Vulnerability of Temperate Mesophotic Ecosystems (TMEs) to environmental impacts: Rapid ecosystem changes at Lough Hyne Marine Nature Reserve, Ireland.

Temperate Mesophotic Ecosystems (TMEs) are stable habitats, usually dominated by slow-growing, long-lived sessile invertebrates and sciaphilous algae. Organisms inhabiting TMEs can form complex three-dimensional structures and support many commercially important species. However, TMEs have been poorly studied, with little known about their vulnerability to environmental impacts.

Scaling of heart rate with breathing frequency and body mass in cetaceans.

Plasticity in the cardiac function of a marine mammal facilitates rapid adjustments to the contrasting metabolic demands of breathing at the surface and diving during an extended apnea. By matching their heart rate () to their immediate physiological needs, a marine mammal can improve its metabolic efficiency and maximize the proportion of time spent underwater. Respiratory sinus arrhythmia (RSA) is a known modulation of that is driven by respiration and has been suggested to increase cardiorespiratory efficiency.

Evidence of egg-laying grounds for critically endangered flapper skate (Dipturus intermedius) off Orkney, UK.

Essential fish habitats (EFHs) are critical for fish life-history events, including spawning, breeding, feeding or growth. This study provides evidence of EFHs for the critically endangered flapper skate (Dipturus intermedius) in the waters around the Orkney Isles, Scotland, based on citizen-science observation data. The habitats of potential egg-laying sites were parametrised as >20 m depth, with boulders or exposed bedrock, in moderate current flow (0.

Seagrass-driven changes in carbonate chemistry enhance oyster shell growth.

Quantifying the strength of non-trophic interactions exerted by foundation species is critical to understanding how natural communities respond to environmental stress. In the case of ocean acidification (OA), submerged marine macrophytes, such as seagrasses, may create local areas of elevated pH due to their capacity to sequester dissolved inorganic carbon through photosynthesis. However, although seagrasses may increase seawater pH during the day, they can also decrease pH at night due to respiration.

Maternal effects and fitness consequences of individual variation in bottlenose dolphins' ecological niche.

The niche describes the ecological and social environment that an organism lives in, as well as the behavioural tactics used to interact with its environment. A species niche is key to both ecological and evolutionary processes, including speciation, and has therefore been a central focus in ecology. Recent evidence, however, points to considerable individual variation in a species' or population's niche use, although how this variation evolves or is maintained remains unclear.

The stress and strain of life - how differences in the mechanical properties and cellular composition enable the kelp Laminaria digitata to thrive in different hydrodynamic environments.

Sessile organisms such as macroalgae located in the intertidal and shallow subtidal zones are subject to a hydrodynamically diverse environment, controlling the variation of intraspecific morphology and distribution. Kelp forests experience both waves and/or currents, yet, how kelp blade material mechanically differs between these various hydrodynamic environments and what drives the variation in strength and extensibility are not fully understood. Here, the mechanical properties, cellular composition and blade tissue thickness of the meristematic region and distal tips of the kelp Laminaria digitata blades were quantified and compared between seasons and among three hydrodynamic environments: wave dominated, current dominated and a benign hydrodynamic environment.

Conditioned Variation in Heart Rate During Static Breath-Holds in the Bottlenose Dolphin ().

Previous reports suggested the existence of direct somatic motor control over heart rate ( ) responses during diving in some marine mammals, as the result of a cognitive and/or learning process rather than being a reflexive response. This would be beneficial for O storage management, but would also allow ventilation-perfusion matching for selective gas exchange, where O and CO can be exchanged with minimal exchange of N. Such a mechanism explains how air breathing marine vertebrates avoid diving related gas bubble formation during repeated dives, and how stress could interrupt this mechanism and cause excessive N exchange.

Respiratory sinus arrhythmia and submersion bradycardia in bottlenose dolphins ().

Among the many factors that influence the cardiovascular adjustments of marine mammals is the act of respiration at the surface, which facilitates rapid gas exchange and tissue re-perfusion between dives. We measured heart rate () in six adult male bottlenose dolphins () spontaneously breathing at the surface to quantify the relationship between respiration and , and compared this with during submerged breath-holds. We found that dolphins exhibit a pronounced respiratory sinus arrhythmia (RSA) during surface breathing, resulting in a rapid increase in after a breath followed by a gradual decrease over the following 15-20 s to a steady that is maintained until the following breath.

Long-term washover fan accretion on a transgressive barrier island challenges the assumption that paleotempestites represent individual tropical cyclones.

Barrier island overwash occurs when the elevation of wave runup exceeds the dune crest and induces landward transport of sediment across a barrier island and deposition of a washover deposit. Washover deposition is generally attributed to major storms, is important for the maintenance of barrier island resilience to sea-level rise and is used to extend hurricane records beyond historical accounts by reconstructing the frequency and extent of washover deposits preserved in the sedimentary record. Here, we present a high-fidelity 3-year record of washover evolution and overwash at a transgressive barrier island site.

