34. Parent identity influences adaptation potential of larval Acanthaster planci to ocean acidification and warming

Kate Sparks (1)*, Shawna Foo (2), Sven Uthicke (2), Maria Byrne (3), Miles Lamare (1)

1 Department of Marine Science, University of Otago, Dunedin, New Zealand
2 Schools of Medical and Biological Sciences, University of Sydney, Sydney, New South Wales, Australia.
3 Australian Institute of Marine Science, Townsville, Queensland, Australia

The crown-of-thorns sea star Acanthaster planci is a key predator on the Great Barrier Reef, and is thought to be responsible for up to 42% of coral cover loss worldwide. A. planci populations on the Great Barrier Reef follow a periodic ‘outbreak’ cycle during which large areas of coral reef can be decimated. These are thought to be primarily driven by an increase in food availability linked to warming water temperatures. The pattern of future Acanthaster outbreaks, and therefore the health of the Great Barrier Reef, are likely linked to how A.planci larvae cope with ocean acidification and warming.

This study used a quantitative genetic approach and a modified North Carolina II breeding design to examine the range of A.planci genotypes expressed in response to combined ocean warming and acidification. Interactions between genotype and environment were tested using a permutational multivariate ANOVA and Restricted Error Maximum Likelihood (REML) calculations of variance. Response ratios were calculated for offspring of each dam/sire pair across all treatments.

High temperature (32°C) and pCO2 (900ppm) both reduced normal development at 16-cell cleavage stage. At gastrulation, temperature had a significant negative effect on development, but pCO2 did not. Sire identity, and the interactions between temperature and pCO2, generated significant variation in offspring gastrulation success, however no equivalent interaction between maternal genotype and environment was seen. Response ratios indicated that most larvae exhibit highest gastrulation success in ‘present-day’ conditions. However, additive genetic variance (from sire x environment interactions) indicated that a sub-set of individuals develop best in both high temperatures and high pCO2.

The capacity to tolerate high temperatures and high pCO2 is a trait which is dependent on both genetic identity and environment. Larval tolerance to environmental changes and genotypic variation make A.planci an evolutionary ‘winner’ in a climate change scenario.

33. Lethal effects of increasing CO2 on dominant zooplankton in the Southern Ocean

Jake. R. Wallis (1)*, Kerrie, M. Swadling (2), So. Kawaguchi (2)

1 Institute for Marine and Antarctic Studies, Hobart, Tasmania, 7004, Australia,
2 Australian Antarctic Division, Kingston, Tasmania, 7050, Australia

Ocean acidification, caused by the absorption of CO2, is at the forefront of marine research due to the largely unknown implications for marine ecosystems. An increase in studies of the implications of ocean acidification are improving our knowledge of ways in which marine organisms will likely be impacted, including physiological stress, the diminished ability of some calcifying organisms to grow and changes to the base of planktonic food-webs. Information from the Southern Ocean is lacking for zooplankton other than krill and pteropods, making it difficult to investigate the potential implications of continued CO2 increases on lower trophic interactions. This is especially true for the fundamental copepod-fish food pathway that dominates north of the Southern Boundary of the Antarctic Circumpolar Current. Work undertaken during the Australian Antarctic Kerguelen-Axis voyage during the 2016 summer will examine the effects of increased CO2 on mortality of key zooplankton species. Lethal limits will be determined for species including the small, biomass dominant copepod Oithona similis and larger copepods Calanus propinquus, Rhincalanus gigas and Calanoides acutus, all of which undertake vertical migration and thus represent a strong link in the vertical flux of carbon from surface to deep-water. The pCO2 concentrations of ambient, 750, 1000, 1250, 1500, 2000 ppm will be used to determine lethal limits via incubations and thus provide a baseline that will inform further laboratory-based experiments with these species.

