Antarctic cushion star Odontaster validus larval performance is negatively impacted by long-term parental acclimation to elevated temperature.

Cross-generational responses, when the parents' environment influences offspring performance, may contribute to species resilience to climate change in rapidly warming regions such as coastal Antarctica. Adult Antarctic sea stars Odontaster validus were conditioned in the laboratory to two temperature treatments (ambient, 0 °C and warming, +3 °C) for two years, and their gametes were used to generate larval offspring. The response of their larvae to five temperatures (0 °C, 1 °C, 2 °C, 3 °C, and 4 °C) was examined over 145 days.

Unlocking Antarctic molecular time-capsules - Recovering historical environmental DNA from museum-preserved sponges.

Marine sponges have recently emerged as efficient natural environmental DNA (eDNA) samplers. The ability of sponges to accumulate eDNA provides an exciting opportunity to reconstruct contemporary communities and ecosystems with high temporal and spatial precision. However, the use of historical eDNA, trapped within the vast number of specimens stored in scientific collections, opens up the opportunity to begin to reconstruct the communities and ecosystems of the past.

Streamlining large-scale oceanic biomonitoring using passive eDNA samplers integrated into vessel's continuous pump underway seawater systems.

Passive samplers are enabling the scaling of environmental DNA (eDNA) biomonitoring in our oceans, by circumventing the time-consuming process of water filtration. Designing a novel passive sampler that does not require extensive sample handling time and can be connected to ocean-going vessels without impeding normal underway activities has potential to rapidly upscale global biomonitoring efforts onboard the world's oceanic fleet. Here, we demonstrate the utility of an artificial sponge sampler connected to the continuous pump underway seawater system as a means to enable oceanic biomonitoring.

Kelp holdfast microclimates buffer invertebrate inhabitants from extreme temperatures.

Climate change is altering environmental conditions, with microclimates providing small-scale refuges within otherwise challenging environments. Durvillaea (southern bull kelp; rimurapa) is a genus of large intertidal fucoid algae, and some species harbour diverse invertebrate communities in their holdfasts. We hypothesised that animal-excavated Durvillaea holdfasts provide a thermal refuge for epibiont species, and tested this hypothesis using the exemplar species D.

The added costs of winter ocean warming for metabolism, arm regeneration and survival in the brittle star Ophionereis schayeri.

As the climate continues to change, it is not just the magnitude of these changes that is important - equally critical is the timing of these events. Conditions that may be well tolerated at one time can become detrimental if experienced at another, as a result of seasonal acclimation. Temperature is the most critical variable as it affects most aspects of an organism's physiology.

Assessing the utility of marine filter feeders for environmental DNA (eDNA) biodiversity monitoring.

Aquatic environmental DNA (eDNA) surveys are transforming how marine ecosystems are monitored. The time-consuming preprocessing step of active filtration, however, remains a bottleneck. Hence, new approaches that eliminate the need for active filtration are required.

Developing an effective marine eDNA monitoring: eDNA detection at pre-outbreak densities of corallivorous seastar (Acanthaster cf. solaris).

Outbreaks of the corallivorous Crown-of-Thorns Seastar (CoTS) Acanthaster cf. solaris contribute significantly to coral reef loss. Control of outbreaks is hampered because standard monitoring techniques do not detect outbreaks at early (low density) stages, thus preventing early intervention.

Staying in place and moving in space: Contrasting larval thermal sensitivity explains distributional changes of sympatric sea urchin species to habitat warming.

For marine ectotherms, larval success, planktonic larval duration and dispersal trajectories are strongly influenced by temperature, and therefore, ocean warming and heatwaves have profound impacts on these sensitive stages. Warming, through increased poleward flow in regions with western boundary currents, such as the East Australia Current (EAC), provides opportunities for range extension as propagules track preferred conditions. Two sea urchin species, Centrostephanus rodgersii and Heliocidaris tuberculata, sympatric in the EAC warming hotspot, exhibit contrasting responses to warming.

