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Tag: Marine Science

  • Reviving Underwater Forest Inspires Global Marine Restoration

    Reviving Underwater Forest Inspires Global Marine Restoration

    Newswise — Human actions have caused significant harm to ecosystems and biodiversity worldwide, but there is a glimmer of hope for the future through ecosystem restoration. Researchers investigating the rejuvenation of underwater seaweed forests, crucial for nourishing and sheltering various species, have discovered that a decade of restoration endeavors has enabled a damaged forest to recover to a level of abundance and vitality similar to undisturbed forests.

    Dr. Emma Cebrian, the lead author of the study published in Frontiers in Marine Science and affiliated with the Centre d’Estudis Avançats de Blanes, emphasized the significance of macroalgal forests, which are present on more than a third of the world’s coastlines and serve as the foundation for entire ecosystems. The study focused on the restoration efforts carried out in the Bay of Maó, Menorca, in 2011, where a species of macroalgae was reintroduced to its former thriving habitat. The researchers observed that after a decade, the associated algal species returned to the area, accompanied by the reestablishment of ecosystem functions they provide.

    Under the sea

    In their study, Dr. Cebrian and her team employed a trait-based methodology to examine the functional restoration of seaweed forests. They aimed to establish a connection between the restoration efforts and the forest’s ability to function similarly to its pre-damaged state. Specifically, the researchers focused on Gongolaria barbata, a critical “canopy-forming” species that plays a crucial role in sustaining seaweed forests. By investigating five different locations of this species, the team aimed to gain insights into how the restoration of such key species can contribute to the revitalization of the entire ecosystem.

    Cristina Galobart, the study’s first author, who is also affiliated with the Centre d’Estudis Avançats de Blanes, highlighted the significance of canopy-forming macroalgae among all seaweeds. She likened their role to that of trees in a terrestrial forest, as they provide essential structure to the ecosystem. By altering factors such as light and water flow, these macroalgae have a profound influence on the local environment. This, in turn, leads to the creation of ecological niches that can be exploited by other species, allowing them to thrive and benefit from these modifications.

    In the assessment of restoration projects, particularly in marine ecosystems where such initiatives are less established, there is a tendency to focus on short timescales. However, projects involving slowly maturing species require longer durations for comprehensive evaluation. While we have gained understanding regarding the restoration of vegetation structure and species diversity, lingering questions remain regarding how an ecosystem regains its functional capabilities over time.

    In order to assess the functioning of the ecosystem, it is crucial to examine quantifiable traits in the target species that reflect the overall health of the ecosystem. The research team opted to investigate a comprehensive set of 14 traits, including characteristics such as specimen size and the growth rate of species with longer lifespans or slower growth patterns. The presence of species that require more time to mature or grow larger can serve as an indicator of a healthier ecosystem, as it suggests that the environment is better equipped to support their needs.

    The research team examined several distinct locations to gather data for their study. These included an actively restored locality, where restoration activities had been taking place for a decade, a nearby locality where the restored macroalgae had expanded beyond the initial restoration area, a neighboring locality that had not undergone restoration, and two reference localities that had remained undisturbed. Samples were collected from each location for further identification and analysis. Subsequently, the samples were dried and weighed to quantify the abundance of each species present.

    Growing strong

    The team’s findings revealed that the restored locality exhibited a greater diversity of species compared to the untouched locality and the area where restoration efforts had spread beyond the initial boundaries. Interestingly, the restored locality showcased a similar species composition to the reference samples, indicating a successful restoration outcome. Furthermore, the restored locality exhibited a higher level of functional richness compared to one of the reference forests, even though it did not consist of the exact species that the scientists had initially anticipated.

    The study highlighted that restored ecosystems may comprise different species compared to their original counterparts while still fulfilling similar ecological niches and supporting local biodiversity. The restored locality displayed enhanced structural complexity and encompassed species with longer lifespans, indicating a crucial sign of long-term recovery. This aspect is significant as it increases the potential for the seaweed forest to provide shelter and support to other organisms. Moreover, the increased diversity in the restored locality holds promising implications for the future. A more diverse seaweed forest has the potential to better respond to environmental challenges, ensuring its resilience and sustainability.

    “We demonstrated that a single restoration action, plus the removal of the cause of degradation, can lead to the recovery of not only a single species but also the associated ecosystem functions,” said Cebrian. “Adding information from other restoration initiatives will help to completely understand how functionality is recovered in different habitats, species, or environmental conditions.”

     

    Frontiers

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  • Most effective ways of foraging can attract predators, scientists find

    Most effective ways of foraging can attract predators, scientists find

    BYLINE: Laura Thomas

    Newswise — Animals using the most of efficient methods of searching for resources may well pay with their lives, scientists at the University of Bristol have discovered.

    The findings, published today in Behavioral Ecology, reveal why animals may not always use a searching strategy that maximises results.

    How animals move through their habitat, particularly in search for food, is a major question in biology, and has application in how animals will respond to environmental change.

    Numerous studies have demonstrated that a special kind of movement, known as Lévy motion, increases the ability to find resources because it includes long-distance moves between areas being searched, as well as periods of concentrated searching in one area. It has also been shown that a range of animals use this kind of movement.

    This study is the first to demonstrate a potential cost of Lévy motion in an experiment, showing prey using Lévy motion are targeted twice as often as prey using Brownian motion – the movement observed in molecules in a gas, and thus a baseline expectation.

    Professor Christos Ioannou from Bristol’s School of Biological Sciences explained: “We show that this is because the predators prefer to target prey that are moving with straighter paths of motion, possibly because this makes the future position of the prey more predictable.”

    Professor Ioannou and his team used a virtual prey approach. They developed a computer simulation of the prey which are identical in size, colour, speed etc but differ in how they turn.

    The video was then played to stickleback fish in a tank by projecting the video onto a translucent screen. This allowed the fish to see the prey, and for researchers to capture and record their choices.

    “By using an experimental design that presents virtual prey on a screen to real predators, we can control everything about the prey and isolate the variable we’re interested in – here, movement – while also using real animals,” continued Professor Ioannou.

    This study demonstrates that prey animals might not always use a searching strategy that maximises finding a resource because there might be costs that were, previous to the study, unknown. This might explain why some studies have found animals use different kinds of searches other than Lévy motion.

    He added: “Our study shows, for the first time, that animals using a common and very effective way of searching for resources may actually pay a cost of being more susceptible to predators.

    “Going forward, we want to look at whether the prey of sticklebacks show Levy or Brownian motion.

    “More broadly, our study predicts that prey animals should be less likely to demonstrate Lévy motion than apex predators.”

     

    Paper:

    ‘Virtual prey with Lévy motion are preferentially attacked by predatory fish’ by Christos Ioannou et al in Behavioral Ecology.

    University of Bristol

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  • “Golden” Fossils Show Exceptional Preservation Origins

    “Golden” Fossils Show Exceptional Preservation Origins

    Newswise — All that glitters is not gold, or even fool’s gold in the case of fossils.

    A recent study by scientists at The University of Texas at Austin and collaborators found that many of the fossils from Germany’s Posidonia shale do not get their gleam from pyrite, commonly known as fool’s gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed.

    The discovery is important for understanding how the fossils — which are among the world’s best-preserved specimens of sea life from the Early Jurassic — came to form in the first place, and the role that oxygen in the environment had in their formation.

    “When you go to the quarries, golden ammonites peek out from black shale slabs,” said study co-author Rowan Martindale, an associate professor at the UT Jackson School of Geosciences. “But surprisingly, we struggled to find pyrite in the fossils. Even the fossils that looked golden, are preserved as phosphate minerals with yellow calcite. This dramatically changes our view of this famous fossil deposit.”

    The research was published in Earth Science Reviews. Drew Muscente, a former assistant professor at Cornell College and former Jackson School postdoctoral researcher, led the study.

    The fossils of the Posidonia Shale date back to 183 million years ago, and include rare soft-bodied specimens such as ichthyosaur embryos, squids with ink-sacs, and lobsters. To learn more about the fossilization conditions that led to such exquisite preservation, the researchers put dozens of samples under scanning electron microscopes to study their chemical composition.

    “I couldn’t wait to get them in my microscope and help tell their preservational story,” said co-author Jim Schiffbauer, an associate professor at the University of Missouri Department of Geological Sciences, who handled some of the larger samples.

    The researchers found that in every instance, the fossils were primarily made up of phosphate minerals even though the surrounding black shale rock was dotted with microscopic clusters of pyrite crystals, called framboids.