30. Lipid Use in the Lecithotrophic Larvae of Laternula elliptica under pH and Temperature Stress

Christine H. Bylenga (1), Vonda J. Cummings (2)*, Ken G. Ryan (1)

1 School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, New Zealand 6140
2 National Institute of Water and Atmospheric Research (NIWA), Private Bag 14901, Wellington, New Zealand 6021

Ocean change may impact larval development due to the increased energetic costs of acid-base regulation under ocean acidification and the maintenance of higher metabolic rates. This may strain energetic reserves, which are limited in lecithotrophic larvae, reducing larval response capacity or diverting energy from somatic growth or calcification.

The lecithotrophic larvae of the Antarctic bivalve, Laternula elliptica were raised under elevated temperature (-0.5, 0.5 and 1.5°C) and reduced pH conditions (pH 7.65). Primary lipid classes were identified and quantified in the larvae using a Thin Layer Chromatography/Flame Ionization Detection system. The use of lipids during development and under stress was determined by measuring the concentrations of different lipid classes and total lipids in newly fertilised and late stage larvae. Effects of temperature and pH conditions on D-larval metabolic rates were determined from oxygen consumption measurements.

The primary lipid classes in L. elliptica larvae were triacylglycerols and phospholipids, comprising over 85% of the total lipid content. Despite considerable depletion of both of these lipid classes during development, significant reserves remained for metamorphosis. However, lipid utilisation was not significantly different between treatments. In contrast, metabolic rates significantly increased in elevated temperature treatments, but were not affected at reduced pH.

Larvae of L. elliptica are well provisioned for development to the D-larval stage, with significant lipid reserves remaining for metamorphosis under end of century temperature and pH projections. The lack of significant treatment effects on lipid depletion was surprising given the increased metabolic rates. Furthermore, a companion study shows negative effects on larval growth, suggesting diversion of energetic resources away from larval development. However, increased energetic costs to maintaining acid-base balance may be met by sources other than lipids. Examination of the impacts of stressors on protein reserves is pending and those results will also be presented.

38. Effects of elevated sea water pCO2 on two species of euphausiids: Meganyctiphanes norvegica and Nyctiphanes couchii. Effect on survival, moulting, growth and food uptake

Anders Mangor-Jensen (1) ,Ingegjerd Opstad (1)*, Erik Sperfeld (3), Inger Semb Johansen (1), and Padmini Dalpadado (2)

1 Institute of Marine Research, Austevoll Research Station, 5392 Storebø, Norway
2 Institute of Marine Research, PO Box 1870, 5817 Bergen, Norway

3 Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB), Alte Fischerhütte 2, 16775 Stechlin

*Corresponding author: anders.mangor-jensen@imr.no

As a consequence of increased atmospheric concentration of CO2, more CO2 will diffuse into the global water bodies and shift the pH to a less basic state. This process is believed to be a result of anthropogenic emissions and referred to as ocean acidification. How different organisms cope in higher CO2 environments have been an important issue during the last decade. Euphausiids (krill) are ecological key species low in the food chain and represent a vast biomass predated on by fish and marine mammals. Krill are calcifiers, meaning that they deposit calcium carbonate to reinforce their exoskeleton. Effects of elevated pCO2 on these mechanisms were the aim of the present investigation.

Two species of North Sea krill (or more southerly distributed in the North Atlantic), Meganyctiphanes norvegica and Nyctipanes couchii, were collected from net hauls in Bjørnefjorden south of Bergen. The krill were sorted and stocked in 50 liter tanks were injured individuals were removed over a 7 days period. At the start of the experiment individual krill were transferred into 1 litre jars each supplied with flow through of experimental water. The jars were placed partially submerged in 50 litre tanks for temperature control.

The different water qualities were produced by adding highly enriched CO2 water to mixing tanks under control of feedback pumps. Total alkalinity and pH was registered at frequent intervals during the experimental period that lasted for 6 weeks. The target values were set to [CO2] = 1000 ppm (pH 7,4) and [CO2] = 1700 ppm (pH 7,6) in addition to untreated control water (pH= 7,9 [CO2]= 430 ppm). A total number of 24 krill were used at each pCO2 regime. During the experiment moults were collected from each jar to assess growth and molting frequencies. At termination a food intake experiment on individual basis were conducted, and the krill frozen in liquid nitrogen for determination of specific enzymes believed to participate in acid/base regulation. Findings of these ongoing experiments will be presented at the symposium.