Microplastic ingestion induces asymmetry and oxidative stress in larvae of the sea urchin Pseudechinus huttoni.

Determining the effects of microplastic (MP) ingestion by marine organisms, especially during the sensitive larval stages, is an important step in understanding wider ecosystem responses. We investigated the ingestion, retention (1-5 μm), and short-term exposure effects (1-4 μm) of spherical MPs by larvae of the sea urchin Pseudechinus huttoni. Larvae ingested MPs in a dose-dependent manner and successfully egested particles after a short retention period.

Cross-generational response of a tropical sea urchin to global change and a selection event in a 43-month mesocosm study.

Long-term experimental investigations of transgenerational plasticity (TGP) and transgenerational acclimatization to global change are sparse in marine invertebrates. Here, we test the effect of ocean warming and acidification over a 25-month period of Echinometra sp. A sea urchins whose parents were acclimatized at ambient or one of two near-future (projected mid and end of the 21st century) climate scenarios for 18 months.

Reduced seawater pH alters marine biofilms with impacts for marine polychaete larval settlement.

Ocean acidification (OA) can negatively affect early-life stages of marine organisms, with the key processes of larval settlement and metamorphosis potentially vulnerable to reduced seawater pH. Settlement success depends strongly on suitable substrates and environmental cues, with marine biofilms as key settlement inducers for a range of marine invertebrate larvae. This study experimentally investigated (1) how seawater pH determines growth and community composition of marine biofilms, and (2) whether marine biofilms developed under different pH conditions can alter settlement success in the New Zealand serpulid polychaete Galeolaria hystrix.

Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean.

Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth-ocean-atmosphere dynamic exchange of elements. The ratios' dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally.

Sea urchin larvae show resilience to ocean acidification at the time of settlement and metamorphosis.

Extensive research has shown that the early life stages of marine organisms are sensitive to ocean acidification (OA). Less is known, however, on whether larval settlement and metamorphosis may be affected, or by which mechanisms. These are key processes in the life cycle of most marine benthic organisms, since they mark the transition between the free swimming larval stage to benthic life.

Ocean acidification affects microbial community and invertebrate settlement on biofilms.

Increased atmospheric CO is driving ocean acidification (OA), and potential changes in marine ecosystems. Research shows that both planktonic and benthic communities are affected, but how these changes are linked remains unresolved. Here we show experimentally that decreasing seawater pH (from pH 8.

Little evidence of adaptation potential to ocean acidification in sea urchins living in "Future Ocean" conditions at a CO vent.

Ocean acidification (OA) can be detrimental to calcifying marine organisms, with stunting of invertebrate larval development one of the most consistent responses. Effects are usually measured by short-term, within-generation exposure, an approach that does not consider the potential for adaptation. We examined the genetic response to OA of larvae of the tropical sea urchin sp.

Beyond Biodiversity: Can Environmental DNA (eDNA) Cut It as a Population Genetics Tool?

Population genetic data underpin many studies of behavioral, ecological, and evolutionary processes in wild populations and contribute to effective conservation management. However, collecting genetic samples can be challenging when working with endangered, invasive, or cryptic species. Environmental DNA (eDNA) offers a way to sample genetic material non-invasively without requiring visual observation.

Species-level biodiversity assessment using marine environmental DNA metabarcoding requires protocol optimization and standardization.

DNA extraction from environmental samples (environmental DNA; eDNA) for metabarcoding-based biodiversity studies is gaining popularity as a noninvasive, time-efficient, and cost-effective monitoring tool. The potential benefits are promising for marine conservation, as the marine biome is frequently under-surveyed due to its inaccessibility and the consequent high costs involved. With increasing numbers of eDNA-related publications have come a wide array of capture and extraction methods.

Environmental DNA (eDNA) metabarcoding reveals strong discrimination among diverse marine habitats connected by water movement.