    “I spent days looking for the framboids on the fossil,” said co-author Sinjini Sinha, a doctoral student at the Jackson School. “For some of the specimens, I counted 800 framboids on the matrix while there was maybe three or four on the fossils.”

    The fact that pyrite and phosphate are found in different places on the specimens is important because it reveals key details about the fossilization environment. Pyrite forms in anoxic (without oxygen) environments, but phosphate minerals need oxygen. The research suggests that although an anoxic seafloor sets the stage for fossilization — keeping decay and predators at bay — it took a pulse of oxygen to drive the chemical reactions needed for fossilization.

    These findings complement earlier research carried out by the team on the geochemical conditions of sites known for their caches of exceptionally preserved fossils, called konservat-lagerstätten. However, the results of these studies contradict long-standing theories about the conditions needed for exceptional fossil preservation in the Posidonia.

    “It’s been thought for a long time that the anoxia causes the exceptional preservation, but it doesn’t directly help,” said Sinha. “It helps with making the environment conducive to faster fossilization, which leads to the preservation, but it’s oxygenation that’s enhancing preservation.”

    It turns out, the oxygenation — and the phosphate and accompanying minerals — also enhanced the fossil’s shine.

    The research was funded by Cornell College and the National Science Foundation. The Posidonia fossil specimens used in this study are now part of the collections at the Jackson School’s Non-Vertebrate Paleontology Laboratory.

    University of Texas at Austin (UT Austin)

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  • Fish Growth Unaffected by Spawning

    Fish Growth Unaffected by Spawning

    Newswise — Contrary to what is stated in biology textbooks, the growth of fish doesn’t slow down when and because they start spawning. In fact, their growth accelerates after they reproduce, according to a new article published in Science. 

     “Fish don’t have to choose between growth or reproduction because, in the real world, they don’t occur simultaneously but rather sequentially,” says University of British Columbia (UBC) fisheries researcher Dr. Daniel Pauly, co-author of the Science technical comment with Dr. Rainer Froese, senior scientist at Germany’s Geomar Helmholtz Centre for Ocean Research.

    “Fish use only 10% to 20% of their energy for each of these two activities, the rest being mainly devoted to other activities, such as darting about when predators approach,” adds Dr. Pauly, who leads the Sea Around Us research initiative at UBC. “This means that reducing the movement rate, given the same food and oxygen consumption, can easily produce the savings required for growth or reproduction. This is the reason, incidentally, why fish farmers raise fish which have been selected to be calmer than their wild congeners.”

    The comment is a response to a previous study which erroneously claims growth ceases when fish reproduce because they dedicate all of their energy to such activity.

    Based on a growth equation widely used in fisheries science, the authors of the initial paper claimed that the growth of the Atlantic horse mackerel from the North Sea stock slows down with the onset of reproduction. Yet, they did not report on the size at which this fish actually matures and spawn.

    Dr. Pauly and Dr. Froese revisited the study and included maturation and spawning trends. Their work demonstrated that the very evidence advanced to support the traditional, textbook claim shows the contrary: horse mackerel actually grow faster after spawning for the first time.

    “This case is not unique,” Dr. Pauly says. “If we ran the numbers using the growth parameters and size at first maturity available for hundreds of fish in FishBase, the online encyclopedia of fish, we would get the same s results.”

    According to the comment, there’s a lack of support for the notion that reproduction impacts growth, even in mammals. “Pets that are neutered or spayed exhibit the same growth trajectories as their parents,” says Dr. Froese. “Also, the dominant males in harem-building species, such as sea lions, don’t cease growing and they become bigger than bachelors, even though they are dedicating a lot of their resources to reproduction.”

    In fish, the oxygen needed for growth is supplied by gills surfaces through which water must flow – a bit like the wind through blinds. Gill surface area grows in two dimensions, that is, in length and width, but they cannot keep up with fish’s bodies, which grow in three dimensions, length, width and depth. Thus, as fish get bigger, they have less gill surface area and their gills provide less oxygen per unit volume or weight.

    “There is a point when the growth of individual fish leads to a decline in its relative gill surface area, which generates a critical level of oxygen supply. This ‘tells’ the fish that it has reached a stage in which it should mature and spawn,” says Dr. Pauly. “When a fish spawns, it loses gonadal tissue that previously had to be supplied with oxygen and thus its relative gill area increases, which facilitates renewed growth until the next spawning season.”

    University of British Columbia

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  • Robot fish makes splash with motion breakthrough

    Robot fish makes splash with motion breakthrough

    Newswise — A coil-powered robot fish designed by scientists at the University of Bristol could make underwater exploration more accessible.

    The robot fish was fitted with a twisted and coiled polymer (TCP) to drive it forward, a light-weight low cost device that relies on temperature change to generate movement, which also limits its speed.

    A TCP works by contracting like muscles when heated, converting the energy into mechanical motion. The TCP used in this work is warmed by Joule heating – the pass of current through an electrical conductor produces thermal energy and heats up the conductor. By minimising the distance between the TCP on one side of the robot fish and the spring on the other, this activates the fin at the rear, enabling the robot fish to reach new speeds. The undulating flapping of its rear fin was measured at a frequency of 2Hz, two waves per second. The frequency of the electric current is the same as the frequency of tail flap.  

    The findings, published at the 6th IEEE-RAS International Conference on Soft Robotics (RoboSoft 2023), provide a new route to raising the actuation – the action of causing a machine or device to operate – frequency of TCPs through thermomechanical design and shows the possibility of using TCPs at high frequency in aqueous environments.

    Lead author Tsam Lung You from Bristol’s Department of Engineering Mathematics said: “Twisted and coiled polymer (TCP) actuator is a promising novel actuator, exhibiting attractive properties of light weight, low-cost high energy density and simple fabrication process.

    “They can be made from very easily assessable materials such as a fishing line and they contract and provide linear actuation when heated up. However, because of the time needed for heat dissipation during the relaxation phase, this makes them slow.”

    By optimising the structural design of the TCP-spring antagonistic muscle pair and bringing their anchor points closer together, it allowed the posterior fin to swing at a larger angle for the same amount of TCP actuation.

    Although this requires greater force, TCP is a strong actuator with high work energy density, and is still able to drive the fin.

    Until now, TCPs have been mostly used for applications such as wearable devices and robotic hands. This work opens up more areas of application where TCP can be used, such as marine robots for underwater exploration and monitoring.

    Tsam Lung You added: “Our robotic fish swam at the fastest actuation frequency found in a real TCP application and also the highest locomotion speed of a TCP application so far.

    “This is really exciting as it opens up more opportunities of TCP application in different areas.”

    The team now plan to expand the scale and develop a knifefish-inspired TCP-driven ribbon fin robot that can swim agilely in water.

     

    Paper:

    ‘Robotic Fish driven by Twisted and Coiled Polymer Actuators at High Frequencies’ by Tsam Lung You et al at the 6th IEEE-RAS International Conference on Soft Robotics (RoboSoft 2023).

    University of Bristol

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  • Researchers Combat Lake Algae Blooms with Floating Filtration

    Researchers Combat Lake Algae Blooms with Floating Filtration

    Newswise — Climate change and human activity have been putting pressure on water bodies worldwide, and Canada’s vast network of lakes is no exception. Over the past decades, increasing nutrient levels have led to a process called eutrophication, in the shallow lakes dotting Quebec’s Laurentian region north of Montreal. These changes have led to a surge in algae blooms, rendering the lakes unusable and possibly disrupting the natural ecosystem.

    Restoring these lakes to a healthier condition is a complicated and expensive undertaking, but a new method being investigated by Concordia researchers in the Department of Building, Civil and Environmental Engineering may cut down on both costs and labour in an environmentally friendly way.

    Writing in the journal Water, the researchers describe a system of floating geotextile filters that efficiently remove suspended solids, algae and the nutrients from a shallow lake.  While the project is still in development, the researchers say they believe it has the potential to scale up. This technology could then benefit the health of larger bodies of water such as ponds, rivers, coastal areas and bays.

    The study is led by PhD student Antônio Cavalcante Pereira and Professor Catherine Mulligan. Research associate Dileep Palakkeel Veetil and Sam Bhat of Titan Environmental Containment are also contributors.

    Non-chemical solutions

    Over the summer and early fall seasons of 2019 and 2020, the researchers placed six geotextile layers in a floating filtration unit at Lac Caron. Lac Caron is a shallow eutrophic lake with a maximum depth of 2.6 metres located in Ste-Anne-des-Lacs, about 75 kilometres north of Montreal. The lake has been under a recreational advisory since 2008 due to excessive algae growth.

