%0 Journal Article %J Global Ecology and Biogeography %D 2014 %T Productivity enhances benthic species richness along an oligotrophic Indian Ocean continental margin %A Anna W McCallum %A Skipton N. C. Woolley %A Blażewicz-Paszkowycz, Magda %A Browne, Joanna %A Gerken, Sarah %A Rudy J Kloser %A Gary C. B. Poore %A Staples, David %A Syme, Anna %A Taylor, Joanne %A Walker-Smith, Genefor %A Williams, Alan %A Robin S. Wilson %K Crustaceans %K Leeuwin Current %K macrobenthos %K Peracarida %K POC flux %K polychaetes %K quantitative %X


Aims

Marine soft sediments cover much of the deep ocean and are one of the largest habitats in the world, yet much of our understanding about their diversity is based on sampling in the North Atlantic. The deep-sea benthos provides a simplified environment in which to explore the processes which maintain species richness. Here we investigate the influence of energy and habitat complexity on benthic species richness along an oligotrophic continental margin within the Indian Ocean.


Location

The upper continental margin of western Australia (c. 13–35° S, 100–1000 m depth).
Methods

We examined the species richness of selected polychaetes (Annelida) and crustaceans in sediment grab samples. We used generalized linear models and hierarchical partitioning to examine the relationship and relative importance of temperature, productivity (particulate organic carbon flux, net primary productivity and depth) and habitat complexity (sediment particle size diversity and grain size) on species richness at 51 sites.


Results

In contrast to benthic studies in the North Atlantic, we found that species richness was higher on the shelf than on the slope. Species richness was positively correlated with net primary productivity; this relationship was influenced by high species richness in two areas where oceanic mixing is known to enhance primary productivity. Habitat heterogeneity and temperature were less influential.


Main conclusion

This study represents one of the first extensive quantitative studies of deep-water benthos in the Indo-West Pacific, and provides further evidence that bathymetric gradients of species richness are variable between regions, probably due to variation in local oceanography and productivity regimes. Our findings provide support for the overriding influence of productivity on species richness, even over relatively small ranges in depth and productivity. As climate change is expected to modify biogeochemical fluxes to the deep seafloor, this is likely to affect the communities of deep-sea fauna.


 

%B Global Ecology and Biogeography %P n/a - n/a %8 12 Jan 2014 %G eng %U http://doi.wiley.com/10.1111/geb.12255 %! Global Ecology and Biogeography %R 10.1111/geb.12255 %0 Audiovisual Material %D 2013 %T Seabed multi-beam backscatter mapping of the Australian continental margin %A Keith, G. %A Rudy J Kloser %X

This poster was prepared for the GeoHab 2013 conference, Rome, 6 - 10 May 2013.

The Australian Marine National Facility, RV Southern Surveyor, was fitted with a Simrad EM300 multi-beam echosounder (swath mapper) at the end of 2003. Since then it has been mapping the seafloor around Australia on a variety of research and transit voyages, we have concentrated on mapping the continental margin (100 m – 1500 m) with emphasis on the upper slope (200 m – 700 m depth). This national data set is a useful resource for large scale marine management. Data on key ecological features, such as submarine canyons and seamounts, is available as is information on the distribution of hard and soft substrate that provide habitats suitable for attaching and burrowing fauna, respectively.
 

%G eng %U http://www.geohab2013.it/index.php?lang=en %0 Journal Article %J Acoustics Australia %D 2013 %T Seabed multi-beam backscatter mapping of the Australian continental margin %A Rudy J Kloser %A Keith, G. %X

A multi-beam sonar (MBS) has been used to map Australia’s continental margin seabed from the marine national facility vessel Southern Surveyor on opportunistic transit and research voyages since 2004 with 0.35 M km2 mapped. The MBS data are used to infer key ecological features based on bathymetry (e.g. seamounts, canyons, terraces, banks and deep reefs) and backscatter data for ecological hard (consolidated, e.g. rock for attachment of fauna) and soft (unconsolidated, e.g. mud for burrowing fauna) substrate. Seabed consolidation inference is consistent with a seabed scattering model. To consistently infer ecological significant hard and soft substrate from the backscatter data requires minimisation of errors due to changing absorption (~2 dB) with temperature and depth, calibration drift, changes in pulse length and estimates of area insonified due to seabed slope (<8 dB). Area insonified corrections were required for both across and along-ship slopes. Highest corrections were needed for along-ship slopes in canyon regions and large incidence angles (>60°). A data collection and processing framework is described that works towards a national backscatter mapping program for environmental seabed mapping. Data collected and automated processing for depth, sound absorption and area insonified at level 2 of a possible 5 level data processing hierarchy is available for viewing at http://www.marine.csiro.au/geoserver.

