%0 Journal Article %J Frontiers in Marine Science %D 2020 %T The Fate of Deep-Sea Coral Reefs on Seamounts in a Fishery-Seascape: What Are the Impacts, What Remains, and What Is Protected? %A Williams, Alan %A Althaus, Franziska %A Maguire, Kylie %A Mark Green %A Untiedt, Candice %A Alderslade, Phil %A Malcolm R Clark %A Nicholas J. Bax %A Thomas A Schlacher %K fisheries management %K indicators %K scleractinian coral %K Solenosmilia %K towed-camera %K VME %K vulnerable marine ecosystem %X

Environmental harm to deep-sea coral reefs on seamounts is widely attributed to bottom trawl fishing. Yet, accurate diagnoses of impacts truly caused by trawling are surprisingly rare. Similarly, comprehensive regional assessments of fishing damage rarely exist, impeding evaluations of, and improvements to, conservation measures. Here we report on trawling impacts to deep-sea scleractinian coral reefs in a regional (10–100s of km) fishery seascape off Tasmania (Australia). Our study was based on 148 km of towed camera transects (95 transects on 51 different seamounts with 284,660 separate video annotations and 4,674 “on-seamount” images analysed), and commercial trawling logbook data indexing fishing effort on and around seamounts. We detect trawling damage on 88% (45 of 51) of seamounts. Conversely, intact deep-sea coral reefs persist in refuge areas on about 39% (20 of 51) of the seamounts, and extend onto rocky seabed adjacent to seamounts. Depth significantly shapes the severity of trawl damage. The most profound impacts are evident on shallow seamounts (those peaking in < 950 m depths) where recent and repeated trawling reduced reefs built by scleractinian corals to rubble, forming extensive accumulations around seamount peaks and flanks. At intermediate depths (∼950–1,500 m), trawling damage is highly variable on individual seamounts, ranging from substantial impacts to no detection of coral loss. Deep seamounts (summit depth > 1,500 m) are beyond the typical operating depth of the trawl fishery and exceed the depth range of living deep-sea coral reefs in the region. Accurately diagnosing the nature and extent of direct trawling impacts on seamount scleractinian coral reefs must use stringent criteria to guard against false positive identifications of trawl impact stemming from either (1) misidentifying areas that naturally lacked deep-sea coral reef as areas where coral had been removed, or (2) attributing trawling as the cause of natural processes of reef degradation. The existence of sizeable deep-sea coral reef refuges in a complex mosaic of spatially variable fishing effort suggests that more nuanced approaches to conservation may be warranted than simply protecting untrawled areas, especially when the biological resources with conservation value are rare in a broader seascape context.

%B Frontiers in Marine Science %V 7 %8 25 Sep 2020 %G eng %U https://www.frontiersin.org/article/10.3389/fmars.2020.567002/full %9 Journal %! Front. Mar. Sci. %R 10.3389/fmars.2020.567002 %0 Journal Article %J Diversity and Distributions %D 2020 %T Regional-scale patterns of deep seafloor biodiversity for conservation assessment %A Tim O'Hara %A Williams, Alan %A Althaus, Franziska %A Ross, Andrew S. %A Nicholas J. Bax %E Pirotta, Enrico %K benthos %K conservation assessment %K deep sea %K key ecological features %K rank abundance distribution %X

Aim

Mining and petroleum industries are exploring for resources in deep seafloor environments. Lease areas are often spatially aggregated and continuous over hundreds to thousands of kilometres. Sustainable development of these resources requires an understanding of the patterns of biodiversity at similar scales, yet these data are rarely available for the deep sea. Here, we compare biodiversity metrics and assemblage composition of epibenthic megafaunal samples from deep‐sea benthic habitats from the Great Australian Bight (GAB), a petroleum exploration zone off southern Australia, to similar environments off eastern Australia.

Location

The Great Australian Bight (34–36°S, 129–134°E) and south‐eastern (SE) and north‐eastern (NE) Australian continental margins (23–42°S, 149–155°E) in depths of 1,900–5,000 m.

Methods

A species–sample matrix was constructed from invertebrate and fish megafauna collected from beam trawl samples across regions at lower bathyal (1,900–3,200 m) and abyssal (>3,200 m) depths, and analysed using multivariate, rarefaction and model‐based statistics. We modelled rank abundance distributions (RAD) against environmental factors to identify drivers of abundance, richness and evenness.

Results

Multivariate analyses showed regional and bathymetric assemblage structure across the region. There was an almost complete turnover of sponge fauna between the GAB and SE. SE samples had the highest total faunal abundance and species richness. RAD models linked total abundance and species richness to levels of carbon flux. Evenness was associated with seasonality of net primary production.

Conclusions

Significant assemblage structure at regional scales is reported for the first time at lower bathyal and abyssal depths in the southern Indo‐Pacific region along latitudinal and longitudinal gradients. The GAB fauna was distinct from other studied areas. Relatively high species richness, previously reported from the GAB continental shelf, did not occur at lower bathyal or abyssal depths. Instead, the abundance, richness and evenness of the benthic fauna are linked to surface primary production, which is elevated off SE Australia.

%B Diversity and Distributions %V 1 %8 28 Jan 2020 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1111/ddi.13034 %! Divers Distrib %R 10.1111/ddi.13034 %0 Journal Article %J Frontiers in Marine Science %D 2020 %T True size matters for conservation: deep-sea coral reefs are typically small and estimates of their size are remarkably robust to a method used to define them %A Williams, Alan %A Althaus, Franziska %A Mark Green %A Maguire, Kylie %A Untiedt, Candice %A Mortimer, Nick %A Jackett, Chris J. %A Malcolm R Clark %A Nicholas J. Bax %A Pitcher, Roland %A Thomas A Schlacher %K coral %K deep sea %K fisheries management %K seamount %K Solenosmilia %K towed-camera %K VME %K vulnerable marine ecosystem %X

