The Marine chapter of the 2016 State of the Environment (SoE) report incorporates multiple expert templates developed from
streams of marine data. This metadata record describes the Expert Assessment "The state and trends of quality of habitats
and communities – Seamounts". The full Expert Assessment, including figures and tables (where provided), is attached to
this record. Where available, the Data Stream(s) used to generate this Expert Assessment are accessible through the "On-line
Resources" section of this record.
DESCRIPTION OF HABITAT/COMMUNITY FOR EXPERT ASSESSMENT
Seamounts (undersea mountains, often with volcanic origin) provide ‘oasis’ habitats of hard substratum and are widely considered
to represent sites of elevated biomass and productivity in the deep ocean. Their habitats can support dense aggregations of
corals and associated high biodiversity; these represent vulnerable marine ecosystems (VME) (e.g. UNGA 2006; Clark et al
2011). The geological definition of a seamount (elevation of >1000 m) has no relevance to biodiversity valuation because
smaller features are frequently found to support high, if not the highest, biodiversity. An ecological definition (e.g.
Pitcher et al. 2007) is recommended.
Australia’s marine realm encompasses many seamounts; the best known are the Tasmanian seamounts and the Tasmantid seamount
chain. Additional seamounts have been discovered and mapped on the Lord Howe Rise and the Norfolk Ridge, as well as on Australia’s
southern margin in the GAB.
Seamount communities to ~1500 m depth in the south-east and south-west regions are associated with biogenic habitats formed
mostly by the stony coral Solenosmilia variabilis (Koslow et al 2000; Thresher et al. 2014). Its matrix of dead and life coral,
built up to a layer of at least 1.6 m thickness in places, forms a habitat for other corals, urchins, brittle- and snakestars
and crustaceans (Thresher et al. 2014). Communities and habitats on deeper reaches of seamounts (>1500 m) are less well
studied; they are usually less diverse and sparser, although areas of extraordinary high biomass have been observed in the
south-east region (Thresher et al. 2014). The seamounts in the Tasmantid chain are mapped and well used by various commercial
fisheries, but their epifaunal communities remain poorly documented (Williams et al. 2012).
DATA STREAM(S) USED IN EXPERT ASSESSMENT
This assessment is based on data derived from Marine National Facility Surveys described in MarLIN (http://www.marine.csiro.au/marlin/search.html)
and accessible through the CSIRO Data trawler (http://www.cmar.csiro.au/data/trawler/). Links to specific data sets are provided
in the "On-line resources" section of this record.
• Voyage of Discovery north-west (SS05/2007)
• Voyage of Discovery south-west (SS07/2005 & SS10/2005)
• Tasmanian seamounts surveys (SS01/2000, SS04/2006 & SS02/2007, SS01/2008 & TT01/2008)
• Habitat Mapping (SS01/2000, SS04/2004)
• Habitat and population assessment of giant crabs (2003 - 2005)
• NORFANZ survey of Lord Howe Rise and Norfolk Ridge (TAN0308 - NORFANZ)
2016 SOE ASSESSMENT SUMMARY [see attached Expert Assessment for full details]
• 2016 •
Assessment grade: Very good-Poor
Assessment trend: Stable- Improving
Confidence grade: Adequate high quality evidence and high level of consensus
Confidence trend: Adequate high quality evidence and high level of consensus
Comparability: Grade and trend are somewhat comparable to the 2011 assessment
• 2011 •
Assessment grade: Very good
Assessment trend: Stable
Confidence grade: Limited evidence or limited consensus
Confidence trend: Limited evidence or limited consensus
CHANGES SINCE 2011 SOE ASSESSMENT
There is substantial information on the impact of trawling on seamounts in the South-East Marine Region available.
Anderson, O. F., J. M. Guinotte, A. A. Rowden, M. R. Clark, S. Mormede, A. J. Davies, and D. A. Bowden. 2016. Field validation
of habitat suitability models for vulnerable marine ecosystems in the South Pacific Ocean: Implications for the use of
broad-scale models in fisheries management. Ocean & Coastal Management 120:110-126.
Beaman, R. J., T. C. L. Bridge, C. Lüter, J. Reitner, and G. Wörheide. 2016. Spatial patterns in the distribution of benthic
assemblages across a large depth gradient in the Coral Sea, Australia. Marine Biodiversity.
Clark, M. R., A. A. Rowden, T. A. Schlacher, J. Guinotte, P. K. Dunstan, A. Williams, T. D. O'Hara, L. Watling, E. Niklitschek,
and S. Tsuchida. 2014. Identifying Ecologically or Biologically Significant Areas (EBSA): A systematic method and its application
to seamounts in the South Pacific Ocean. Ocean & Coastal Management 91:65-79.
Dunstan, P., K. , F. Althaus, A. Williams, and N. J. Bax. 2012a. Characterising and Predicting Benthic Biodiversity for
Conservation Planning in Deepwater Environments. PLoS ONE 7:e36558.
Przeslawski, R., A. Williams, S. L. Nichol, M. G. Hughes, T. J. Anderson, and F. Althaus. 2011. Biogeography of the Lord
Howe Rise region, Tasman Sea. Deep Sea Research Part II: Topical Studies in Oceanography 58:959-969.
Schlacher, T. A., A. A. Rowden, J. F. Dower, and M. Consalvey. 2010. Seamount science scales undersea mountains: new research
and outlook. Marine Ecology 31:1-13.
Thresher, R. E., J. Adkins, S. J. Fallon, K. Gowlett-Holmes, F. Althaus, and A. Williams. 2011. Extraordinarily high biomass
benthic community on Southern Ocean seamounts. Nature - Scientific Reports 1:1-5
Williams, A., F. Althaus, M. R. Clark, and K. Gowlett-Holmes. 2011. Composition and distribution of deep-sea benthic invertebrate
megafauna on the Lord Howe Rise and Norfolk Ridge, southwest Pacific Ocean. Deep Sea Research Part II: Topical Studies
in Oceanography 58:948-958.
Williams, A., M. A. P. Green, K. Graham, J. Upston, B. A. Barker, and F. Althaus. 2013. Determining the distribution of
gulper sharks on Australia’s eastern seamount chain and the selectivity of power handine fishing in regard to seamount populations
of Blue-eye Trevalla and Harrisson’s Dogfish. Final Report to AFMA. Hobart.
Williams, A., J. Upston, M. A. Green, and K. Graham. in press. Selective commercial line fishing and biodiversity conservation
co-exist on seamounts in a deepwater marine reserve. Fisheries Research.
Zintzen, V., C. D. Roberts, M. R. Clark, A. Williams, F. Althaus, and P. R. Last. 2011. Composition, distribution and regional
affinities of the deepwater ichthyofauna of the Lord Howe Rise and Norfolk Ridge, south-west Pacific Ocean. Deep Sea Research
Part II: Topical Studies in Oceanography 58:933-947
QUALITY OF DATA USED IN THE ASSESSMENT
CUSTODIAN AND LOCATION OF DATA
CSIRO, data is accessible through the CSIRO Data trawler (see On-line resource links to specific datasets)
METHOD USED TO DETERMINE STATE OR RECENT TREND
Expert assessment of peer reviewed literature and agency reports.
When citing this Expert Assessment in a list of references use the following format:
citation author name/s (year metadata published), metadata title. Citation author organisation/s. File identifier and Data
accessed at (add http link).