%B Acoustics Australia %V 41 %8 01 Apr 2013 %G eng %U http://www.acoustics.asn.au/joomla/australian-acoustics-journal-april-2013.html#art6 %N 1 %0 Journal Article %J Marine Geology %D 2012 %T Catchment-based classification of Australia's continental slope canyons %A R. Porter-Smith %A Lyne, Vincent D. %A Rudy J Kloser %A Vanessa L Lucieer %K bathome %K biome %K classification %K continental slope %K regionalisation %K Submarine canyons %X This study presents an approach to the classification of submarine canyons on the Australian continental slope. There are many canyons around the Australian continental margin it provides an opportunity to undertake a characterisation and inventory of these potentially important assets. By establishing a shelf, break and foot of slope based on gradient, submarine catchments are defined based on a drainage network derived from across the continental shelf and slope. On completion of this classification, metrics are extracted for both the drainage network representing submarine canyons and the catchment morphology. The rationale for this research is to demonstrate the application of algorithms developed for drainage analysis. These algorithms have traditionally been applied in terrestrial environments for the automatic extraction of drainage networks and catchments from digital elevation models. This work is made possible by recent advances in deep-sea multibeam technology, so that the seafloor morphology can be mapped in higher definition. With the recent advances in data quality, these algorithms can be applied to an integrated and combined model of both elevation and bathymetric datasets to provide better insight into geomorphological features, including the relationships between subaqueous sedimentary canyons, channels and drainage system morphology. Drainage analysis provides a rapid automatic procedure to derive networks on the continental shelf and slope. Results show that by establishing a shelf break and foot of slope based on gradient, submarine catchments can be derived on the continental slope based on the drainage analysis. The Australian continental slope contains 257 shelf-incised catchments based on analysis of a bathymetric model mapped at a resolution of 250 m. The drainage analysis demonstrates the capabilities of correctly predicting the layout of dendritic patterns leading to a better geological understanding. %B Marine Geology %V 303-306 %P 183 - 192 %8 01 Mar 2012 %U http://www.sciencedirect.com/science?_ob=GatewayURL&_method=citationSearch&_eidkey=1-s2.0-S0025322712000400&_origin=SDEMFRASCII&_version=1&md5=9b2f9c142330c49c074697bf785cfb17 %! Marine Geology %R 10.1016/j.margeo.2012.01.008 %0 Journal Article %J Continental Shelf Research %D 2010 %T Multi-beam backscatter measurements used to infer seabed habitats %A Rudy J Kloser %A Penrose, J.D. %A Butler, Alan J. %X Australia; biotopes; epifauna; backscatter; video; multi-beam %B Continental Shelf Research %I Continental Shelf Research %V 30 %P 1772 - 1782 %8 01 Sep 2010 %U http://www.sciencedirect.com/science?_ob=GatewayURL&_method=citationSearch&_uoikey=B6VBJ-50T41PB-1&_origin=SDEMFRASCII&_version=1&md5=0f7040fd7139ca481dc81e5cf6f3870c %N 16 %! Continental Shelf Research %R 10.1016/j.csr.2010.08.004 %0 Audiovisual Material %D 2010 %T National mapping of deepwater biotopes based on multi-beam acoustics %A Rudy J Kloser %A Keith, G. %A Sherlock, Mathew %X

This poster was presented at GeoHab 2010 conference in Wellington NZ, 4 - 7 May 2010.

A program to map the deepwater biotopes of the Australian EEZ is underway based on fine scale acoustic multi-beam echo sounder (MBES) mapping and a newly developed benthic, optical, acoustic grab sampler (BOAGS). Data are collected on specific research voyages as well as utilising transit voyages between ports. These MBES data and associated physical and optical sensing are an important input into assessing key ecological features (e.g. canyons, terraces, banks, seamounts and deep reefs) for regional marine planning, informing the placement of marine protected areas and fisheries spatial management. The acoustic data provide detailed (20 to 50 m grid) bathymetric and inferred substrate information that can be used with other co-variates to predict macro faunal functional groups based on physical and optical “ground truthing”. A consistent approach of interpreting ecological hard and soft substrate based on the acoustic backscatter that maximises the spatial resolution whilst minimises sources of error was developed and applied. This consistent nationally applied acoustic backscatter processing method is highly correlated with visual and physical sampling of the seabed as well as mega fauna diversity. Mega fauna diversity of 6 taxon grouping ~2000 species is highly correlated to both the seabed hardness and the depth of sampling. Nested within a hierarchical classification scheme estimates of seabed hardness are derived for catchments, specific geological features (canyons, seamounts) and MPA’s. Based on this work we propose that seabed hardness as derived from multi-beam acoustics should be included in regional marine planning processes at a number of scales from regional mapping at the 100’s km scale to the 10’s m to 1 km scale for final MPA placement and fisheries spatial management.