    The Plexiglas filtration device was made to float by an inflatable rubber tube placed in the centre of an enclosed area. The area was cordoned off by using geotextile turbidity curtains. The specialized curtains hang down from the water surface to reach the lakebed, or near to it, to prevent suspended solid interactions with the rest of the lake.

    Water samples from the lake and the contained areas were collected every two to three days. The specimens were then analyzed for levels of turbidity, suspended solids (TSS), phosphorus, blue-green-algae-phycocyanin (BGA-PC), chlorophyll-a and more.

    The analysis results were encouraging.

    The analysis results were encouraging, according to average removal efficiencies in 2019 and 2020. The researchers compared the filtered lake water to the non-filtered lake water and found the following:

    • Turbidity reduced 53 per cent in 2019/17 per cent in 2020
    • TSS by from 22 per cent/36 per cent
    • Phosphorus by 49 per cent/18 per cent
    • BGA-PC by 57 per cent/34 per cent
    • Chlorophyll-a by 56 per cent/32 per cent.

    Pereira says the year-over-year differences are the result of heterogeneous water quality in lakes due to distinct climate and algae growth patterns. A large, visible algae bloom was visible in 2019, while 2020’s algae was more dispersed throughout the whole water body.

    “Expanding our system for large lake remediation is a long-term goal. But the novelty of this project is the that we just use the in-situ water filtration as a remediating method for eutrophic water bodies,” says Pereira. “We did not add any chemicals to the lake, but we still managed to get good results: algae suppression and turbidity decreases for an entire recreational season.”

    An evolving long-term project

    Mulligan adds that this paper is part of a series that is based on work that first began back in 2008. The project has gone through subsequent iterations over the years and in other lakes in the region.

    The shallow lakes studied in the past were often created by developers excavating existing lakes and incompletely cutting down trees. However, several recent factors are contributing to recurring excessive algae growth. These factors include the continual degradation of fragmentary tree stumps, along with possible nutrient release from runoff and the lack of natural hydrological patterns.

    “It can be a challenge because water quality changes from year to year,” says Mulligan. “When those eutrophic water bodies are subjected to warmer temperatures, they tend to be much more affected by excessive algal blooms.”

    This research was funded by NSERC, Concordia University and Titan Environmental Containment.

    Read the cited paper: “An In-Situ Geotextile Filtration Method for Suspended Solids Attenuation and Algae Suppression in a Canadian Eutrophic Lake”

    Concordia University

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  • Stripped to the bone

    Stripped to the bone

    Natural disasters can devastate a region, abruptly killing the species that form an ecosystem’s structure. But how this transpires can influence recovery. While fires scorch the landscape to the ground, a heatwave leaves an army of wooden staves in its wake. Storm surges and coral bleaching do something similar underwater.

    University of California, Santa Barbara

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  • Scientists discover hidden crab diversity among coral reefs

    Scientists discover hidden crab diversity among coral reefs

    BYLINE: Jerald Pinson

    Newswise — The Indo-West Pacific is the largest, most biodiverse marine ecosystem on Earth, and many of the species it supports have comparably wide ranges. Writing in “The Origin of Species,” Charles Darwin noted that “… many fish range from the Pacific into the Indian Ocean, and many shells are common to the eastern islands of the Pacific and the eastern shores of Africa, on almost exactly opposite meridians of latitude.”

    At first glance, the same pattern appears to be true for crabs. Chlorodielline crabs, common on coral reefs, look so similar that scientists have struggled to distinguish species in the group based solely on appearance. But a new study reveals a surprising exception to the rule of uniformity across the Indo-West Pacific. While chlorodielline crab species with non-overlapping ranges are often nearly identical, those that occupy the same region have a unique feature.

    “They all look the same, until you compare their gonopods, which are structurally complex and very species specific,” said lead author and former Florida Museum of Natural History postdoctoral researcher Robert Lasley.

    Gonopods are specialized appendages used for reproduction that have evolved multiple times in different arthropod groups, including crustaceans, moths and butterflies, and millipedes. They’re variously used for sperm transfer and clasping, and in crabs, they sometimes come equipped with elaborate frills that give them the appearance of a spatula with a mohawk.

    Lasley, who is currently the curator of Crustacea at the University of Guam’s Biorepository, wanted to see if there was any pattern to the seemingly endless, undirected variation in their gonopods. To do that, he needed a close look at species across the Indo-West Pacific and assiduously collected specimens for more than a decade. He participated in numerous marine field forays in the Red Sea, Singapore, Australia, and the Phoenix Islands, hovering inches above their reefscapes in search of crabs hiding among the coral bric-a-brac.

    Chlorodielline crabs are especially diverse in what’s known as the coral triangle, where open sea is punctuated by a vast archipelago that stretches from Indonesia to the Solomon Islands. The shallow waters around these islands support roughly 76% of the world’s coral species and more than a quarter of all coral reef fishes. Chlorodielline crabs, most of which grow no larger than a corn kernel, sit near the base of the food chain in these ecosystems.

    “They’re among the most abundant coral reef crustaceans, which makes them very important,” Lasley said. “They live in what are essentially apartment buildings made out of dead coral, and there are so many of them that any time you pick up a piece of reef rubble, they spill out.”

    Before Lasley could determine why they had such wildly different gonopods, he first had to figure out how chlorodielline species are related to each other, which he accomplished through an analysis of DNA extracted from museum specimens. The authors then added information regarding the range of each species and the shape of their gonopods.

    What they found led them to one of marine biology’s most perplexing mysteries. There are a few key ingredients natural selection needs to make new species, but two of the most crucial are genetic variation and isolation. On land, roaming animals become isolated all the time, but in marine environments, this step in the speciation process can be harder to achieve. Many marine invertebrates — including crabs — have a larval stage, in which individuals drift across the world’s oceans in the form of microscopic plankton. With their strong capacity for long-distance dispersal, how do they remain isolated long enough for evolution to generate diversity?

    Naturalists like Darwin saw the Indo West Pacific as one vast body of water, uninterrupted by geographic barriers, like ocean rifts or unproductive dead zones, that would otherwise act like a catalyst in the process of speciation.

    The results of this study suggest sheer distance and time can also act as barriers. Many chlorodielline crabs have ranges that extend across the entirety of the Indo-West Pacific. The genetic analysis revealed these cryptic species have slowly accumulated differences in their DNA over millions of years.

    But it wasn’t until close relatives were reunited after an extended separation that those genetic differences visibly manifested in a single, peculiar way. In almost every case, close relatives with overlapping ranges had uniquely shaped gonopods but otherwise looked exactly the same.

    “What we can say is these crabs start genetically diverging in different geographic areas, and then the divergence of gonopods is an important piece of the speciation process that happens at the tail end of things,” he said.

    Lasley isn’t sure why these gonopods only begin to change when two species are in close proximity, but he suspects it’s something inherent in the way these crabs reproduce, which he intends to test in future studies. For now, the results indicate that far more variation exists at the heart of Earth’s most species-rich marine ecosystem than previously suspected, and the engine driving its diversity has yet to be entirely discovered.

    Additional authors of the study include Nathaniel Evans of the University of the Ryukyus, Gustav Paulay and Francois Michonneau of the Florida Museum of Natural History, Amanda Windsor of the National Museum of Natural History, Irwansyah of Sylah Kuala University, and Peter Ng of the Lee Kong Chian Natural History Museum.

    Funding for the study was provided in part by the National Science Foundation (grants DEB 1856245 and GECCO 1457769), the Gordon and Betty Moore Foundation, the Alfred P. Sloan Foundation and the Japan Society for the Promotion of Science (P22078)

    University of Florida

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  • Noise harming ocean invertebrates and ecosystems

    Noise harming ocean invertebrates and ecosystems

    Newswise — Noise from human activities is harming ocean invertebrates and ecosystems, new research shows.

    Scientists reviewed hundreds of studies on the impact of noise on marine invertebrates (such as crabs, molluscs, squid, prawns and worms).

    They concluded that noise caused by humans is harming invertebrates in numerous ways, from cellular level to entire ecosystems.

    The international team, including Universitat Politècnica de Catalunya – BarcelonaTech (UPC) and the University of Exeter, call for urgent research to investigate and mitigate these impacts.

    “Many people are surprised to discover that invertebrates can even perceive sounds, but in fact sound is fundamental to their survival,” said first author Dr Marta Solé, from UPC.

    “Light doesn’t travel very well in water but sound does, and invertebrates use sound in a variety of ways.

    “Human activities – especially shipping – are changing the ocean soundscape rapidly, and our study brings together the latest evidence on the impacts of this.”