High Abundances of Microplastic Pollution in Deep-Sea Sediments: Evidence from Antarctica and the Southern Ocean.

Plastic pollution in Antarctica and the Southern Ocean has been recorded in scientific literature since the 1980s; however, the presence of microplastic particles (<5 mm) is less understood. Here, we aimed to determine whether microplastic accumulation would vary among Antarctic and Southern Ocean regions through studying 30 deep-sea sediment cores. Additionally, we aimed to highlight whether microplastic accumulation was related to sample depth or the sediment characteristics within each core.

begins exoskeleton mineralization within 48 hours of metamorphosis.

Barnacles are ancient arthropods that, as adults, are surrounded by a hard, mineralized, outer shell that the organism produces for protection. While extensive research has been conducted on the glue-like cement that barnacles use to adhere to surfaces, less is known about the barnacle exoskeleton, especially the process by which the barnacle exoskeleton is formed. Here, we present data exploring the changes that occur as the barnacle cyprid undergoes metamorphosis to become a sessile juvenile with a mineralized exoskeleton.

Extreme diving in mammals: first estimates of behavioural aerobic dive limits in Cuvier's beaked whales.

We analysed 3680 dives from 23 satellite-linked tags deployed on Cuvier's beaked whales to assess the relationship between long duration dives and inter-deep dive intervals and to estimate aerobic dive limit (ADL). The median duration of presumed foraging dives was 59 min and 5% of dives exceeded 77.7 min.

Environmental stability impacts the differential sensitivity of marine microbiomes to increases in temperature and acidity.

Ambient conditions shape microbiome responses to both short- and long-duration environment changes through processes including physiological acclimation, compositional shifts, and evolution. Thus, we predict that microbial communities inhabiting locations with larger diel, episodic, and annual variability in temperature and pH should be less sensitive to shifts in these climate-change factors. To test this hypothesis, we compared responses of surface ocean microbes from more variable (nearshore) and more constant (offshore) sites to short-term factorial warming (+3 °C) and/or acidification (pH -0.

Lunge filter feeding biomechanics constrain rorqual foraging ecology across scale.

Fundamental scaling relationships influence the physiology of vital rates, which in turn shape the ecology and evolution of organisms. For diving mammals, benefits conferred by large body size include reduced transport costs and enhanced breath-holding capacity, thereby increasing overall foraging efficiency. Rorqual whales feed by engulfing a large mass of prey-laden water at high speed and filtering it through baleen plates.

Cardiorespiratory coupling in cetaceans; a physiological strategy to improve gas exchange?

In the current study we used transthoracic echocardiography to measure stroke volume (SV), heart rate () and cardiac output (CO) in adult bottlenose dolphins (), a male beluga whale calf [, body mass () range: 151-175 kg] and an adult female false killer whale (, estimated : 500-550 kg) housed in managed care. We also recorded continuous electrocardiogram (ECG) in the beluga whale, bottlenose dolphin, false killer whale, killer whale () and pilot whale () to evaluate cardiorespiratory coupling while breathing spontaneously under voluntary control. The results show that cetaceans have a strong respiratory sinus arrythmia (RSA), during which both and SV vary within the interbreath interval, making average values dependent on the breathing frequency ().

Exploring movement patterns and changing distributions of baleen whales in the western North Atlantic using a decade of passive acoustic data.

Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate-driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis).

Strengthen causal models for better conservation outcomes for human well-being.

Background: Understanding how the conservation of nature can lead to improvement in human conditions is a research area with significant growth and attention. Progress towards effective conservation requires understanding mechanisms for achieving impact within complex social-ecological systems. Causal models are useful tools for defining plausible pathways from conservation actions to impacts on nature and people.

Trinomial decompression sickness model using full, marginal, and non-event outcomes.

Decompression sickness (DCS) is a condition associated with reductions in ambient pressure during underwater diving and altitude exposure. Determining the risk of DCS from a dive exposure remains an active area of research, with the goal of developing safe decompression schedules to mitigate the occurrence of DCS. This work develops a probabilistic model for the trinomial outcome of full, marginal, and no DCS.

Energetic and physical limitations on the breaching performance of large whales.

The considerable power needed for large whales to leap out of the water may represent the single most expensive burst maneuver found in nature. However, the mechanics and energetic costs associated with the breaching behaviors of large whales remain poorly understood. In this study we deployed whale-borne tags to measure the kinematics of breaching to test the hypothesis that these spectacular aerial displays are metabolically expensive.

Chronic dietary exposure to polystyrene microplastics in maturing Japanese medaka (Oryzias latipes).

Fish studies report consumption of microplastics (MPs) in the field, and concern exists over associated risks. However, laboratory studies with adult fish are scarce. In this study, outbred and see-through Japanese medaka (Oryzias latipes) were fed diets amended with 500, 1000, or 2000 μg/g 10 μm fluorescent spherical polystyrene microplastics (MPs) for 10 weeks during their maturation from juveniles to spawning adults.