Australia’s continental margin defined here from ~150 m to 1500 m, is a narrow strip characterised by high productivity and diversity (Fig. 1). While supporting a major ecological and economic (fishing, oil and gas) resource, this area is poorly-understood yet heavily exploited in parts. A simple first step to assist management of this region is to map the spatial scales of the types of terrain and key components of the biotic assemblages to define marine habitat patches and key ecological features (e.g. canyons, seamounts and deep reefs). Mapping with multi-beam acoustic and optical methods is attractive due to their collective properties: large sampling coverage per unit cost, nondestructive sampling and high spatial resolution.

%G eng %U http://geohab.org/conferences/2010-wellington/ %0 Report %D 2010 %T Scales of habitat heterogeneity and megabenthos biodiversity on an extensive Australian continental margin (100-1,000m depths) %A Williams, Alan %A Althaus, Franziska %A Piers K Dunstan %A Gary C. B. Poore %A Nicholas J. Bax %A Rudy J Kloser %A Felicity McEnnulty %K Biodiversity conservation %K continental slope %K diversity %K hierarchy %K Leeuwin Current %K rarity %K seabed habitat %K spatial scales %X

The first large systematic collection of benthic invertebrate megafauna from the Australian continental margin (depths > 100 m) revealed high species richness and novelty on the south-western continental slope (∼100–1100 m depth; ∼18° S–35° S). A total of 1979 morphologically defined species was discriminated in seven taxa across all samples: Demospongiae, Decapoda, corals (Octocorallia and Antipatharia), Mollusca, Echinodermata, Ascidiacea, and Pycnogonida. Collectively, 59% were estimated to be new or unnamed species. The distribution pattern of megafaunal communities, analysed with a suite of 17 physical covariates, was most influenced at large spatial scales (>100s km) by bottom temperature, oxygen concentration and latitude, whereas at smaller scales (10s of km), seabed type was most influential. Many covariates are driven by the same physical processes and are correlated (e.g. to depth or latitude), thus it is not possible to ascribe causal relationships to fauna distributions. However, their identification highlights the spatial scales that determine the composition of megafaunal communities. Regional-scale transitions in bottom temperature and oxygen concentration are determined by water masses and currents that interact with the south-western margin seabed in different ways depending on location. The nested, smaller-scale heterogeneity of seabed type, classified simply as ‘hard’ or ‘soft’ terrain, differentiates consolidated attachment sites for sessile fauna from sediments suited to mobile and burrowing fauna. Different physical factors affect the distribution of benthic fauna at different scales. Collectively, these patterns of heterogeneity can be represented in a hierarchical framework that consists of biogeographic provinces, biomes, biogeomorphic features, terrains, and finer scales. The Australian government is using a hierarchical approach to identify bioregions for management purposes; a key aim is to ensure that a National Representative System of Marine Protected Areas (NRSMPA) will meet the requirement of comprehensiveness, adequacy and representativeness. Important findings from this study are that the provincial structure of invertebrate megabenthos broadly aligns with the provincial structure derived earlier from the distribution of fishes, but there are differences in the distribution of individual major taxa at both provincial and megahabitat scales. Representative coverage of rarer taxa or narrowly distributed taxa might not be feasible at the same time as ensuring main fauna groups are adequately represented. The hierarchical scales of heterogeneity of the megabenthos in this area, the differences between taxa, and the high proportion of apparently rare species make it clear that it will be as important to manage the area outside the NRSMPA as to manage the NRSMPA itself. Management will be required at different scales that correspond to the multiscale spatial heterogeneity of continental margin fauna.