    The study highlights the multiple impacts of anthropogenic (human) noise on invertebrates:

    • It can delay hatching and egg development in crustaceans, and significantly increase abnormalities and death rates among larvae of crustaceans, bivalves (eg mussels and oysters) and gastropods (eg snails).
    • Low-frequency sounds can cause injuries and even death. For example, research has shown that sound from underwater explosions can kill blue crabs. After an increase of cephalopods (eg squid and octopus) washing up on beaches in Spain, research showed that noise had damaged their statocysts (hearing organs that help them navigate).
    • Impacts on behaviour include many species displaying a “startle” reaction in response to loud sounds. Long-term exposure to noise also affects behaviour. For example, ship sounds limit the ability of shore crabs to change colour to camouflage themselves
    • Physiological changes have also been discovered. For example, Mediterranean common cuttlefish showed changes in the protein content due sound exposure – with some of the affected proteins related to stress. In another study, permanent high-level exposure to sound caused a significant reduction in growth rate and reproduction, an increase in aggressiveness and mortality rate, and a reduction in feed intake of shrimp.
    • By changing the behaviour and health of predators and prey in complex food webs, noise can affect entire ecosystems – and the researchers say more research is needed to investigate this.

    Recent studies have revealed that a wide range of invertebrates are sensitive to sounds, especially via sensory organs whose original function is to allow maintaining equilibrium in the water column and sensing gravity.

    Invertebrates can detect underwater sound through three types of sensory systems: “superficial” receptors on their body surface, internal “statocyst” receptors (equivalent of ears), and flexible “chordotonal” appendages that sense vibrations.

    They can also produce sounds – ranging from the “cough” of scallops to the creaks made by lobsters, crayfish, shrimps and crabs, possibly to ward off predators.

    “Our study underlines that these animals exist in a rich underwater soundscape,” said Dr Sophie Nedelec, from the University of Exeter.

    “We urgently need to know more about the impacts of noise pollution on these animals and ecosystems.

    “Considering that noise can affect invertebrates from cellular to ecosystems level, we need to bring together interdisciplinary expertise to embrace a holistic vision of the problem.

    “Given the many pressures being caused by humans – including from climate change and fisheries – we must do everything we can to limit underwater noise.”

    Ships and boats are the main sources of marine noise, but a wide range of other activities including drilling, dredging and sonar also cause noise.

    Seabed mining in international waters could be permitted for this first time later this year, and a recent study by Exeter researchers raised concerns about the noise impacts on wildlife.

    The paper, published in the journal Frontiers in Marine Science, is entitled: “Marine invertebrates and noise.”

    University of Exeter

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  • 19th Century ‘dinner plate’ still useful in ocean science

    19th Century ‘dinner plate’ still useful in ocean science

    Newswise — A simple 19th Century tool is still useful to ocean scientists in the age of satellites, new research shows.

    A Secchi disk –  historically called a “dinner plate” by sailors – is used in the open ocean to measure concentrations of microscopic algae called phytoplankton.

    It works by lowering the white disk into the water and recording the depth at which it disappears.

    In the new study, a research team including the University of Exeter, Plymouth Marine Laboratory, Vrije Universiteit (Netherlands) and the Italian Institute of Marine Sciences (ISMAR) compared the performance of Secchi disks with satellites and high-performance chromatography.

    Secchi disks performed almost as well as modern methods at monitoring phytoplankton abundance – meaning Secchi measurements going back more than a century can help scientists understand long-term changes in the ocean.

    “Phytoplankton produce half the world’s oxygen and form the base of ocean food webs, so monitoring them helps us track everything from climate change to the health of ecosystems,” said Dr Bob Brewin, from the Centre for Geography and Environmental Science on Exeter’s Penryn Campus in Cornwall.

    “New technology undoubtedly gives us new opportunities, but our study shows Secchi disks do a good job of estimating chlorophyll (a way of measuring phytoplankton abundance) – which means we should be able to integrate data from the past with modern measurements.

    “This gives us a priceless source of long-term data on how our oceans are changing.”

    Secchi disks are still used all around the world to monitor ocean biomass and water quality, and co-author Dr Jaime Pitarch, from ISMAR, said the findings support their continued use.

    “It’s a simple, cheap tool, but our research shows it’s also remarkably effective,” he said.

    In fact, researchers including Dr Brewin at Exeter, are working on a project that will use 3D-printed Secchi disks to monitor water quality in lakes in India and Africa, and coastal regions of the US.

    Prior to the 1850s, mariners used a variety of objects (in the same way as Secchi disks) to help with navigation, including cloths, pans and plates.

    It was the Vatican astronomer Angelo Secchi, invited by the Papal Navy Commander Alessandro Cialdi to join a scientific cruise to study the murkiness of the sea in 1865, who standardised the method.

    The measurements in the new study were collected on Atlantic Meridional Transect cruises, and Dr Brewin’s work is funded by a UKRI Future Leader Fellowship.

    The paper, published in the journal Frontiers in Marine Science, is entitled: “Evaluating historic and modern optical techniques for monitoring phytoplankton biomass in the Atlantic Ocean.”

    University of Exeter

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  • Unique hybrid reefs deployed off Miami Beach

    Unique hybrid reefs deployed off Miami Beach

    BYLINE: Robert C. Jones Jr. and Janette Neuwahl Tannen

    Newswise — The first piece of a series of concrete structures was lowered into the water off the coast of Miami Beach on Wednesday morning, a massive crane on the deck of a floating barge hoisting the unit into the air and sinking it to the seabed. 

    During the next six hours, crewmembers aboard the barge would repeat that process until the structures, some stacked on top of each other, were settled on the seafloor, 14 feet below the surface. 

    To casual observers onshore, the daylong operation might have seemed routine. But this maritime activity was hardly run-of-the-mill. 

    In a project that could pave the way for greater efforts to protect coastlines from sea level rise and storm surge and serve as an innovative base structure to develop thriving coral reefs, a team of researchers and scientists from the University of Miami sunk 27 interlocking concrete structures that will form two hybrid reef units 1,000 feet offshore of North Beach Oceanside Park, at the northern edge of Miami Beach. 

    The units are the centerpiece of a project called Engineering Coastal Resilience Through Hybrid Reef Restoration, or ECoREEF, which combines cement- and nature-based strategies to foster coastal resilience. Supported by the University’s Laboratory for Integrative Knowledge (U-LINK) and the City of Miami Beach, the project was developed at a time when coral reefs are struggling to survive. A recent study indicates that half of the world’s living coral reefs have died since the 1950s. Meanwhile, other research has shown that healthy and complex coral reefs are able to buffer up to 97 percent of the energy from waves and can also reduce flooding frequency.

    “Coral reefs are disappearing at alarming rates throughout the world as a result of disease and warming oceans, so our reefs have lost a lot of the structure they need to reduce wave energy,” said ECoREEF lead investigator, Diego Lirman, an associate professor of marine biology and ecology at the University’s Rosenstiel School of Marine, Atmospheric, and Earth Science. “By placing these [hybrid] reefs near the shoreline and planting stress-tolerant corals on them, we hope to recover some of the lost services provided by healthy reefs, such as coastal protection, and to build a habitat for organisms like fish and lobsters.” 

    One of the hollow structures submerged this week was shaped like a trapezoid, with rocks on its outer surface to mimic the texture of coral reefs and to attract marine life. The other unit is a series of hexagons, the iconic honeycomb-like shape that is being incorporated into more and more projects, including the powerful Webb Telescope. Perforated to allow seawater to flow through them, the hollow, hexagonal SEAHIVE structures—tubes that look like honeycomb and each weighing 2,500 pounds—are stacked in a pyramid-like shape and attached to a few solid concrete SEAHIVEs to enhance the stability of the structure. 

    To build the hybrid structures, researchers also used an eco-friendly concrete mixture, with composite reinforcements instead of steel, both for durability and to attract marine life. 

    Haus and Rhode-Barbarigos peer through a six-foot-tall perforated SEAHIVE unit, which they designed with other faculty members, on the barge that lowered dozens of the units into the ocean.

    “Designing structures to dissipate wave energy while providing a hospitable environment for corals has been a challenge,” said Landolf Rhode-Barbarigos, an assistant professor in the College of Engineering, and one of the project’s lead investigators. “There are no design guidelines for nature, but hopefully this can be translated into something bigger and provide novel solutions for coastal protection.” 

    It was Rhode-Barbarigos, along with Lirman, marine biologist Andrew Baker, ocean scientist Brian Haus, sustainable architect Sonia Chao, and communications expert Jyotika Ramaprasad, who joined forces in 2018 to address challenges of coastal resilience. They hope the ECoREEF project will lead to a better understanding of the types of structures that can help protect South Florida’s vulnerable coastline from erosion and storm surge. 