Protection of vulnerable marine ecosystems (VME) is a critical goal for marine conservation. Yet, in many deep-sea settings, where quantitative data are typically sparse, it is challenging to correctly identify the location and size of VMEs. Here we assess the sensitivity of a method to identify coral reef VMEs based on bottom cover and abundance of the stony coral Solenosmilia variabilis on deep seamounts, using image data from a survey off Tasmania, Australia, in 2018. Whilst there was some detectable influence from varying coral cover and the abundance of live coral heads, the distribution of coral reef VMEs was not substantially shifted by changing these criteria or altering the attributes of a moving window used to spatially aggregate coral patches. Whilst applying stricter criteria for classifying VMEs predictably produced smaller areas of coral reef VME, these differences were not sizeable and were often negligible. Coral reef VMEs formed large contiguous “blankets,” mainly on the peaks and flanks of seamounts, but were absent from the continental slope where S. variabilis occurred at low abundance (cover) and/or had no living colonies. The true size of the Tasmanian coral reef VMEs ranged from 0.02 to 1.16 km2 ; this was relatively large compared to reefs of S. variabilis mapped on New Zealand seamounts, but is small compared to the scales used for regional model predictions of suitable habitat (typically 1 km2 grid cell), and much smaller than the smallest units of management interest (100s–1000s km2 ). A model prediction of the area of suitable habitat for coral reef in the Tasmanian area was much greater than the area of coral reef estimated in this study. That the method to estimate VME size is not overly sensitive to the choice of criteria is highly encouraging in the context of designing spatial conservation measures that are robust, although its broader application, including to other VME indicator taxa, needs to be substantiated by scenario testing in different environments. Importantly, these results should give confidence for stakeholder uptake and form the basis for better predictive VME models at larger spatial scales and beyond single taxa.

%B Frontiers in Marine Science %V 7 %8 3 Apr 2020 %G eng %U https://www.frontiersin.org/article/10.3389/fmars.2020.00187/full %9 Journal %! Front. Mar. Sci. %R 10.3389/fmars.2020.00187 %0 Journal Article %J Ecological Indicators %D 2018 %T Developing indicators and a baseline for monitoring demersal fish in data-poor offshore Marine Parks using probabilistic sampling %A Nicole A. Hill %A Neville Barrett %A Jessica H. Ford %A David Peel %A Scott D Foster %A E Lawrence %A Jacquomo Monk %A Althaus, Franziska %A K Hayes %K Baited Remote Underwater Videos (BRUV) %K Generalised Random Tessellation Stratified (GRTS) sampling %K Marine Protected Area (MPA) %K Spatially-balanced sampling %X

The number of Marine Protected Areas (MPAs) has increased globally as concerns over the impact that human activities are having on the world’s oceans have also increased. Monitoring is a key requirement to determine if MPAs are meeting their objectives. However, many recently declared MPA’s are large, offshore, or form part of an expansive network and spatial information about the habitats, communities and species that they contain is often lacking. This presents challenges for deciding exactly what to monitor and developing strategies on how to monitor it efficiently. Here we examine these issues using the Flinders Marine Park in Australia as a case study. We trial a two-stage version of a spatially-balanced, probabilistic sampling design combined with Baited Remote Underwater Videos (BRUVs) to perform an initial inventory, and we evaluate the potential of six commercially and ecologically important demersal fish as indicators within the Marine Park. Using this approach we were able to (1) quantitatively describe the distribution of the fish species in the Marine Park; (2) establish quantitative and representative estimates of their abundance throughout the Marine Park to serve as a baseline for future monitoring; (3) conduct power analyses to estimate the magnitude of increase we may be able to detect with feasible levels of sampling effort. Power analysis suggested that for most of our potential indicator species, detecting increases in abundance as small as 50% from present values should be feasible if sampling is restricted to a species’ preferred habitat and the same sites are sampled through time. Our approach is transferrable to other regions where monitoring programs must be designed based on limited spatial and biological data, assisting with decisions on what and how to monitor.

%B Ecological Indicators %V 89 %P 610 - 621 %8 01 Jun 2018 %G eng %U http://linkinghub.elsevier.com/retrieve/pii/S1470160X18301249 %! Ecological Indicators %R 10.1016/j.ecolind.2018.02.039 %0 Report %D 2018 %T Field manuals for marine sampling to monitor Australian waters %A Rachel Przeslawski %A Scott D Foster %A Vanessa L Lucieer %A Jacquomo Monk %A Phil J. Bouchet %A Tim J. Langlois %A Andrew Carroll %A Joel Williams %A Neville Barrett %A Althaus, Franziska %A Beaman, Robin J. %A Berents, Penny %A Tom Bridge %A Malcolm R Clark %A Jamie Colquhoun %A Leanne M. Currey Randall %A Graham J. Edgar %A Fellows, Melissa %A Frid, Chris %A Friedman, Ariell %A Daniel C Gledhill %A Jordan S. Goetze %A David Harasti %A K.R. Hayes %A Nicole A. Hill %A G.R. Hosack %A Charlie Huveneers %A Ierodiaconou, Daniel %A T Ingleton %A Alan Jordan %A Gary A. Kendrick %A Kennedy, David M. %A E Lawrence %A Tom B. Letessier %A Linklater, Michelle %A Lowry, Michael %A Hamish A. Malcolm %A Jessica J. Meeuwig %A Scott L Nichol %A Tim O'Hara %A K Picard %A Alix Post %A Matthew J Rees %A Santana-Garcon, Julia %A Scott, Molly %A Justy P W Siwabessy %A Smith, Jodie %A Marcus Stowar %A Taylor, Matt %A Thompson, Christopher %A Maggie Tran %A Tyndall, Aaron %A Laurent, Vigliola %A Sasha Whitmarsh %K monitoring %K standard operating procedures %K survey methods %X

Australia has one of the world’s largest marine estates that includes many vulnerable habitats and a high biodiversity, with many endemic species crossing a wide latitudinal range. The marine estate is used by a variety of industries including fishing, oil & gas, and shipping, in addition to traditional, cultural, scientific and recreational uses. The Commonwealth government has recently established the Australian Marine Parks (AMPs), the largest network of marine protected areas in the world, complementing existing networks in State and Territory waters.

