Scope for latitudinal extension of reef corals is species specific

In their recent paper, Muir et al. (Science, 2015, 348, 1135-1138) demonstrate that the maximum depths of staghorn coral assemblages are shallower at higher latitudes, a trend that correlates with winter light levels. Based on these findings, the authors hypothesize that light availability limits the current latitudinal extent of the group and will constrain future range expansion. Here we reanalyze their data and show that depth-latitude relationships vary substantially among species, and that most species show either no significant pattern or the opposite pattern. In so doing, our reanalysis highlights a common misinterpretation of mixed-effects models: the fallacy of the average. Our findings are also consistent with fossil and contemporary observations of coral range-shifts. The factors that limit the current range extent of corals remain elusive, but they are likely speciesspecific and will require much further research to elucidate

Allometric growth in reef-building corals

Funding: ARC Centre of Excellence for Coral Reef Studies and the Australian Research Council for fellowship and research support; Scottish Funding Council (MASTS, grant reference HR09011) and the ERC project bioTIME.Predicting demographic rates is a critical part of forecasting the future of ecosystems under global change. Here, we test if growth rates can be predicted from morphological traits for a highly diverse group of colonial symbiotic organisms: scleractinian corals. We ask whether growth is isometric or allometric among corals, and whether most variation in coral growth rates occurs at the level of the species or morphological group. We estimate growth as change in planar area for 11 species, across five morphological groups and over 5 years. We show that coral growth rates are best predicted from colony size and morphology rather than species. Coral size follows a power scaling law with a constant exponent of 0.91. Despite being colonial organisms, corals have consistent allometric scaling in growth. This consistency simplifies the task of projecting community responses to disturbance and climate change.PostprintPeer reviewe

A test of adaptive strategy theory using fifteen years of change in coral abundance

Universal Adaptive Strategy Theory aims to predict how taxa and assemblages respond to disturbances on the basis of adaptive strategy group (ASG) membership. Here, we test such predictions using the adaptive strategy scheme for reef-building corals developed by Darling et al. (Ecol Lett 15:1378–1386, 2012) and a long-term dataset of coral assemblage structure from inshore reefs on the central Great Barrier Reef. Several disturbances including mass bleaching and tropical storms were recorded in this 15-year interval from 1998 to 2013. ASG membership did not predict how a given taxon responded to disturbance. In fact, all ASGs were on average equally affected by bleaching and a period of multiple disturbances. Furthermore, there were no consistent winners at these sites in response to the 1998 bleaching in contrast to previous work suggesting clear hierarchies in susceptibility to bleaching. In conclusion, while further efforts to re-evaluate the utility of ASGs for reef corals should be encouraged our results and a re-examination of the literature suggests that direct trait-based approaches might prove more useful when exploring how corals respond to disturbance

Comment on “Chemically Mediated Behavior of Recruiting Corals and Fishes: A Tipping Point That May Limit Reef Recovery”

Dixson et al. (2014) report that coral larvae navigate towards chemical cues associated with healthy reefs and avoid cues from degraded reefs. However, the swimming capabilities of coral larvae and well-established patterns of recruitment and reef hydrodynamics indicate that coral larvae will not be able to use these cues to recruit to healthy reefs. Perfuming degraded reefs, as suggested by Dixson et al (2014), will not enhance recovery rather it will distract from the difficult task of reducing fishing effort and improving water quality

Partitioning colony size variation into growth and partial mortality

We thank the Australian Research Council for fellowship and research support. M.A.D. is funded by a Leverhulme Fellowship and by the John Templeton Foundation grant no. 60501.Body size is a trait that broadly influences the demography and ecology of organisms. In unitary organisms, body size tends to increase with age. In modular organisms, body size can either increase or decrease with age, with size changes being the net difference between modules added through growth and modules lost through partial mortality. Rates of colony extension are independent of body size, but net growth is allometric, suggesting a significant role of size-dependent mortality. In this study, we develop a generalizable model of partitioned growth and partial mortality and apply it to data from 11 species of reef-building coral. We show that corals generally grow at constant radial increments that are size independent, and that partial mortality acts more strongly on small colonies. We also show a clear life-history trade-off between growth and partial mortality that is governed by growth form. This decomposition of net growth can provide mechanistic insights into the relative demographic effects of the intrinsic factors (e.g. acquisition of food and life-history strategy), which tend to affect growth, and extrinsic factors (e.g. physical damage, and predation), which tend to affect mortality.PostprintPostprintPeer reviewe

