnert, K. E. , and Smith, A. M. (2008). Within-colony variation in skeletal mineralogy of Adeonellopsis sp. (Cheilostomata : Bryozoa) from New Zealand. New Zealand Journal of Marine and Freshwater Research 42, 389–395.
|  CAS |

Young, H. R. , and Nelson, C. S. (1988). Endolithic biodegradation of cool-water skeletal carbonates on Scott Shelf, northwestern Vancouver Island, Canada. Sedimentary Geology 60, 251–267.
| Crossref | GoogleScholarGoogle Scholar |