Monitoring the impacts of these uses on the marine environment is a massive shared responsibility that can only be achieved by making the best use of all the information that is collected. Australia now has a number of significant long-term marine monitoring and observing programs, as well as a national ocean data network. Without some common and agreed standards, much of the information collected will not be comparable with other areas or sectors. This may reduce its value to regional and national management, while the individual project or survey may lose the opportunity to interpret results in a regional or national context.

We have therefore developed a suite of field manuals for the acquisition of marine benthic (i.e. seafloor) data from a variety of frequently-used sampling platforms so that data can become directly comparable in time and through space, thus supporting nationally relevant monitoring in Australian waters and the development of a monitoring program for the AMP network. This objective integrates with one of the eight high-level priorities identified by the National Marine Science Plan (2015-25): the establishment of national baselines and long-term monitoring.


Related information

%8 01 Feb 2018 %G eng %0 Report %D 2017 %T Biological and habitat feature descriptions for the continental shelves of Australia’s temperate-water marine parks- including collation of existing mapping in all AMPs %A Jacquomo Monk %A Joel Williams %A Neville Barrett %A Alan Jordan %A Vanessa L Lucieer %A Althaus, Franziska %A Scott L Nichol %K AMP %K biodiversity patterns %K Habitat mapping %K knowledge synthesis %K reef habitat %X

Understanding the distribution of reef habitats and associated biota on the continental shelf is important for managing Australia’s Marine Park (AMP) network. This is because reef habitats on the continental shelf are highly productive when compared abysal habitats, and are often subjected to disproportionate pressures from fishing, oil and gas and shipping sectors. This report documents the collation, synthesis and location of publically available datasets describing the distribution of reef habitats and associated sessile and mobile biota on the continental shelf regions of AMPs in the Temperate east, South-east, and South-west marine planning regions. Additionaly, this project has also been the identification of key gaps in our understanding of the physical mapping and sampling of reef-affiliated biota to assist in the prioritisation of future research programmes.

%8 09 Mar 2017 %G eng %0 Journal Article %J Progress in Oceanography %D 2017 %T A conceptual surrogacy framework to evaluate the habitat potential of submarine canyons %A Z Huang %A Thomas A Schlacher %A Scott L Nichol %A Williams, Alan %A Althaus, Franziska %A Kloser, Rudy %K continental margin %K Fauna environmental association %K Habitat diversity %K Niches %K Predictions %K Spatial planning %X

The seascape of the vast Australian continental margin is characterised by numerous submarine canyons that represent an equally broad range of geomorphic and oceanographic heterogeneity. Theoretically, this heterogeneity translates into habitats that may vary widely in their ecological characteristics. Here we describe the methodology to develop a framework to broadly derive estimates of habitat potential for pelagic and epibenthic species (including demersal fishes), and benthic infauna in all of Australia’s known submarine canyons. Our analysis shows that the high geomorphic and oceanographic diversity of Australian submarine canyons creates a multitude of potential habitat types. In general, it appears that canyons may be particularly important habitats for benthic species. Canyons that incise the shelf tend to score higher in habitat potential than those confined to the slope. Canyons with particularly high habitat potential are located mainly offshore of the Great Barrier Reef and the NSW coast, on the eastern margin of Tasmania and Bass Strait, and on the southern Australian margin. Many of these canyons have complex bottom topography, are likely to have high primary and secondary production, and have less intense disturbance to sediment. The framework presented here can be applied – once refined and comprehensively validated with ecological data – to help managers make informed conservation decisions, especially for high value canyons.

%B Progress in Oceanography %8 01 Jan 2017 %G eng %U http://linkinghub.elsevier.com/retrieve/pii/S0079661117301817 %! Progress in Oceanography %R 10.1016/j.pocean.2017.11.007 %0 Report %D 2016 %T Analysis of Approaches for Monitoring Biodiversity in Commonwealth Waters - Field work report %A Althaus, Franziska %A Neville Barrett %A Jeffrey M Dambacher %A P Davies %A Renata Ferrari %A Jessica H. Ford %A Keith R Hayes %A Nicole A. Hill %A G.R. Hosack %A Renae Hovey %A Z Huang %A J Hulls %A T Ingleton %A Alan Jordan %A Gary A. Kendrick %A Johnathan T. Kool %A E Lawrence %A Leeming, Rhys %A Vanessa L Lucieer %A Hamish A. Malcolm %A Meyer, L %A Jacquomo Monk %A Scott L Nichol %A David Peel %A Nicholas R. Perkins %A Justy P W Siwabessy %A Sherlock, M %A Martin, Tara %A Maggie Tran %A Walsh, A %A Williams, Alan %X

The overall objective of this project was to contribute to a blue-print for a sustained national environmental monitoring strategy for monitoring biodiversity in the Commonwealth Marine Areas. The approach would apply to Key Ecological Features (KEFs) and the Commonwealth Marine Reserve (CMR) Network, focusing initially on the Southeast Marine Region. CMRs and KEFs are large, remote and poorly known, so this project focussed on identifying flexible, statistically robust approaches to survey design and data collection that could result in comprehensive descriptions of the surveyed area and at the same time provide a statistical baseline for future repeat surveys in the same area. Given the conservation status and values of these areas, non-destructive sampling tools were prioritized, including remote sensing using acoustics (e.g. multibeam) that provide information on seafloor characteristics (bathymetry, hardness and texture), and direct observation using video and camera stills, taken by towed units, autonomous units or baited units. The final report is of necessity highly technical, reporting on the design and analytical issues addressed by this project. This executive summary is designed to provide an overview of the project and highlight the key findings relevant to policy makers and managers, omitting most of the technical detail. Readers interested in technical detail are referred to the main body of this report or the many research papers resulting from this work that are listed at the end of this summary.