    “We want to see how these two different alternatives for a hybrid, engineered structure and a natural reef compare,” Haus said. “This is a research installation, so we’ll be examining it in a variety of ways.” 

    Corals grown at the Rosenstiel School’s three nurseries will eventually be attached to the hybrid reefs, allowing them to thrive and replace some of the area’s many coral reefs lost to disease and bleaching that is the result of warming ocean temperatures. 

    “We are hoping that we can get baby corals to attach and get a community that looks similar to a natural reef developing on these structures over time,” Lirman said.  

    But for now, the reefs must get acclimated to their new underwater environment. 

    Divers and drones will help monitor the structures; and soon, researchers will install current meters and wave sensors from the U.S. Geological Survey to measure wave energy and flow on the surface of the reefs, according to Brian Haus, professor and chair of ocean sciences at the Rosenstiel School. 

    After two previous attempts to deploy the structures were called off because of inclement weather, ideal conditions—calm waters and little to no wind—made it possible for crews to sink the structures. 

    Onboard the barge which carried the hybrid reefs—after a tugboat had brought them more than 100-nautical-miles from Fort Pierce to Miami Beach—Haus and Rhode-Barbarigos helped orchestrate the deployment, directing the crane that lowered the structures into the water and making sure the reefs were positioned and stacked correctly on the seabed. A diver who patrolled the seafloor ensured the structures aligned properly.

    “We got our hands a little bit dirty today, but it was worth it,” said Haus, who oversees the Rosenstiel School’s 75-foot-long, 38,000-gallon Alfred C. Glassell, Jr. SUSTAIN Laboratory wind-wave tank, which researchers used to test small-scale versions of the hybrid reefs.  

    Should a tropical cyclone threaten or even strike South Florida this coming hurricane season, the hybrid reefs could get their first big test, which is why the team went through a meticulous permitting process, Rhode-Barbarigos said.

    A grant from U-LINK helped jump-start the project, and the group soon partnered with the City of Miami Beach. The U-LINK initiative was founded in 2018 to offer interdisciplinary faculty teams seed funding to devise novel solutions to pressing societal issues. Since then, 40 other teams have been formed, and many of them have garnered additional external funding. Last summer, Baker, Lirman, Rhode-Barbarigos and Haus, among others, received a massive grant from the Defense Advanced Research Projects Agency (DARPA), a division of the U.S. Department of Defense, to scale up their designs and help protect military and civilian infrastructure along the coast. 

    “This EcoReefs project will give us a test bed for this technology, before we do a deployment of a much larger structure for the DARPA grant elsewhere in Florida,” Lirman pointed out.   

    While the U-LINK project was evolving, Rhode-Barbarigos was also working with Haus and College of Engineering faculty members Antonio Nanni, Esber Andiroglu, and Prannoy Suraneni to develop the SEAHIVE structure through grants from the National Comparative Highway Research Program and the Florida Department of Transportation. Initially created as an alternative to traditional seawalls because of their ability to mitigate wave energy, the honeycomb-shaped SEAHIVE units are also set to be tested at two other South Florida locations. 

    Miami Beach officials are eager to see how both hybrid reefs perform in the waters off North Beach Oceanside Park. 

    “The launch of this experimental [hybrid] reef marks a pivotal moment in our efforts to protect Miami Beach from coastal erosion and restore our coral ecosystem,” said Ricky Arriola, a Miami Beach commissioner. “Not only will this innovative solution help safeguard our shores, but it will also drive ecotourism and further establish Miami Beach as a leader in sustainable coastal management.” 

    Amy Knowles, the city’s chief resilience officer, agreed. “We can’t wait to see how this hybrid reef grows,” she said. “Coral reefs are an important part of marine life, and our coastal resilience to storm surge and sea level rise for Miami Beach and our broader region.” 

    For the faculty members who worked on the project since its inception four years ago, this deployment marked an achievement.

    “It’s been a long adventure, so we’re understandably excited,” Rhode-Barbarigos said. “It’s a milestone moment because we’ll be able to learn from these units both from an engineering and ecological perspective. What we accomplished today is the end of one phase, but the beginning of another.”

    University of Miami

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  • Toothed whales catch food in the deep using vocal fry

    Toothed whales catch food in the deep using vocal fry

    Newswise — Dolphins and other toothed whales are large brained top predators that captivate our imagination; they are extremely social, they cooperate, and can hunt prey down to 2 km deep in complete darkness with echolocation.

    All these remarkable behaviors are mediated using sound that travels far and fast in murky and dark waters. However, it has remained a mystery how these amazing animals make their rich vocal repertoires in the deep.

    Now a new study in the prestigious journal Science reports that toothed whales evolved an air-driven nasal sound source that operates at different vocal registers like the human voice.

    The study was led by Professor Coen Elemans, voice scientist at the Department of Biology, University of Southern Denmark and Professor Peter Madsen, whale biologist at the Department of Biology, Aarhus University in Denmark.  

    The study shows that toothed whales, like humans, have at least three voice registers; the vocal fry register (also known as creaky voice, which produces the lowest tones), the chest register (which is our normal speaking voice) and the falsetto register (which produces even higher frequencies).

    “Vocal fry is a normal voice register that is often used in American English. Kim Kardashian, Kate Perry and Scarlet Johannsen are well-known people using this register”, Professor Elemans says.

    According to the new research, toothed whales use this vocal fry register to produce their echolocation calls to catch prey.

    “During vocal fry, the vocal folds are only open for a very short time, and therefore it takes very little breathing air to use this register”, Elemans adds.

    “And this air-economy makes it especially ideal for echolocation”, says Professor Madsen, adding:

    “During deep dives, all air is compressed to a tiny fraction of the volume on the surface”.

    Toothed whales dive as deep as 2.000 meters and catch more fish than the human fishing industry. When they hunt in the deep and murky waters, they produce short, powerful, ultrasonic echolocation clicks at rates up to 700 per second to locate, track and catch prey.

    “Thus vocal fry allows whales access to the richest food niches on earth; the deep ocean”, says Madsen.

    “While vocal fry may be controversial in humans and may be perceived as everything from annoying to authoritative, it doubtlessly made toothed whales an evolutionary success story”, Elemans adds.

    It was previously thought that toothed whales make sounds with their larynx just as other mammals, but 40 years ago it became clear that this is not the case; they somehow use their nose to produce sound. In the new study, the Danish research team has uncovered, what exactly goes on using high-speed video through endoscopes:

    The toothed whales have evolved an air-driven sound production system in their nose, that functions physically analogous to laryngeal and syringeal sound production in mammals and birds – but its location is far from the same.

    “Evolution has moved it from the trachea into the nose, which allowed much higher driving pressures – up to 5 times what a trumpet player can generate – without damaging lung tissues”, says Madsen.

    “This high driving pressure allows toothed whales to make the loudest sounds of any animal on the planet,” Elemans adds.

    At depths over 100m, whale lungs collapse to avoid compression sickness and are thus no good for air supply, and the remaining air is found in the nasal passages of the skull. This provides a small, but sufficient airspace to produce echolocating sound at astonishing depths of 2000 meters.

    When echolocating, toothed whales pressurize air in their bony nose and lets it pass structures called phonic lips that vibrate just as human vocal folds. Their acceleration produces sound waves that travel through the skull to the front of the head.

    In addition to echolocation, toothed whales make a huge array of sounds for their complex social communication.

    “Some species, like killer and pilot whales, make very complex calls that are learned and passed on culturally like human dialects”, says Madsen.

    In their study the researcher show that these sounds are made by the phonic lips vibrating in the chest and falsetto registers. They filmed the phonic lips using several different approaches, using both trained dolphins and animals in the wild that were moving freely with a small tag that recorded their sounds. The in vivo recordings were done at Dolfinarium Harderwijk in Holland.

    “It took us close to 10 years to develop new techniques, gather and analyze all our data”, says Elemans.

    University of Southern Denmark

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  • Blue whale foraging and reproduction are related to environmental conditions, study shows

    Blue whale foraging and reproduction are related to environmental conditions, study shows

    Newswise — NEWPORT, Ore. – A new study of New Zealand blue whales’ vocalizations indicates the whales are present year-round in the South Taranaki Bight and their behavior is influenced by environmental conditions in the region.

    The findings are a significant advancement in researchers’ understanding of the habitat use and behavior of this population of blue whales, which Oregon State University researchers first identified as genetically distinct from other blue whale populations less than a decade ago.  