Net effects of life-history traits explain persistent differences in abundance among similar species

JSM and MM were supported by the National Science Foundation (NSF)1948946. MD is supported by the Warman Foundation, the Leverhulme Centre for Anthropocene Biodiversity (RC-2018-021) and NSF-NERC grant NE/V009338/1. MM is supported by a Leverhulme Trust Early Career Fellowship (ECF-2021-512).Life-history traits are promising tools to predict species commonness and rarity because they influence a population's fitness in a given environment. Yet, species with similar traits can have vastly different abundances, challenging the prospect of robust trait-based predictions. Using long-term demographic monitoring, we show that coral populations with similar morphological and life-history traits show persistent (decade-long) differences in abundance. Morphological groups predicted species positions along two, well-known life-history axes (the fast-slow continuum and size-specific fecundity). However, integral projection models revealed that density-independent population growth (λ) was more variable within morphological groups, and was consistently higher in dominant species relative to rare species. Within-group λ differences projected large abundance differences among similar species in short timeframes, and were generated by small but compounding variation in growth, survival, and reproduction. Our study shows that easily-measured morphological traits predict demographic strategies, yet small life-history differences can accumulate into large differences in λ and abundance among similar species. Quantifying the net effects of multiple traits on population dynamics is therefore essential to anticipate species commonness and rarity.Publisher PDFPeer reviewe

Cumulative effects of cyclones and bleaching on coral cover and species richness at Lizard Island

Funding was provided by the Australian Council Centre of Excellence for Coral Reef Studies (COE140100020) and the John Templeton Foundation (M.D., J.S.M. grant #60501 'Putting the Extended Evolutionary Synthesis to the Test’).Coral reefs are being subjected to an increase in the frequency and intensity of disturbance, such as bleaching and cyclones, and it is important to document the effects of such disturbance on reef coral assemblages. Between March 2014 and May 2017, the reefs of Lizard Island in the northern section of the Great Barrier Reef were affected by 4 consecutive disturbances: severe tropical cyclones Ita and Nathan in 2014 and 2015, and mass bleaching events in 2016 and 2017. Loss of coral cover following the cyclones was patchy and dependent on the direction of the waves generated. In contrast, loss of cover following bleaching was much more uniform. Overall, coral cover declined 5-fold from 36% pre-cyclone Ita to 7% post-bleaching in 2017, while mean species richness dropped from 10 to 4 species per transect. The spatial scale and magnitude of the loss of coral cover in the region suggests that it will be many years before these reefs recover.PostprintPeer reviewe

Selecting coral species for reef restoration

1. Humans have long sought to restore species but little attention has been directed at how to best select a subset of foundation species for maintaining rich assemblages that support ecosystems, like coral reefs and rainforests, which are increasingly threatened by environmental change. 2. We propose a two-part hedging approach that selects optimized sets of species for restoration. The first part acknowledges that biodiversity supports ecosystem functions and services, and so it ensures precaution against loss by allocating an even spread of phenotypic traits. The second part maximizes species and ecosystem persistence by weighting species based on characteristics that are known to improve ecological persistence—for example abundance, species range and tolerance to environmental change. 3. Using existing phenotypic-trait and ecological data for reef building corals, we identified sets of ecologically persistent species by examining marginal returns in occupancy of phenotypic trait space. We compared optimal sets of species with those from the world's southern-most coral reef, which naturally harbours low coral diversity, to show these occupy much of the trait space. Comparison with an existing coral restoration program indicated that current corals used for restoration only cover part of the desired trait space and programs may be improved by including species with different traits. 4. Synthesis and applications. While there are many possible criteria for selecting species for restoration, the approach proposed here addresses the need to insure against unpredictable losses of ecosystem services by focusing on a wide range of phenotypic traits and ecological characteristics. Furthermore, the flexibility of the approach enables the functional goals of restoration to vary depending on environmental context, stakeholder values, and the spatial and temporal scales at which meaningful impacts can be achieved

Open Science principles for accelerating trait-based science across the Tree of Life.