Three field programs were undertaken. The largest survey was for the Flinders Commonwealth Marine Reserve (CMR) located offshore, northeast of Tasmania. This provided a baseline of the continental shelf, in the multiple use zone of this reserve, on which future monitoring can be built, and provides an initial characterization of the upper slope areas in the same zone of this CMR. A smaller survey targeted at known shelf reefs features in the Solitary Islands Marine Park (SIMP) and Solitary Islands Marine Reserve (SIMR) was designed to address specific sampling issues including: extending State-based research to this Commonwealth KEF, comparing autonomous and towed platforms for capturing video imagery, and examining statistical issues associated with the use of baited underwater remote videos (BRUVs). The third survey in the KEF east of the Houtman-Abrolhos islands was an exploratory survey designed to identify whether coral-kelp and other shelf reef communities in the State MPA extended into this KEF, and explore whether seabird diet could be used as a reliable indicator of pelagic ecosystem health.


 

%8 01 May 2016 %G eng %0 Journal Article %J Oceanography and Marine Biology: Annual Review %D 2016 %T Perspectives in visual imaging for marine biology and ecology: from acquisition to understanding %A Durden, J %A Schoening, T %A Althaus, Franziska %A Friedman, Ariell %A Garcia, R %A Glover, A G %A Greinert, J %A Stout, J %A Jones, J O B %A Jordt, A %A Kaeli, W %A Koser, K %A Kuhnz, L A %A Lindsay, D %A Nattkemper, T W %A Osterloff, J %A Ruhl, H A %A Singh, H %A Maggie Tran %A Morris, K J %A Bett, B J %K image annotation %K imaging technology %K marine imaging %K Survey design %X

Marine visual imaging has become a major assessment tool in the science, policy and public understanding of our seas and oceans. The technology to acquire and process this imagery has significantly evolved in recent years through the development of new camera platforms, camera types, lighting systems and analytical software. These advances have led to new challenges in imaging, including storage and management of ‘Big Data’, enhancement of digital photos, and the extraction of biological and ecological data. The need to address these challenges, within and beyond the scientific community, is set to substantially increase in the near future, as imaging is increasingly used in the designation and evaluation of marine conservation areas, and for the assessment of environmental baselines and impact monitoring of various marine industries. We review the state of the theory, techniques and technologies associated with each of the steps of marine imaging for observation and research, and to provide an outlook on the future from the perspective of current active science and engineering developers and users.

%B Oceanography and Marine Biology: Annual Review %V 54 %P 1-72 %8 17 Dec 2016 %G eng %U http://doi.org/10.5281/zenodo.202685 %R http://doi.org/10.5281/zenodo.202685 %0 Journal Article %J Journal of Applied Ecology %D 2015 %T The cumulative effect of trawl fishing on a multispecies fish assemblage in south-eastern Australia %A Scott D Foster %A Piers K Dunstan %A Althaus, Franziska %A Williams, Alan %E Punt, Andre %K cumulative impacts %K ecosystem-based fisheries management %K fish assemblage %K multispecies %K Species archetype model %K species traits %K trawl fishing %X

Summary

  1.  Understanding the effect of anthropogenic pressure on animal assemblages over time is a challenging problem that integrates human activities and community ecology. Our ability to make informed decisions for managing pressures depends on estimating their ecological effects, and a rigorous and objective approach should be used. There are three requirements for this type of approach to be successful: sufficient biological and ecological data, congruent data describing human activity and an appropriate statistical method that can link the ecological information to the pressures.
  2. In this work, we explore the effects of cumulative bottom-trawl fishing on fish assemblages over a 20-year period. The analysis captures assemblage responses during the early period of the fishery's development and shows the changes in the abundance of many species as a small and coherent set of ‘archetypical’ responses to cumulative pressure.
  3.  The effect of the cumulative pressure is heterogeneous: some archetypical responses show consistent decline with increased fishing effort, some are less sensitive, and some show an increase in abundance.
  4.  Some, but not all, archetypical response groups are composed of species with similar ecological and life-history traits. Most obviously, the archetype showing greatest decline in abundance is made up of species that have the highest mean values of generation time, oldest age at maturity and longest life span.
  5.  Applications of the methods include identifying spatially explicit system-level trade-offs – between species, species groups (archetypes) and fishery subareas – for ecosystem-based management.
  6.  Synthesis and applications The impact of fishing pressure, accumulated over time, induces heterogeneous patterns of change in fish assemblage composition. The patterns of change are grouped into ‘archetypical response groups’ to provide an interpretable and robust description. The composition of the species groups show that life-history traits are indicative but do not always provide a complete description of how a species might respond to the pressure.
%B Journal of Applied Ecology %V 52 %P 129 - 139 %8 01 Feb 2015 %G eng %U http://doi.wiley.com/10.1111/1365-2664.12353 %N 1 %! J Appl Ecol %R 10.1111/1365-2664.12353 %0 Journal Article %J PLOS ONE %D 2015 %T A standardised vocabulary for identifying benthic biota and substrata from underwater imagery: the CATAMI classification scheme %A Althaus, Franziska %A Nicole A. Hill %A Renata Ferrari %A Edwards, Luke %A Rachel Przeslawski %A Schönberg, Christine H. L. %A Rick D Stuart-Smith %A Neville Barrett %A Graham J. Edgar %A Jamie Colquhoun %A Maggie Tran %A Alan Jordan %A T Rees %A Karen Gowlett-Holmes %E Judi E Hewitt %X

Imagery collected by still and video cameras is an increasingly important tool for minimal impact, repeatable observations in the marine environment. Data generated from imagery includes identification, annotation and quantification of biological subjects and environmental features within an image. To be long-lived and useful beyond their project-specific initial purpose, and to maximize their utility across studies and disciplines, marine imagery data should use a standardised vocabulary of defined terms. This would enable the compilation of regional, national and/or global data sets from multiple sources, contributing to broad-scale management studies and development of automated annotation algorithms. The classification scheme developed under the Collaborative and Automated Tools for Analysis of Marine Imagery (CATAMI) project provides such a vocabulary. The CATAMI classification scheme introduces Australian-wide acknowledged, standardised terminology for annotating benthic substrates and biota in marine imagery. It combines coarse-level taxonomy and morphology, and is a flexible, hierarchical classification that bridges the gap between habitat/biotope characterisation and taxonomy, acknowledging limitations when describing biological taxa through imagery. It is fully described, documented, and maintained through curated online databases, and can be applied across benthic image collection methods, annotation platforms and scoring methods. Following release in 2013, the CATAMI classification scheme was taken up by a wide variety of users, including government, academia and industry. This rapid acceptance highlights the scheme’s utility and the potential to facilitate broad-scale multidisciplinary studies of marine ecosystems when applied globally. Here we present the CATAMI classification scheme, describe its conception and features, and discuss its utility and the opportunities as well as challenges arising from its use.