    “We went from not knowing 10 years ago whether this was a distinct population to now understanding these whales’ ecology and their response to changing environmental conditions,” said the study’s lead author, Dawn Barlow, a postdoctoral scholar in OSU’s Marine Mammal Institute. “These findings can inform conservation management of this blue whale population and their habitat.”

    The patterns and intensity of the whales’ calls and songs over two years showed strong seasonality in their foraging and breeding behavior, and the vocalizations changed based on environmental conditions such as a documented marine heatwave, Barlow said.

    “During the marine heatwave, feeding-related calls were reduced, reflecting poor foraging conditions during that period,” Barlow said. “But we also saw changes in vocalizations in the next breeding period, an indication that they put less effort into reproduction following a period of poor feeding conditions.”

    The study was just published in the journal Ecology and Evolution. Barlow conducted the research as a doctoral student in the Geospatial Ecology of Marine Megafauna Laboratory at Hatfield Marine Science Center in Newport, led by associate professor Leigh Torres, a co-author of the new paper.

    Blue whales are the largest of all whales and are found in all oceans except the Arctic. Their populations were depleted due to commercial whaling in the early 1900s, and today they are listed as endangered under the International Union for Conservation of Nature’s Red List of Threatened Species.

    The New Zealand whales’ habitat overlaps with a wide range of commercial activities, including oil and gas exploration and extraction, vessel traffic, fisheries, wind energy development and possible seabed mining.

    Torres first hypothesized in 2013 that the South Taranaki Bight, between New Zealand’s North and South Islands, was an undocumented blue whale feeding ground. Following comprehensive data collection efforts, and using multiple lines of evidence, Torres, Barlow and colleagues were able to document in 2018 that the population in this region was genetically distinct from other blue whale populations.

    Previous research was primarily based on observations researchers made during visits to the region in the summer months. But the researchers wanted to know more about the whales’ behavior during other parts of the year. They placed five hydrophones – a type of underwater microphone – that recorded continuously between January 2016 and February 2018, with only brief gaps to retrieve data every six months.

    “Unlike many other baleen whales, this population stays in this region year-round,” Barlow said. “That means we can monitor what they are doing from one location. Listening is an effective way to do that.”

    The hydrophone recordings showed that the whales’ “D” calls were strongly correlated with oceanographic conditions related to upwelling in the spring and summer. Upwelling is a process where deeper, cooler water is pushed toward the surface; the nutrient-rich water supports aggregations of krill that the blue whales feed on. The whales’ D calls were more intense during periods of strong upwelling.

    The recordings also showed that the whales’ song vocalizations, which are produced by males and associated with breeding behavior, followed a highly seasonal pattern, with peak intensity in the fall. That timing aligns with past whaling records’ estimates of conception, Barlow said.

    The hydrophone evidence of the breeding behavior and the whales’ presence in the region year-round can influence the animals’ national threat classification status, which impacts management practices, the researchers said.

    Blue whales in New Zealand had been classified as migrant, but as a result of the research by Torres, Barlow and colleagues, the classification of has changed from migrant to data deficient. If the whales are reclassified as a resident population, that could impact management practices, but evidence of breeding in New Zealand is needed for that change to occur, the researchers said.

    “Although no one has actually documented blue whales mating – it is hard to observe that directly – the increase in song during the expected time of mating is a strong indication of breeding in New Zealand waters,” Torres said. “Our study adds more evidence that these are resident New Zealand blue whales.”

    Once the researchers were able to make the link between the whales’ behavior and their calls, they could then look at the calls and behavior relative to environmental patterns. Specifically, they noted how the whales’ foraging and breeding behavior changed during and after a 2016 marine heatwave.

    During the marine heatwave, there were fewer aggregations of krill for the whales to feed on, which the researchers documented in a previous study. The reduction in foraging behavior correlated to less intense D calls during that period, and in the next breeding season, the breeding songs were also less intense.

    The findings raise additional questions about how changing ocean conditions and human activity in the region are impacting the New Zealand blue whale population and reinforce the need for continued monitoring, the researchers said.

    “We have come so far in 10 years in our knowledge of these blue whales – from not knowing this population existed to now understanding their year-round use of this region for feeding, mating and nursing,” Torres said. “New Zealanders should be excited and proud that their country is home to its own unique population of blue whales. We hope our work helps Kiwis manage and protect these whales.”

    Additional coauthors are Holger Klinck, director of the Cornell University K. Lisa Yang Center for Conservation Bioacoustics, who also is affiliated with OSU’s Marine Mammal Institute; Dimitri Ponirakis of Cornell; and Trevor Branch of the University of Washington. The Marine Mammal Institute is part of Oregon State’s College of Agricultural Sciences.

    Oregon State University

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  • Shrinking age distribution of spawning salmon raises climate resilience concerns

    Shrinking age distribution of spawning salmon raises climate resilience concerns

    Newswise — By returning to spawn in the Sacramento River at different ages, Chinook salmon lessen the potential impact of a bad year and increase the stability of their population in the face of climate variability, according to a new study by scientists at UC Santa Cruz and NOAA Fisheries.

    Unfortunately, spawning Chinook salmon are increasingly younger and concentrated within fewer age groups, with the oldest age classes of spawners rarely seen in recent years. The new study, published February 27 in the Canadian Journal of Fisheries and Aquatic Sciences, suggests changes in hatchery practices and fishery management could help restore the age structure of the salmon population and make it more resilient to climate change.

    The researchers focused on Sacramento River fall-run Chinook salmon, which contribute heavily to the salmon fisheries of California and southern Oregon. This population is particularly susceptible to the effects of increasingly severe drought conditions driven by climate change.

    “As we get more variable climate conditions, with greater extremes of rainfall and drought, we are going to see more ‘boom-and-bust’ population dynamics unless we start to restore the age structure of the population, which can spread out the effects of good and bad years across time,” said senior author Eric Palkovacs, professor of ecology and evolutionary biology and director of the Fisheries Collaborative Program at UC Santa Cruz.

    If most of the salmon return to spawn at the same age, one bad year could be devastating for the overall population. Spreading the risk over multiple years is an example of what ecologists call the “portfolio effect,” like a financial portfolio that spreads risk over multiple investments.

    First author Paul Carvalho, a postdoctoral fellow with the Fisheries Collaborative Program, explained that juvenile salmon are especially vulnerable to the effects of drought as they migrate to the ocean from freshwater rivers and streams.

    “We focused on the impacts of drought on the survival of juvenile salmon, but drought conditions can also increase mortality of returning adult salmon as they migrate upstream to spawn,” he said.

    Carvalho developed a life cycle model of the Sacramento River fall-run Chinook salmon population to simulate the effects of different drought scenarios and other variables on the population. The model was grounded in data from field studies, such as research by NOAA Fisheries scientists that quantified the relationship between river flows and survival rates of juvenile salmon.

    The model allowed the researchers to assess the effects of different mechanisms that can affect the age structure of the population. A century ago, most of the spawning salmon returning to the Sacramento River watershed were four years old, and some were as old as six years. Today, however, six-year-old fish are rarely observed and most of the spawners are three years old.

    “Historically, you would have seen huge salmon coming back at older ages, but over the past century they’ve gotten smaller and younger,” Palkovacs said. “The dominant age class is now 3 years, and there are very few even at age 5, so there’s been a big shift in the age structure.”

    Decreased size and age at maturity is a classic pattern of fisheries-induced evolution. A high mortality rate for older fish selects for fish that mature at earlier ages, because a fish that dies before it can spawn doesn’t pass on its genes. But fishing pressure is not the only factor driving changes in the age structure of the salmon population. Hatchery practices can also inadvertently select for earlier maturation.

    “It’s pretty clear that current hatchery practices are resulting in very homogeneous populations returning at age three,” Palkovacs said. “Rather than producing a uniform product, it would be better to increase the diversity of the age structure by selecting older, larger fish and making sure you get as many of them into the spawning population as possible.”

    Carvalho noted that improving the age structure of the population by selecting for fish that spend more years at sea (delayed maturation) would be most effective in combination with reduced harvest rates.

    “Because the fish remain in the ocean longer, they are exposed to the fishery and other causes of mortality for a longer period, so that reduces the number returning to spawn if you don’t reduce fishing pressure on those older age classes,” he said.

    Overall, the results show that maintaining or increasing the age structure through reduced mortality and delayed maturation improves the stability of the salmon population, buffering against the adverse effects of drought and making the population more resilient in an increasingly variable climate.

    “Regardless of the mechanism, whether it’s reduced mortality or delayed maturation that’s driving it, increasing the diversity of the age structure will increase the stability of the population,” Carvalho said.