19. Acclimation to environmental change: a long term record of a New Zealand brachiopod

Cross, E. L. (1,2)*, Peck, L. S. (1), Harper, E. M. (2)

1 British Antarctic Survey, Cambridge, CB3 0ET, UK
2 Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK

Since the Industrial Revolution, rising atmospheric CO2 levels have altered our oceans through warming and acidification. Current insights about species responses to environmental change are largely based on laboratory experiments and comparative field analyses, which provide useful insights into how natural populations may respond. However, these approaches do not tell us about how populations have changed in response to changing environments. Historical data from museum collections of shells provides an approach to test predictions from experimental and comparative analyses and, in conjunction with these methods, can be used to better predict the vulnerabilities of marine calcifiers to environmental change.

Shell characteristics were analysed from museum collections of the common New Zealand brachiopod Calloria inconspicua collected from the same sampling site in Stewart Island every decade since 1900 to the present day to determine any variation over time.

Over the last century, calcification index, total shell thickness, primary and secondary layer thickness, punctae (shell perforations) density and elemental composition of the shell have not changed. However, shell density has increased by 3.05% which can partially be explained by a decrease in punctae width by 8.26%.

This unique and valuable dataset indicates the resilience of possibly one of the most highly calcium carbonate dependent organisms to environmental change in their natural habitat over the last 110 years. The results also provide an insight into how this species might react to future change and its possible ability to adapt.

36. The Relationship Between Behavioural and Physiological Tolerance to Elevated CO2 in Coral Reef Fish

Taryn D. Laubenstein (1)*, Jodie L. Rummer (2), Philip L. Munday (2)

1 College of Marine and Environmental Sciences, James Cook University, Townsville, Qld, 4811, Australia
2 ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Qld, 4811, Australia

Reef fish exhibit both behavioural and physiological sensitivity to elevated CO2. However, individuals within populations demonstrate varying levels of sensitivity to these negative effects. Those individuals that are more tolerant provide hope for future populations to adapt to changing environmental conditions. Yet whether there is an interaction between behavioural and physiological tolerance, which may either constrain or facilitate adaptation, is unknown. We seek to understand the relationship between behavioural and physiological sensitivity to elevated CO2, and how it might be altered by elevated temperature.

Juvenile Acanthachromis polyacanthus will be reared from birth in one of four temperature x CO2 treatments: control, elevated temperature, elevated CO2, or elevated temperature and CO2. After 40 days, individuals from each treatment will be tested for their behavioural and physiological tolerance to elevated CO2. Behavioural tolerance will be measured as response to chemical alarm cue in a two-choice flume tunnel. Physiological tolerance will be measured as aerobic scope in a custom-built respirometer.

We predict that a tradeoff will exist between behavioural and physiological tolerance to CO2, where individuals with a high behavioural tolerance will have a low physiological tolerance, and vice versa. Furthermore, we predict that elevated temperature and CO2 together will have an additive or multiplicative effect on physiological tolerance but not behavioural tolerance.

Adaptation to high CO2 could be constrained if behavioural and physiological tolerance to elevated CO2 are negatively correlated at the level of the individual. Selection towards highly tolerant individuals will act orthogonally to the direction of the most genetic variation, and thus adaptation to high CO2 conditions will be limited. However, we predict that elevated temperature and CO2 conditions will lower physiological tolerance across the population. This would increase the importance of behavioural tolerance, and thus push future populations towards an increased behavioural tolerance.

15. The Effects of Natural CO2 Variability on Behavioural Sensitivity of Coral Reef Fish to Ocean Acidification

Michael D. Jarrold (1,2)* and Philip L. Munday (2)

1 College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland 4811, Australia.
2 ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4814, Australia.