%B PLOS ONE %V 10 %P e0141039 %8 10 Apr 2017 %G eng %U http://dx.plos.org/10.1371/journal.pone.0141039 %N 10 %! PLoS ONE %R 10.1371/journal.pone.0141039 %0 Journal Article %J Zootaxa %D 2014 %T Australia’s deep-water octocoral fauna: historical account and checklist, distributions and regional affinities of recent collections %A Alderslade, Philip %A Althaus, Franziska %A Felicity McEnnulty %A Karen Gowlett-Holmes %A Williams, Alan %X

The number of deep-water (>80 m) octocoral species recorded from Australian waters has more than tripled from 135 to 457 following six surveys undertaken between 1997 and 2008 on the deep continental margin of south-eastern, western and north-western Australia and the Tasman Sea.  This rapid increase in knowledge follows a slow accumulation of records since the earliest collections were made by vessels such as the Géographe and the Naturaliste in the early years of the 19th century. Consistent identification and alpha-labelling of the octocoral fauna between surveys has permitted a multi-region description and comparison.  We detail the identities, distributions and regional affinities of 457 octocoral species in 131 genera and 28 families from the orders Alcyonacea and Pennatulacea, including 69 new species, 17 new genera and 43 first records for Australia. Five of the more common genera were widely distributed (present at 35 and 66 sampling stations spanning all of the 4 survey regions), but two were restricted to south-eastern Australia—Pleurogorgia Versluys, 1902 and Tokoprymno Bayer, 1996—and were only sampled from depths below 700 m.  The great majority of species (81%) and nearly half of all genera (47%) were only sampled once or twice.  The highest average number of species per sampling station (3.2) was reported from the outer shelf. The proportion of new species was highest (>22%) on the upper and lower slope bathomes, intermediate (13–15%) on the mid-slope bathome and lowest (8%) on the outer shelf bathome.  Species overlap between bathomes was low, but all families were shared across bathomes. Most described species (55 of 69) have an Indo-West Pacific affinity, 20 have an Indian Ocean affinity, while three were previously recorded from the Atlantic Ocean only; 20 appear to be Australian endemics. Octocorals can now be added to an emerging set of taxon-specific data sets—including fishes, ophiuroids and galatheids—that permit regional-scale analysis of biodiversity distributions to support Australia’s efforts in marine conservation management. However, because so much of the world octocoral literature is inadequate for accurate identifications to species level, there is a pressing need for taxonomic revisions using modern morphological and molecular techniques to fine-tune the current use of octocorals as indicators of vulnerable marine ecosystems in many national and high seas conservation initiatives.
 

%B Zootaxa %V 3796 %P 435 %8 20 May 2014 %G eng %U http://biotaxa.org/Zootaxa/article/view/zootaxa.3796.3.2 %N 3 %! Zootaxa %R 10.11646/zootaxa.3796.3.2 %0 Audiovisual Material %D 2014 %T Putting names to a sea of faces - standardising the flora and fauna classification of Australian marine images (CATAMI) %A Althaus, Franziska %A Annabel Ozimec %X

This poster explains the system of standardising the flora and fauna classification of Australian marine images using Collaborative and Automated Tools for the Analysis of Marine Imagery and video (CATAMI)

CATAMI, a collaborative national project, has devised a common language for identifying and naming marine life pictured in underwater photographs and video. The system employs a standardised combination of high-level taxonomy (phylum, order, class) and morphological (shape, growth-form) characteristics that can be determined from a picture. This provides greater consistency than traditional classification approaches that rely on the handling of specimens.

Put more simply, photographs and video provide a safe, non-destructive and efficient way to examine and monitor marine habitats. To be useful on a national scale, however, all the life forms they reveal must be named in a consistent way. A new classification system devised by Australia’s CATAMI project provides that common language.

This poster is based on the original pictorial guide produced by CATAMI project partners and contributors:

http://www.nerpmarine.edu.au/document/catami-classification-scheme-scoring-marine-biota-and-substrata-underwater-imagery

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%8 01 Apr 2014 %G eng %0 Generic %D 2013 %T CATAMI Classification Scheme for scoring marine biota and substrata in underwater imagery - A pictorial guide to the Collaborative and Annotation Tools for Analysis of Marine Imagery and Video (CATAMI) classification scheme %A Althaus, Franziska %A Nicole A. Hill %A Edwards, L %A Renata Ferrari %X

This is a picture-based guide designed to promote national consistency and standards for classifying marine biota and substrata captured in underwater imagery. National consistency is an important requirement for effective monitoring of benthic ecosystems in Commonwealth Marine Reserves and key ecological features (implementing Marine Bioregional Plans).

This document provides definitions and examples for the categories described in Version 1.2 of the CATAMI Classification Scheme for marine biota and substrata in underwater imagery (CATAMI Technical Working Group, 2013). It is envisaged that imagery from a range of sources, including video and digital stills and hence spanning a range in resolution and quality, will be scored using this system.

The classification scheme was designed to allow images from shallow waters to abyssal depths and from the tropics to Antarctic/ Arctic waters to be classified using the same labels, i.e. a set of consistent identifiers. For ease of tracking and data-basing, each standardised label was also assigned a CAAB ‘code’. CAAB stands for Codes for Australian Aquatic Biota and is a numerical code that is listed, described and maintained through a CSIRO website at (http://www.cmar.csiro.au/caab/). Originally CAAB were only used for taxonomic classification of biota, but the system was adapted to encompass both the physical and the biota classes of the CATAMI classification.

The publication is by CATAMI but has been facilitated through funds from CATAMI (ANDS & NECTAR), NERP and researchers  ‘in kind’ by their institutions.