Synthesizing trait observations and knowledge across the Tree of Life remains a grand challenge for biodiversity science. Species traits are widely used in ecological and evolutionary science, and new data and methods have proliferated rapidly. Yet accessing and integrating disparate data sources remains a considerable challenge, slowing progress toward a global synthesis to integrate trait data across organisms. Trait science needs a vision for achieving global integration across all organisms. Here, we outline how the adoption of key Open Science principles-open data, open source and open methods-is transforming trait science, increasing transparency, democratizing access and accelerating global synthesis. To enhance widespread adoption of these principles, we introduce the Open Traits Network (OTN), a global, decentralized community welcoming all researchers and institutions pursuing the collaborative goal of standardizing and integrating trait data across organisms. We demonstrate how adherence to Open Science principles is key to the OTN community and outline five activities that can accelerate the synthesis of trait data across the Tree of Life, thereby facilitating rapid advances to address scientific inquiries and environmental issues. Lessons learned along the path to a global synthesis of trait data will provide a framework for addressing similarly complex data science and informatics challenges

Crop Updates 1999 - Oilseeds

This article contains eighteen papers INTRODUCTION, Paul Carmody, Agriculture Western Australia PLENARY SESSION Transgenic canola in Western Australia: Outlook and challenges, Phil Salisbury, University of Melbourne Farming system issues for herbicide tolerant canola, Rick Madin, Rick Madin and Associates, David Bowran, Agriculture Western Australia Beating blackleg in 1999, Martin Barbetti, Ravjit Khangura, Paul Carmody, Graham Walton, Agriculture Western Australia The Mustard Industry in Australia – Opportunities for a new oilseed, Phil Parker, NSW Agriculture Management of blackleg with fungicides, Ravjit Khangura and Martin Barbetti, Agriculture Western Australia Effect of aphid feeding damage on canola yields in 1998, Francoise Berlandier and Linnet Cartwright, Agriculture Western Australia Post-anthesis duration and rainfall affect oil content of canola, Ping Si, University of West Australia, Graham Walton, Agriculture Western Australia, Nick Galwey and David Turner, University of West Australia Canola responded to high rates of fertiliser in 1998, Wayne Pluske, CSBP Impact of agronomic practices on canola quality, Graham Walton, Agriculture Western Australia Survey reveals widespread infection with two virus diseases in Western Australian canola crops, Roger Jones and Brenda Coutts, Agriculture Western Australia Calculating canola yields and oil contents as a function of soil and fertiliser nitrogen supply, Bill Bowden and Isabel Arevalo-Vigne, Agriculture Western Australia Canola benchmarks 1997/98 – Central Eastern District, Jeff Russell, Agriculture Western Australia Seeding rate affects the yield and some architectural features of canola, Syed H. Zaheer, Nick W. Galwey and David Turner, University of Western Australia Foliar applied fungicides for blackleg, Andrew Simon and Art Diggle, Agriculture Western Australia Farm based demonstration 1998 canola N – Wheel evaluation, Jeff Russell, Agriculture Western Australia Effect of sowing date on seed yield of canola, Dave Eksteen, Agriculture Western Australia Investigating water use of summer crops on the South Coast of Western Australia, Arjen Ryder, Agriculture Western Australia, Bill Crabtree, Western Australia No Till Farming Association, Serena Wyatt, Catchment Landcare Coordinator, Wellstead, Jim Baily, Subasio Downs, Wellstead INTRODUCTION, Paul Carmody, Agriculture Western Australia PLENARY SESSION Transgenic canola in Western Australia: Outlook and challenges, Phil Salisbury, University of Melbourne Farming system issues for herbicide tolerant canola, Rick Madin, Rick Madin and Associates, David Bowran, Agriculture Western Australia Beating blackleg in 1999, Martin Barbetti, Ravjit Khangura, Paul Carmody, Graham Walton, Agriculture Western Australia The Mustard Industry in Australia – Opportunities for a new oilseed, Phil Parker, NSW Agriculture Management of blackleg with fungicides, Ravjit Khangura and Martin Barbetti, Agriculture Western Australia Effect of aphid feeding damage on canola yields in 1998, Francoise Berlandier and Linnet Cartwright, Agriculture Western Australia Post-anthesis duration and rainfall affect oil content of canola, Ping Si, University of West Australia, Graham Walton, Agriculture Western Australia, Nick Galwey and David Turner, University of West Australia Canola responded to high rates of fertiliser in 1998, Wayne Pluske, CSBP Impact of agronomic practices on canola quality, Graham Walton, Agriculture Western Australia Survey reveals widespread infection with two virus diseases in Western Australian canola crops, Roger Jones and Brenda Coutts, Agriculture Western Australia Calculating canola yields and oil contents as a function of soil and fertiliser nitrogen supply, Bill Bowden and Isabel Arevalo-Vigne, Agriculture Western Australia Canola benchmarks 1997/98 – Central Eastern District, Jeff Russell, Agriculture Western Australi