    In addition to Carvalho and Palkovacs, the coauthors of the paper include William Satterthwaite, Michael O’Farrell, and Cameron Speir at the NOAA Southwest Fisheries Science Center. This work was supported by the Cooperative Institute for Marine, Earth, and Atmospheric Systems (CIMEAS) and the NOAA Quantitative Ecology and Socioeconomics Training (QUEST) Program.

    University of California, Santa Cruz

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  • Researchers find several oceanic bottom circulation collapses in the past 4.7 million years

    Researchers find several oceanic bottom circulation collapses in the past 4.7 million years

    Newswise — Antarctic bottom water (AABW) covers more than two-thirds of the global ocean bottom, and its formation has recently decreased. However, its long-term variability has not been well understood.

    Researchers led by Prof. DENG Chenglong from the Institute of Geology and Geophysics (IGG) of the Chinese Academy of Sciences (CAS) and their collaborators have reconstructed AABW history back to approximately 4.7 million years ago (mya). They found that AABW has collapsed several times and such collapses might have induced moisture transport to fuel the Northern Hemisphere glaciation (NHG).

    This work was published in Science Advances on Feb. 24.

    The study was based on a 36-mm-diameter Fe-Mn nodule from the Eastern Pacific, located 5,050 m below sea level. The nodule was collected by Guangzhou Marine Geological Survey, China Geological Survey.

    Magnetic scanning was an important factor in providing precise dating results. “This is a key, though the final dating was obtained by an integration with 10Be/9Be, flux of metal Co, and astronomical tuning,” said Dr. YI Liang from Tongji University, first author of the study and a postdoc at IGG/CAS.

    “Since AABW is the main provider of oxygen in the ocean bottom region, we used various scientific methods to identify the relation between metal accumulation in the Fe-Mn nodule and oceanic redox conditions,” said Prof. DENG. “Ni, Mn, and Cu contents are used to indicate AABW changes.”

    These results show that seawater oxygen has experienced a linear increase in the Eastern Pacific since around 3.4 mya. This trend agrees with the observation of the Antarctic Ice Sheet (AIS), suggesting a covariation between them.

    Comparing the AABW record with other geological records from the past million years, the researchers found a glacial enhancement of oceanic bottom circulation. This observation implies that atmospheric CO2 may have been regularly stored in the deep ocean when Earth’s climate was cold, e.g., during past glacial periods.

    The comparisons clearly highlighted seven intervals of poor seawater oxygen, suggesting AABW influence was reduced to a much lower level. These periods are known as AABW collapse and accompanied an enhancement of North Atlantic Deepwater (NADW) as well as key stages of NHG history, such as when NHG became intensified or amplified.

    Although we don’t know what will happen in response to ongoing AIS melting and AABW slowing, AABW collapse might have pulled the Earth into a harsher glacial climate several times in the past.

    Chinese Academy of Sciences

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  • Record low sea ice cover in the Antarctic

    Record low sea ice cover in the Antarctic

    Newswise — There is currently less sea ice in the Antarctic than at any time in the forty years since the beginning of satellite observation: in early February 2023, only 2.20 million square kilometres of the Southern Ocean were covered with sea ice. Researchers from the Alfred Wegener Institute and the University of Bremen analyse the situation for the Sea Ice Portal. January 2023 had already set a new record for its monthly mean extent (3.22 million square kilometres), even though the melting phase in the Southern Hemisphere continues until the end of February. The current expedition team on board RV Polarstern has just reported virtually ice-free conditions in its current research area, the Bellingshausen Sea.

    “On 8 February 2023, at 2.20 million square kilometres, the Antarctic sea ice extent had already dropped below the previous record minimum from 2022 (2.27 million square kilometres on 24 February 2022). Since the sea ice melting in the Antarctic will most likely continue in the second half of the month, we can’t say yet when the record low will be reached or how much more sea ice will melt between now and then,” says Prof Christian Haas, Head of the Sea Ice Physics Section at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), with regard to the current developments in the Antarctic. “The rapid decline in sea ice over the past six years is quite remarkable, since the ice cover hardly changed at all in the thirty-five years before. It is still unclear whether what we are seeing is the beginning of a rapid end to summer sea ice in the Antarctic, or if it is merely the beginning of a new phase characterised by low but still stable sea ice cover in the summer.”

    The melting has progressed since December 2022, especially in the Bellingshausen and Amundsen Seas in the West Antarctic; the former is virtually ice-free. That is also where the research vessel Polarstern currently is, exploring the evidence left behind of past glacials and interglacials. According to expedition leader and AWI geophysicist Prof Karsten Gohl, who is now in the region for the seventh time, having first come in 1994: “I have never seen such an extreme, ice-free situation here before. The continental shelf, an area the size of Germany, is now completely ice-free. Though these conditions are advantageous for our vessel-based fieldwork, it is still troubling to consider how quickly this change has taken place.”

    In the course of the year, the Antarctic sea ice generally reaches its maximum extent in September or October and its minimum extent in February. In some regions, the sea ice melts completely in summer. In winter, the cold climate throughout the Antarctic promotes the rapid formation of new sea ice. At its maximum, the sea ice cover in the Antarctic is generally between 18 and 20 million square kilometres. In summer, it dwindles to roughly 3 million square kilometres, displaying far more natural annual variability than ice in the Arctic.

    Further, Antarctic sea ice is much thinner than its Arctic counterpart and appears only seasonally – which explains why, for a very long time, its development was considered impossible to predict beyond a matter of days. In recent years, however, science has uncovered several mechanisms for predicting the development of sea ice on seasonal time scales. Knowing the sea ice presence weeks to months in advance is of great interest to Antarctic shipping.

    Analyses of the current sea ice extent, conducted by the Sea Ice Portal team, show that, for the entire month of January 2023, the ice was at its lowest-ever extent recorded for the time of year since the beginning of record-keeping in 1979. The monthly mean value was 3.22 million square kilometres, ca. 478,000 square kilometres (an area roughly the size of Sweden) below the previous minimum from 2017. With regard to its long-term development, the Antarctic sea ice shows a declining trend of 2.6 percent per decade. This is the eighth consecutive year in which the mean sea-ice extent in January has been below the long-term trend.

    This intense melting could be due to unusually high air temperatures to the west and east of the Antarctic Peninsula, which were ca. 1.5 °C above the long-term average. In addition, the Southern Annular Mode (SAM) is in a strongly positive phase, which influences the prevailing wind circulation in the Antarctic. In a positive SAM phase (like today), a low-pressure anomaly forms over the Antarctic, while a high-pressure anomaly develops over the middle latitudes. This intensifies the westerly winds and causes them to contract toward the Antarctic. As a result, upwelling of circumpolar deep water on the continental shelf intensifies in the Antarctic, promoting sea-ice retreat. More importantly, it also intensifies the melting of ice shelves, an essential aspect for future global sea-level rise.

    Unravelling the geological evolution of the West Antarctic Ice Sheet, i.e., the massive glaciers that cover the Antarctic continent and fuel the ice shelves, is the proclaimed goal of the current Polarstern expedition. Doing so, it is hoped, will allow us to make more accurate statements on the ice sheet’s future development, and therefore on sea-level rise in the face of constant climate change. For example, the last interglacial, 120,000 years ago, and a prolonged warm period in the Pliocene roughly 3.5 million years ago, are considered analogous to today. In both past periods, the warming was exclusively due to gradual changes in Earth’s orbit – today, these are supplemented by carbon dioxide emissions, which are produced by the use of fossil fuels and accumulate in the atmosphere. The insights gleaned from the ice sheets’ history are intended to help estimate how rapidly and extensively they will melt when certain tipping points of today’s rapid anthropogenic climate change are exceeded. In this regard, researchers use geophysical and geological methods to investigate marine sediments at the sea floor, which, as archives of past ice-sheet movements, hold valuable information.

    Historical records also reflect the tremendous changes. For example, in the Antarctic summer 125 years ago, the Belgian research vessel Belgica was trapped in the massive pack ice for more than a year – in exactly the same region where the Polarstern can now operate in completely ice-free waters. The photographs and diaries of the Belgica’s crew offer a unique chronicle of the ice conditions in the Bellingshausen Sea at the dawn of the industrial age, which climate researchers often use as a benchmark for comparison with today’s climate change.

    You can find more detailed analyses at the Sea Ice Portal: https://www.meereisportal.de/.