Related information:

%G eng %U http://catami.github.io/catami-docs/CATAMI%20class_PDFGuide_V4_20141218.pdf %0 Journal Article %J Marine Ecology %D 2013 %T Environmental predictors of decapod species richness and turnover along an extensive Australian continental margin (13–35° S) %A Anna W McCallum %A Gary C. B. Poore %A Williams, Alan %A Althaus, Franziska %A Tim O'Hara %K Biodiversity %K Biogeography %K environmental gradients %K latitudinal gradients %K species turnover %K Western Australia %X

The use of environmental data in biogeographic studies of the deep sea is providing
greater insight into the processes underlying large-scale patterns of
diversity. Recent surveys of Australia’s western continental margin (~100–
1100 m) provide systematic sampling of invertebrate megafauna along a gradient
of 22° of latitude (13–35° S). Diversity patterns of decapod crustaceans
were examined and we investigated the relative importance of environmental
and spatial predictor variables on both species richness (alpha diversity) and
species turnover. Distance-based linear models (DistLM) indicated a suite of
variables were important in predicting species turnover, of which temperature
and oxygen were the most influential. These reflected the oceanographic features
that dominate distinct depth bathomes along the slope. The numbers of
species within samples were highly variable; a small but significant increase in
diversity towards the tropics was evident. Replicated sampling along the margin
at ~100 m and ~400 m provided an opportunity to compare latitudinal patterns
of diversity at different depths. On the shallow upper slope (~400 m)
temperature was disassociated from latitude and the latter proved to be the
best predictor of sample species richness. The predictive power of latitude over
other variables indicates that proximity to the highly diverse Indo-West Pacific
(IWP) may be important, especially considering that almost 40% of species in
this study had a wide IWP distribution. In the management of Australia’s marine
environments, geomorphic surrogates have been emphasised when defining
areas for protection. We found sea-floor characteristics were relatively less
important in predicting richness or community composition.

%B Marine Ecology %P n/a - n/a %8 01 Mar 2013 %U http://onlinelibrary.wiley.com/doi/10.1111/maec.12016/abstract %! Mar Ecol %R 10.1111/maec.12016 %0 Journal Article %J PLoS ONE %D 2012 %T Characterising and predicting benthic biodiversity for conservation planning in deepwater environments %A Piers K Dunstan %A Althaus, Franziska %A Williams, Alan %A Nicholas J. Bax %A Bograd, Steven J. %X

Understanding patterns of biodiversity in deep sea systems is increasingly important because human activities are extending further into these areas. However, obtaining data is difficult, limiting the ability of science to inform management decisions. We have used three different methods of quantifying biodiversity to describe patterns of biodiversity in an area that includes two marine reserves in deep water off southern Australia. We used biological data collected during a recent survey, combined with extensive physical data to model, predict and map three different attributes of biodiversity: distributions of common species, beta diversity and rank abundance distributions (RAD). The distribution of each of eight common species was unique, although all the species respond to a depth-correlated physical gradient. Changes in composition (beta diversity) were large, even between sites with very similar environmental conditions. Composition at any one site was highly uncertain, and the suite of species changed dramatically both across and down slope. In contrast, the distributions of the RAD components of biodiversity (community abundance, richness, and evenness) were relatively smooth across the study area, suggesting that assemblage structure (i.e. the distribution of abundances of species) is limited, irrespective of species composition. Seamounts had similar biodiversity based on metrics of species presence, beta diversity, total abundance, richness and evenness to the adjacent continental slope in the same depth ranges. These analyses suggest that conservation objectives need to clearly identify which aspects of biodiversity are valued, and employ an appropriate suite of methods to address these aspects, to ensure that conservation goals are met.

%B PLoS ONE %V 7 %P e36558 %8 01 May 2012 %U http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036558 %N 5 %! PLoS ONE %R 10.1371/journal.pone.0036558 %0 Book Section %B Seafloor Geomorphology as Benthic Habitat %D 2012 %T Evaluating Geomorphic Features as Surrogates for Benthic Biodiversity on Australia’s Western Continental Margin %A Althaus, Franziska %A Williams, Alan %A Kloser, Rudy J. %A Seiler, Jan %A Nicholas J. Bax %K epifauna %K hierarchical habitat classification %K video data %K Western Australia %X

Australia's western continental margin extends over∼2,000 km, from subtropical to temperate latitudes (∼18–35ºS). The regional oceanography overlying the deep continental shelf and slope area (∼100–1,000 m depths) is profoundly influenced by the southward-flowing Leeuwin current (LC) to depths of ∼300 m, and by a northward-flowing counter-current, the Leeuwin Undercurrent (LUC) below those depths. The LC is characterized by warm, low-salinity, low-productivity waters, whereas the LUC is characterized by colder more oxygenated waters. The role of these features as ecological habitats and their potential as surrogates for biodiversity were examined in the context of a hierarchical habitat classification scheme used by Last et al. to define bioregions for marine management planning in Australian waters. Associations of epibenthic megafauna with habitats along Australia's western margin were evaluated quantitatively summarizing the presence/absence scores of 11 fauna types in the video frames into percentage occurrences of dominant fauna for each sample. The scored fauna types were: sessile fauna absent, bioturbators, anemones, seapen, stalked sponge, ascidians, bryozoa, crinoids, sponges, coral, and coral (reef); all scored at low or high abundance. It is necessary to have information at coarser scales to provide ecologically meaningful context, while information at finer scales provides ecologically meaningful detail.

Book: https://www.elsevier.com/books/seafloor-geomorphology-as-benthic-habitat/harris/978-0-12-385140-6

%B Seafloor Geomorphology as Benthic Habitat %I Elsevier %P 665 - 679 %@ 9780123851406 %G eng %U https://linkinghub.elsevier.com/retrieve/pii/B9780123851406000487 %& 48 %R 10.1016/B978-0-12-385140-6.00048-7 %0 Journal Article %J Diversity and Distributions %D 2012 %T Identifying hotspots for biodiversity management using rank abundance distributions %A Piers K Dunstan %A Nicholas J. Bax %A Scott D Foster %A Williams, Alan %A Althaus, Franziska %K Biodiversity %K hotspot %K Prediction %K rank abundance distribution %X

Identification of biodiversity hotspots has typically relied on species richness. We extend this approach to include prediction to regional scales of other attributes of biodiversity based on the prediction of Rank Abundance Distributions (RADs). This allows us to identify areas that have high numbers
of rare species and areas that have a rare assemblage structure.