Sensory performance and behavioural responses of coral reef fishes are impaired by CO2 levels projected to occur by the end of the century. However, coral reefs also experience daily CO2 fluctuations that can be greater than the projected increase in CO2 levels this century. Experiments to-date on behavioural effects of high CO2 have used steady-state treatments. It is therefore unknown how natural CO2 fluctuations will interact with rising mean CO2 levels to affect the behavioural sensitivity of coral reef fishes to ocean acidification.

We will rear juvenile damselfish, Acanthochromis polyacanthus, under a series of stable (450, 750, and 1050 µatm) and daily fluctuating CO2 treatments (450 ± 150 and 300 µatm, 750 ± 150 and 300 µatm and 1050 ± 300 and 600 µatm) for 10-14 days. After this period we will test their ability to recognise chemical alarm cues and escape responses; both important predator avoidance behaviours essential for daily survival. Testing these behaviours will enable us to determine how natural fluctuations in CO2 will affect olfactory (chemical alarm cue trials) and cognitive/locomotory (escape response trials) performances.

We predict that behavioural responses will not be impaired under fluctuating treatments, where CO2 levels drop below 600 µatm; the minimum level at which sensory and behavioral impairments have been observed. This prediction is based on evidence that it takes between 2-4 days of constant exposure to elevated CO2 levels for behavioural abnormalities to develop.

The results from our study will shed light on whether experiments incorporating natural fluctuations in CO2 are needed to more reliably predict the impacts of rising CO2 on shallow water marine organisms.

9. Impact of ocean acidification benthic foraminifera – Ammonia beccarii A. tepida and A. dentata – in captive condition

Kannan Gunasekaran (1)*, Deivasigamani Selvam (1) and Ayyappan Saravanakumar (1)

1 Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University Parangipettai – 608 502, Tamil Nadu, India.

*Corresponding author: bk.guna18@gmail.com

Ocean has absorbed the one third of CO2 from the atmosphere that has resulted in decreasing the ocean pH, a phenomenon known as ocean acidification. Ocean acidification affects many marine calcifying organisms, however, less is known about its impact on marine benthic foraminifera.

To analyse the impact of ocean acidification on shell morphology of different types of benthic foraminifera (Ammonia beccarii, A. tepida A. dentata), we cultured them during 20 weeks at various acidified seawater pCO2 conditions (400, 750, 970 and 1200 µatm).

The present study investigates the functional morphology of benthic foraminifer’s using Scanning Electron Microscopy images and it shows that the deformation of test ornamentation, shell damage and reduction in teeth structure of all the three species. The average numbers of teeth were slightly differed between the (40 ± 2.4) control and (16 ± 2.1) treatment. All foraminifers’ teeth structure shape changed into conical to round shape; test surface cracked and aperture area also affected during the higher treatment.

Foraminifera act important role food chain hence current investigation found that these foraminifera species are affected in CO2 induced ocean acidification experiments as a result foraminifera has vulnerable to ocean acidification.

Key words: Ammonia beccarii, A. tepida A. dentata shell size, reduction ornamentation, CO2, SEM

21. Potential for Adaptation of New Zealand Greenshell Mussels to a Higher CO2 World: Milestone 5.1 of CARIM (Coastal Acidification: Rate, Impacts & Management): An Integrated New Zealand Project

Camara M.D. (1), Hilton Z. (1), Ragg N.L.C. (1), Sewell M.A. (2), Cummings V.J. (3), and the CARIM Team (1-7)

1 The Cawthron Institute, 98 Halifax Street East, Nelson 7010, New Zealand
2 School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
3National Institute of Water and Atmospheric Research Ltd, Greta Point, Kilbirnie, Wellington, 6002, New Zealand
4 Department of Chemistry, University of Otago, Dunedin, New Zealand
5 NIWA, Department of Chemistry, University of Otago, Dunedin, New Zealand
6 NIWA, 10 Kyle Street, Riccarton, Christchurch 8011, New Zealand
7 Department of Marine Sciences, University of Otago, Dunedin, New Zealand

Greenshell mussels ( Perna canaliculus) are both an important endemic species in NZ coastal habitats, and also form the basis of an economically important aquaculture industry. As part of the New Zealand CARIM* project on rates, variability and impacts of coastal ocean acidification in New Zealand, we are examining the ability of Greenshell mussels to acclimate and adapt to lower seawater pH.