%I Marine Ecology %U http://www3.interscience.wiley.com/journal/123264322/abstract %0 Journal Article %J Marine Ecology %D 2010 %T Seamount megabenthic assemblages fail to recover from trawling impacts %A Williams, Alan %A Thomas A Schlacher %A Rowden, Ashley A. %A Althaus, Franziska %A Malcolm R Clark %A Bowden, David A. %A Stewart, Robert %A Nicholas J. Bax %A Consalvey, Mireille %A Rudy J Kloser %K benthic megafauna %K conservation management %K deep sea %K diversity %K ecological resilience %K photographic survey %X Because the nature, tempo and trajectories of biological changes that follow the cessation of trawling are unknown for seamounts, it is unclear whether closing them to trawling will lead to a recovery of the fauna and, if so, over what time scales. This paper reports on a ‘test of recovery’ from repeated towed camera surveys on three seamounts off New Zealand in 2001 and 2006 (5 years apart) and three off Australia in 1997 and 2006 (10 years apart). In each region, seamounts where trawling had ceased were compared to adjacent seamounts where trawling was still active, and to seamounts that had never been trawled. If recovery signals existed, the likelihood of detecting them was high because the seamounts were relatively small and topographically simple, and because quantitative survey methods were employed. Multivariate patterns showed no change in the megafaunal assemblage consistent with recovery over a 5–10 year timeframe on seamounts where trawling had ceased. Results based on the number of species and diversity were equivocal, with some cases of increase and decrease on seamounts where trawling had ceased. A few individual taxa were found at significantly higher abundance in the later surveys where trawling had occurred. We suggest this may have resulted from their resistance to the direct impacts of trawling (two chrysogorgid corals and solitary scleractinians), or from protection in natural refuges inaccessible to trawls (unstalked crinoids, two chrysogorgid corals, gorgonians, and urchins). Alternatively, these taxa may represent the earliest stages of seamount recolonisation. They have potential to be dominant for long periods because the pre-trawling composition of benthic assemblages on seamounts includes taxa that grow slowly and/or have an association with ‘thickets’ of a single keystone stony coral (Solenosmilia variabilis) that has generated biogenic habitat over millennia. Resilience of seamount ecosystems dominated by corals is low compared to most other marine systems subject to disturbance by bottom trawling because there are no alternative habitats of the same value for supporting associated species, and because trawling typically removes coral habitat from large areas of individual seamounts. Management to conserve seamount ecosystems needs to account for changing oceanographic conditions (ocean acidification), as well as the direct impacts of human activities such as bottom trawling. Networks of spatial closures that include intact habitats over a range of depths, especially <1500 m, and on clusters and isolated seamounts, may be effective by maintaining the resilience of seamount benthic communities. %B Marine Ecology %I Marine Ecology %V 31 %P 183 - 199 %8 01 Sep 2010 %U http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0485.2010.00385.x/abstract %R 10.1111/j.1439-0485.2010.00385.x %0 Journal Article %J Marine Ecology Progress Series %D 2009 %T Impacts of bottom trawling on deep-coral ecosystems of seamounts are long-lasting %A Althaus, Franziska %A Williams, Alan %A Thomas A Schlacher %A Rudy J Kloser %A Mark Green %A Bruce A Barker %A Nicholas J. Bax %A P Brodie %A Hoenlinger-Schlacher, MA %X trawling impacts, seamounts, deep-sea corals, recovery, conservation, fishing %B Marine Ecology Progress Series %I Marine Ecology Progress Series %V 397 %P 279 - 294 %8 01 Dec 2009 %U http://www.int-res.com/abstracts/meps/v397/p279-294 %! Mar. Ecol. Prog. Ser. %R 10.3354/meps08248 %0 Journal Article %J ICES Journal of Marine Science %D 2009 %T Remarks on “Comment on: Williams et al. (2009) Australia’s deep-water reserve network: implications of false homogeneity for classifying abiotic surrogates of biodiversity, ICES Journal of Marine Science, 66: 214-224” by Peter T. Harris et al %A Williams, Alan %A Nicholas J. Bax %A Rudy J Kloser %X

Australia, benthic habitats, Marine Protected Areas, surrogates

%B ICES Journal of Marine Science %I ICES Journal of Marine Science %V 66 %P 2086 - 2088 %8 01 Dec 2009 %U http://icesjms.oxfordjournals.org/cgi/content/abstract/66/10/2086?maxtoshow=&hits=10&RESULTFORMAT=1&author1=Williams&andorexacttitle=and&andorexacttitleabs=and&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&sortspec=relevance&volume=66&firstpage=2086&reso %N 10 %! ICES Journal of Marine Science %R 10.1093/icesjms/fsp212 %0 Journal Article %J ICES Journal of Marine Science %D 2008 %T Australia’s deep-water reserve network: implications of false homogeneity for classifying abiotic surrogates of biodiversity %A Williams, Alan %A Nicholas J. Bax %A Rudy J Kloser %A Althaus, Franziska %A Bruce A Barker %A Keith, G. %X

Australia, benthic habitats, biodiversity surrogates, classification, deep-sea environments, Marine Protected Areas, surrogates

%B ICES Journal of Marine Science %I ICES Journal of Marine Science %V 66 %P 214 - 224 %8 01 Sep 2008 %U http://icesjms.oxfordjournals.org/cgi/content/full/66/1/214?etoc %N 1 %! ICES Journal of Marine Science %R 10.1093/icesjms/fsn189