%B Diversity and Distributions %V 18 %P 22 - 32 %8 01 Jan 2012 %G eng %U http://doi.wiley.com/10.1111/j.1472-4642.2011.00838.x %N 1 %R 10.1111/j.1472-4642.2011.00838.x %0 Journal Article %J Deep Sea Research Part II: Topical Studies in Oceanography %D 2011 %T Biogeography of the Lord Howe Rise region, Tasman Sea %A Rachel Przeslawski %A Williams, Alan %A Scott L Nichol %A Hughes, Michael G. %A Tara J Anderson %A Althaus, Franziska %K Lord Howe Plateau; Southwest Pacific; Endemism; Oceanography; Geology; Geomorphology %X

The two principal aims of this study were to synthesise physical and biological information to characterise the Lord Howe Rise (LHR) region and to use recent survey collections of benthic invertebrates (mostly large benthic epifauna) to describe its biogeography at regional and sub-regional scales. The LHR region is large (1.95 million km2), spans tropical and cool temperate latitudes (18.4 to 40.3°S), and is influenced by several ocean currents, notably the East Australian Current and the Tasman Front. Our analyses revealed that biological patterns were related to two groups of geomorphic morphotypes found in this topographically complex region: subdued bathymetric features (expansive soft sediment basins and plateaus) and raised bathymetric features (scattered seamounts, guyots, knolls, and pinnacles). Raised bathymetric features in the LHR region were more likely to support richer and more abundant epifaunal assemblages dominated by suspension feeding invertebrates on hard substrata compared to subdued features which were dominated by infauna and detritivores in soft sediments. However, this trend does not apply to all raised bathymetric features (e.g., Gifford Guyot), with variations in depth, elevation, latitude, and particularly substrata affected the composition of biological assemblages. In addition, some demersal fishes, ophiuroids, and other benthic invertebrates showed distinct north-south delineations that coincide with the influence of the Tasman Front and thermal gradients. While the lack of spatially- and temporally- replicated data in the region limits our interpretation of survey data, paleo-environmental processes and examples from other regions provide some indication of how dispersal influences migration, speciation, and endemism in the LHR region. Although our current knowledge is limited, it is hoped that this review will help inform future studies in the area, as equitable examination of biological, geological, and oceanographic characteristics will facilitate future assessments of LHR biogeography and permit the inclusion of this region in biogeographic studies with a national or global context.

%B Deep Sea Research Part II: Topical Studies in Oceanography %I Deep Sea Research II (Lord Howe special issue) %V 58 %P 959 - 969 %8 01 Apr 2011 %U http://www.sciencedirect.com/science/article/pii/S0967064510003516 %N 7-8 %! Deep Sea Research Part II: Topical Studies in Oceanography %R 10.1016/j.dsr2.2010.10.051 %0 Journal Article %J Deep Sea Research Part II: Topical Studies in Oceanography %D 2011 %T Composition and distribution of deep-sea benthic invertebrate megafauna on the Lord Howe Rise and Norfolk Ridge, southwest Pacific Ocean %A Williams, Alan %A Althaus, Franziska %A Malcolm R Clark %A Karen Gowlett-Holmes %K Biodiversity conservation %K Biogeography %K Coral Sea %K NORFANZ voyage %K Tasman Sea %K Taxonomy %X

The deep-sea biodiversity of the Lord Howe Rise and Norfolk Ridge – two complex submarine features that extend in a north-south direction either side of a deep basin within the northern Tasman Sea and southern Coral Sea – was sampled in 2003 for the first time on a broad regional scale. The total of 1313 megabenthic invertebrate species from 17 higher order taxa collected between 100 and 1800 m depths showed faunal diversity and novelty was high. Only 256 of these species were named, and 10% of these were described as a result of this survey; 78% are un-named and believed to be mostly new species. Of the 1253 species included in quantitative analyses, most appeared to be rare – 85% were only found once. This indicates intra-regional endemism may be high, but undersampling is also likely. Species accumulation curves confirm that many additional species remain to be collected. There was high regional-scale spatial heterogeneity in species distribution patterns which appeared to be influenced by hydrographic patterns and feature-scale topography, and to a lesser extent by seabed type. Depth and oxygen concentration (correlated with depth) had most influence on distribution patterns of fauna, with assemblages identified from three depth-zones: 100–400 m (deep continental shelf and shelf edge), 400–700 m (upper continental slope) and >700 m (mid-continental slope). In the shallowest depth zone, there were north-south (latitudinal) patterns in invertebrate assemblages that appeared to be influenced by water mass distribution. Species overlap was higher in the south than the north, probably due to the Tasman Front forming a hydrographic connection between the southern parts of the Rise and the Ridge at shallower depths. At depths >700 m, the absence of a latitudinal pattern in assemblage structure was attributed to the continuity of Antarctic Intermediate Water in the study area. Differentiation of two assemblages in sled samples from the >700 m depth zone, as well as some patterns of diversity of large sessile fauna between sub-regions within the study area, suggested a relationship with bottom type but this was not fully analysed. While providing a major increase in scientific knowledge of marine biodiversity in deep waters of the Coral and Tasman Seas, these results also highlighted the paucity of biogeographical knowledge that exists for the area. Some science advances needed to inform national and international conservation plans currently under development are identified. They include taxonomic standardisation at a regional-scale (Australia, New Zealand and New Caledonia) for informative higher level taxa, and some additional surveys of selected areas and seabed features, including off northeastern Australia.