In order to examine the adaptive potential in Greenshell mussels we are taking advantage of a well-established selective breeding programme on Greenshell mussels run by the Cawthron Institute that contains established family lines based on individuals that have been sourced from around the country. We are screening these families for their ability to withstand low pH scenarios at the early embryo and larval stage.

Subsequently using a “polarise and characterise” approach, a small number of families which fall at the extremes of resilience and susceptibility to pH perturbation are being used as biological material to undertake detailed biological investigations to elucidate the underlying mechanisms conferring resilience. These investigations are being carried out using a range of tools from physiological energetics approaches to transcriptomics, proteomics and metabolomics.

We will present the results of the family screening programme and describe the approaches being used to identify underlying mechanisms of resilience.

*The CARIM (Coastal Acidification: Rate, Impacts & Management) programme is a new multi-disciplinary integrated project that aims to establish the rate and variability of pH change at nationally important coastal sites, the impacts of acidification on coastal ecosystems and iconic species (blackfoot abalone (Haliotis iris), Greenshell mussels and Snapper (Chrysophrys auratus)), and the potential of different approaches for managing these impacts.

20. Interactive effects of acidification and hypoxia and adaptive potential in red abalone (Haliotis rufescens)

Boles, S.E. (1, 2)*, Swezey, D. S. (1,3), Aquilino, K.M. (1), Catton, C. A. (4), Hill, T.M. (5), Gaylord, B. (7), Rogers-Bennett, L. (4,6), Sanford, E. (7), Whitehead, A. (2)

1 Bodega Marine Laboratory, University of California, Davis, 2099 Westside Road, Bodega Bay, CA, 94923, USA
2 Department of Environmental Toxicology, University of California, Davis, 1 Shields Ave, Davis, CA 95616, USA
3 The Cultured Abalone Farm, 9580 Dos Pueblos Canyon Road, Goleta, CA 93117, USA
4 California Department of Fish and Wildlife Marine Region, Bodega Marine Laboratory, 2099 Westside Road, Bodega Bay, CA, USA
5 Department of Geology and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA
6 Karen C. Drayer Wildlife Health Center and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA
7 Department of Evolution and Ecology and Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923, USA

Anthropogenic activities are changing multiple climate variables simultaneously, thereby presenting complex challenges to marine species. As increasing atmospheric CO2 acidifies the oceans, there may simultaneously be an increase in the frequency, intensity, and duration of hypoxic events worldwide. To avoid reduced fitness associated with rapidly changing conditions, marine organisms must either migrate, acclimate, or evolve. For evolution to rescue species, adaptive genetic variation must currently exist within the species geographic range. In this project, we seek to test whether historically divergent environments might have enriched populations for genetic variants that are prepared for future climate conditions. Coastal upwelling zones within the California Current System (CCS) naturally transport deep-ocean water that has low pH and low oxygen into nearshore habitats annually, such that populations of organisms inhabiting these regions of the coastline may be pre-adapted to future ocean conditions. We are developing red abalone (Haliotis rufescens) as a comparative physiological, developmental, and evolutionary model system for studying the combined impacts of ocean acidification (OA) and hypoxia. We are comparing populations that occupy habitats within upwelling regions of the CCS (and experience annual OA and hypoxia) to those that live outside of the upwelling region of the CCS (and do not experience annual OA and hypoxia). We are exposing multiple families of developing larvae to combined acidification and hypoxia to test for differences in survival, morphology, and molecular signalling pathways between populations, and to identify genetic variants that are favoured in future environments. Knowledge of population and genetic variation relevant to future environments will provide a valuable resource for conservation managers. Our discoveries will be shared with aquaculture facilities, who are partners in this research program and involved in a larger collaborative effort to maintain business sustainability and innovation during an era of rapid climate change.