While in recent years environmental DNA (eDNA) metabarcoding surveys have shown great promise as an alternative monitoring method, the integration into existing marine monitoring programs may be confounded by the dispersal of the eDNA signal. Currents and tidal influences could transport eDNA over great distances, inducing false-positive species detection, leading to inaccurate biodiversity assessments and, ultimately, mismanagement of marine environments. In this study, we determined the ability of eDNA metabarcoding surveys to distinguish localized signals obtained from four marine habitats within a small spatial scale (<5 km) subject to significant tidal and along-shore water flow.

Hematological Analysis of the Ascidian Botrylloides leachii (Savigny, 1816) During Whole-Body Regeneration.

Whole-body regeneration (WBR)-the formation of an entire adult from only a small fragment of its own tissue-is extremely rare among chordates. Exceptionally, in the colonial ascidian Botrylloides leachii (Savigny, 1816) a fully functional adult is formed from their common vascular system after ablation of all adults from the colony in just 10 d, thanks to their high blastogenetic potential. While previous studies have identified key genetic markers and morphological changes, no study has yet focused on the hematological aspects of regeneration despite the major involvement of the remaining vascular system and the contained hemocytes in this process.

Maternal antioxidant provisioning mitigates pollutant-induced oxidative damage in embryos of the temperate sea urchin Evechinus chloroticus.

One mechanism of pollution resistance in marine populations is through transgenerational plasticity, whereby offspring capacity to resist pollution reflects parental exposure history. Our study aimed to establish correlations between oxidative stress biomarkers and key reproductive fitness parameters in the temperate sea urchin Evechinus chloroticus following exposure to dietary polycyclic aromatic hydrocarbons (PAHs). PAH-exposed adults exhibited total gonad tissue concentrations of PAHs in excess of 4 and 5 times baseline levels, for females and males respectively.

In situ developmental responses of tropical sea urchin larvae to ocean acidification conditions at naturally elevated pCO2 vent sites.

Laboratory experiments suggest that calcifying developmental stages of marine invertebrates may be the most ocean acidification (OA)-sensitive life-history stage and represent a life-history bottleneck. To better extrapolate laboratory findings to future OA conditions, developmental responses in sea urchin embryos/larvae were compared under ecologically relevant in situ exposures on vent-elevated pCO and ambient pCO coral reefs in Papua New Guinea. Echinometra embryos/larvae were reared in meshed chambers moored in arrays on either venting reefs or adjacent non-vent reefs.

Ocean acidification has little effect on developmental thermal windows of echinoderms from Antarctica to the tropics.

As the ocean warms, thermal tolerance of developmental stages may be a key driver of changes in the geographical distributions and abundance of marine invertebrates. Additional stressors such as ocean acidification may influence developmental thermal windows and are therefore important considerations for predicting distributions of species under climate change scenarios. The effects of reduced seawater pH on the thermal windows of fertilization, embryology and larval morphology were examined using five echinoderm species: two polar (Sterechinus neumayeri and Odontaster validus), two temperate (Fellaster zelandiae and Patiriella regularis) and one tropical (Arachnoides placenta).

Dietary pollutants induce oxidative stress, altering maternal antioxidant provisioning and reproductive output in the temperate sea urchin Evechinus chloroticus.

Evidence is growing to suggest that the capacity to withstand oxidative stress may play an important role in shaping life-history trade-offs, although little is known on the relationship in broadcast spawning marine invertebrates. In this group, variation in gamete quantity and quality are important drivers of offspring survival and successful recruitment. Therefore the provisioning of eggs with antioxidants may be an important driver of life history strategies because they play a critical role in preventing damage from reactive oxygen species to macromolecules.

A comparative study of vitellogenesis in Echinodermata: Lessons from the sea star.

The provision of yolk precursor proteins to the oviparous egg is crucial for normal embryo development. In Echinodermata, a transferrin-like yolk component termed major yolk protein (MYP) is a major precursor protein in Echinoidea and Holothuroidea. In contrast, in Asteroidea a single vitellogenin (Vtg) was recently identified, but its role as primary yolk protein remains unclear.