%B Deep Sea Research Part II: Topical Studies in Oceanography %I Deep Sea Research II (Lord Howe special issue) %V 58 %P 948 - 958 %8 01 Apr 2011 %U http://www.sciencedirect.com/science/article/pii/S0967064510003504 %N 7-8 %! Deep Sea Research Part II: Topical Studies in Oceanography %R 10.1016/j.dsr2.2010.10.050 %0 Journal Article %J ICES Journal of Marine Science %D 2011 %T Utility of a spatial habitat classification system as a surrogate of marine benthic community structure for the Australian margin %A Rachel Przeslawski %A Currie, D. R. %A Sorokin, S. J. %A Ward, T. M. %A Althaus, Franziska %A Williams, Alan %K benthic invertebrates %K continental margin %K interpolation %K seascapes %K Sponge %K Surrogacy %X This study tests whether a continental-scale classification of Australian benthic habitats (termed “seascapes”) and the interpolated environmental data from which they are derived are useful as abiotic surrogates of biodiversity at a local [tens of kilometres, Great Australian Bight (GAB)] and regional scale [hundreds of kilometres, Western Australian (WA) margin]. Benthic invertebrate community structure is moderately associated with specific seascapes in both the GAB (R = 0.418) and WA margin (excluding hard substrata, R = 0.375; all substrata, R = 0.313). Mud content, seafloor slope, and seafloor temperature are significantly correlated with invertebrate communities at both scales, with disturbance and primary production correlated with GAB communities. Seascapes are not consistently useful surrogates because the strength and significance of relationships between seascapes and community structure differs among seascapes, regions, and spatial scales. Nevertheless, a national system of seascapes is an appropriate surrogate for broad-scale benthic invertebrate community patterns when biological data are limited, provided the uncertainty is acknowledged and, where possible, an assessment made of each seascape's ability to differentiate biological communities. Further refinement of seascape derivations may include updated and additional environmental data (particularly for hard vs. soft substrata) and validation among biological datasets from a range of habitats and scales. %B ICES Journal of Marine Science %V 68 %P 1954 - 1962 %8 01 Sep 2011 %U http://icesjms.oxfordjournals.org/content/68/9/1954.abstract %N 9 %! ICES Journal of Marine Science %R 10.1093/icesjms/fsr106 %0 Journal Article %J Marine Ecology %D 2010 %T Are deep-sea demersal fish assemblages globally homogenous? Insights from seamounts %A Malcolm R Clark %A Althaus, Franziska %A Williams, Alan %A Niklitschek, Edwin %A Menezes, Gui M. %A Hareide, Nils-Roar %A Sutton, Philip %A ’Donnell, Ciaran %K Biogeography; deep-sea; fish assemblages; fish distribution; seamounts %X

Deep-sea fishes have been poorly sampled globally, and overall knowledge of demersal fish distributions and the drivers of community composition and diversity remain limited. Here, we used nine comparable datasets with species-level identification of fishes from research surveys around the world to test the hypothesis that deep-sea demersal fish assemblage composition on seamounts is consistent between major oceans. Two levels of analysis were undertaken: the first combined all presence-absence data from a seamount, while a second more detailed analysis included catch weight data based on a smaller number of seamounts. Overall, there was a consistent separation of seamounts by region based on the compositions of their fish assemblages. New Zealand and SE Australian seamounts have a very similar ichthyofauna, which differs substantially from seamounts in the eastern South Pacific Ocean off Chile. In the North Atlantic, Bear Seamount appears to be distinct from all others, while seamount fish assemblages off Ireland, the Azores, and Faraday Seamount have some affinities. The Tasman Sea and New Caledonian seamounts show strong intra-regional variation. On an ocean basin scale we therefore reject the hypothesis that the composition of deep-sea demersal fish fauna is homogeneous globally. However, regional patterns of both species composition and relative abundance show some similarities between widely separated geographical locations, especially where orange roughy is a dominant species. Salinity was the main environmental factor identified in a multivariate analysis of environmental covariate data. This is likely to be a result of salinity being a key characteristic defining both Antarctic Intermediate Water and North Atlantic Deep Water, the water masses found over most seamounts examined in this study, and which may explain similarities between deep-sea fish assemblages.

%B Marine Ecology %I Marine Ecology %V 31 %P 39 - 51 %8 01 Sep 2010 %U http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0485.2010.00384.x/abstract %R 10.1111/j.1439-0485.2010.00384.x %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 %D 2010 %T A test of the seamount oasis hypothesis: Seamounts support higher epibenthic megafaunal biomass than adjacent slopes. %A Rowden, Ashley A. %A Thomas A Schlacher %A Williams, Alan %A Malcolm R Clark %A Stewart, Robert %A Althaus, Franziska %A Bowden, David A. %A Consalvey, Mireille %A Robinson, Wayne %A Dowdney, Joanne %K Biomass %K epibenthic %K megafauna %K oasis hypothesis %K seamount %K slope %X Seamounts have often been viewed as specialized habitats that support unique communities; this notion has given rise to several hypotheses about how seamount ecosystems are structured. One, the ‘seamount oasis hypothesis’, predicts that invertebrates are more abundant, speciose and attain higher standing stocks on seamounts compared to other deep-sea habitats. Because this hypothesis has remained untested for biomass, we ask two questions: (i) Do seamounts support a higher benthic biomass than nearby slopes at corresponding depths? (ii) If they do, which particular taxa and trophic groups drive observed difference in biomass? Analysis of more than 5000 sea-floor images reveals that the mean biomass of epibenthic megafauna on 20 southwest Pacific seamounts was nearly four times greater than on the adjacent continental slope at comparable depths. This difference is largely attributable to the scleractinian coral Solenosmilia variabilis, whose mean biomass was 29 times higher on seamounts. In terms of trophic guilds, filter-feeders and filter-feeders/predators made up a significantly greater proportion of biomass on seamounts, whereas deposit feeders and those with mixed feeding modes dominated at slope habitats. Notwithstanding support for the seamount oasis hypothesis provided by this study, the hypothesis needs to be critically tested for seamounts in less productive regions, for seamounts with a greater proportion of soft substratum, and in other parts of the oceans where scleractinian corals are not prevalent. In this context, testing of seamount paradigms should be embedded in a broader ecological context that includes other margin habitats (e.g. canyons) and community metrics (e.g. diversity and body size). %B Marine Ecology %I Marine Ecology %V 31 %P 95 - 106 %8 01 Sep 2010 %U http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0485.2010.00369.x/abstract %R 10.1111/j.1439-0485.2010.00369.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 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