    For the latest news from the Polarstern expedition, check out the Polarstern app https://follow-polarstern.awi.de/ or the Polarstern blog https://blogs.helmholtz.de/polarstern/en/ , not to mention the blog on the 125th anniversary of the Belgica expedition (English only): https://125yearsbelgica.com/

    Alfred Wegener Institute for Polar and Marine Research

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  • “It’s me!” fish recognizes itself in photographs

    “It’s me!” fish recognizes itself in photographs

    Newswise — A research team led by Specially Appointed Professor Masanori Kohda from the Graduate School of Science at the Osaka Metropolitan University has demonstrated that fish think “it’s me” when they see themselves in a picture, for the first time in animals. The researchers found that the determining factor was not seeing their own body but seeing their face. These findings have been published in the Proceedings of the National Academy of Sciences.

    In this study, relevant experiments were conducted with Labroides dimidiatus, commonly known as a cleaner fish, which are known to be able to recognize themselves in mirrors and regularly attack other unfamiliar cleaner fish who intrude on their territory. Each cleaner fish was presented with four photographs: a photo of themselves; a photo of an unfamiliar cleaner; a photo of their own face on an unfamiliar cleaner’s body; and a photo of unfamiliar cleaner’s face on their own body. Interestingly, the cleaner fish did not attack photos with their own faces but did attack those with the faces of unfamiliar cleaner fish. Together these results indicate that the cleaner fish determined who was in the photograph based on the face in the photo but not the body in the similar way humans do.

    To negate the possibility that the fish considered photographs of themselves as very close companions, a photograph mark-test was conducted. Fish were presented with a photograph where a parasite-like mark was placed on their throat. Six of the eight individuals that saw the photograph of themselves with a parasite mark were observed to rub their throats to clean it off. While showing those same fish pictures of themselves without parasite marks or of a familiar cleaner fish with parasite marks did not cause them to rub their throats.

    “This study is the first to demonstrate that fish have an internal sense of self. Since the target animal is a fish, this finding suggests that nearly all social vertebrates also have this higher sense of self,” stated Professor Kohda.

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    About OMU

    Osaka Metropolitan University is a new public university established by a merger between Osaka City University and Osaka Prefecture University in April 2022. For more science news, see https://www.omu.ac.jp/en/, and follow @OsakaMetUniv_en and #OMUScience.

    Osaka Metropolitan University

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  • Study reveals salps play outsize role in damping global warming

    Study reveals salps play outsize role in damping global warming

    Newswise — Humans continue to amplify global warming by emitting billions of tons of carbon dioxide into the atmosphere each year. A new study reveals that a distant human relative plays an outsize role in damping the impacts of this greenhouse gas by pumping large amounts of carbon from the ocean surface to the deep sea, where it contributes nothing to current warming.

    The study, led by Dr. Deborah Steinberg of William & Mary’s Virginia Institute of Marine Science, appeared in the latest issue of Global Biogeochemical Cycles. It reports on research conducted as part of EXPORTS, a 4-year, multi-institutional field program funded by NASA. Co-authors hail from marine institutes in Maine, Bermuda, California, Newfoundland, British Columbia, and Alaska.

    The goal of EXPORTS, for EXport Processes in the Ocean from RemoTe Sensing, is to combine shipboard and satellite observations to more accurately quantify the global impact of the “biological pump.” This is a suite of biological processes that transport carbon and other organic matter from sunlit surface waters to the deep sea, effectively removing carbon dioxide from the surface ocean and atmosphere. Tiny drifting animals called zooplankton play a key role in the pump by eating phytoplankton, which incorporate carbon from carbon dioxide into their tissues during photosynthesis, then exporting that carbon to depth.

    During a month-long EXPORTS expedition to the northeast Pacific Ocean in 2018, Steinberg and colleagues chanced upon a large bloom of a poorly studied player in the biological pump: a species of gelatinous zooplankton named Salpa aspera. Like other salps, these “jelly barrels” begin life with a notochord—the structure that develops into the spinal cord in humans and other vertebrates—and as adults drift through the world’s oceans like tiny transparent whales, filtering microscopic plants afloat in the water. 

    Three features keyed the team’s interest in salps, and S. aspera in particular. One is that these organisms can reproduce asexually, rapidly cloning into immense blooms under the right conditions. Second is that S. aspera is bigger and filters more water than most other zooplankton, thus producing larger, heavier fecal pellets. Third is that it migrates up and down through the water each day, rising to feed on phytoplankton during the cover of night and jetting to the perpetual darkness of the deep sea during sunlit hours to avoid its own predators, which include sea turtles, marine birds, and fishes.

    Together, these features had led researchers to suspect that salps might play an important role in the biological pump, as large blooms of these relatively bulky zooplankton could effectively transport carbon to depth through their heavy, fast-sinking fecal pellets; vertical migrations that give those pellets a head start on their journey to depth; and the sinking of countless salp carcasses during a bloom (individual salps live only a few weeks).

    But the proof is in the pudding, and the ephemeral life cycle and uneven distribution of salps has long challenged efforts to study their role in carbon export and deep-sea food webs. “Salps follow a ‘bloom or bust’ life cycle,” says Steinberg, “with populations that are inherently patchy in space and time. That makes it hard to observe or model their contribution to the export of carbon to the deep sea.”

    During the 2018 EXPORTS expedition to the Pacific, Steinberg and colleagues were able to overcome these challenges by deploying a wide range of ocean-observation tools, from traditional plankton nets and sediment traps to underwater video recorders and sonar-based computer models. Moreover, by using two research vessels—the 277-ft Roger Revelleand the 238-ft Sally Ride—the scientists were able to observe conditions not only inside the salp bloom but in surrounding waters, providing a broader geographic context for their study.

    The results of the team’s unprecedented field campaign were clear. “High salp abundances, combined with unique features of their ecology and physiology, lead to an outsized role in the biological pump,” says Steinberg. 

    To put things in perspective, the observed salp bloom covered more than 4,000 square miles (~11,000 km2), about the size of Connecticut. With onboard experiments showing salps capable of exporting a daily average of 9 milligrams of carbon through each square meter at 100 meters below the bloom, the amount of carbon exported to the deep sea was about 100 metric tons per day. For comparison, a typical passenger car emits 4.6 metric tons per year. Comparing these values shows the carbon removed from the climate system each day of the bloom is equal to taking 7,500 cars off the road. Adjusting these values using the team’s highest measured rate of salp-mediated export (34 mg of C per day) increases the carbon offset to more than 28,000 vehicles.

    Moving forward, the team calls for increased recognition of the key role that salps play in global carbon export. “Blooms like the one we observed often go undetected,” says Steinberg, “and their contributions to the biological pump are rarely quantified, even in some of the best-studied regions of the world’s oceans.” Incorporation of salp dynamics into a recent carbon-cycle model illustrates the potential of salp-mediated export. In this global model, salps and other tunicates exported 700 million metric tons of carbon to the deep sea each year, equal to emissions from more than 150 million cars. 

    “Greater use of new technologies, such as adding video imaging systems to autonomous floats, would help detect these salp blooms,” says Steinberg. “Our study serves as a ‘call to arms’ to better detect and quantify these processes, using technology and sampling schemes that enable their inclusion in measurements and models of the biological carbon pump.”

    Virginia Institute of Marine Science

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  • Decades-old crustaceans coaxed from lake mud give up genetic secrets revealing evolution in action

    Decades-old crustaceans coaxed from lake mud give up genetic secrets revealing evolution in action

    Newswise — Human actions are changing the environment at an unprecedented rate. Plant and animal populations must try to keep up with these human-accelerated changes, often by trying to rapidly evolve tolerance to changing conditions.

    University of Oklahoma researchers Lawrence Weider, professor of biology, and Matthew Wersebe, a biology doctoral candidate, demonstrated rapid evolution in action by sequencing the genomes of a population of Daphnia pulicaria, an aquatic crustacean, from a polluted lake.  

    The research, which was conducted as part of Wersebe’s doctoral dissertation, was recently published in the Proceedings of the National Academy of Sciences.  Wersebe and Weider revived decades-old Daphnia resting eggs from lake sediments, a method known as resurrection ecology, which has been refined in Weider’s lab over the past several decades. They then sequenced the entire genomes of 54 different Daphnia individuals from different points-in-time, allowing them to study the genetics and evolution of the population.

    The Daphnia were collected from Tanners Lake, located in Oakdale, Minnesota. Tanners Lake has suffered significant salt pollution, stemming from the widespread use of road deicing salts in its watershed.  

    Daphnia, also known as water fleas, play critical roles in environmental monitoring. For example, they have served as important test organisms in laboratories around the world for over a century because of their sensitivity to many environmental stressors such as chemicals. In nature, Daphnia act as a keystone species in freshwater food webs globally, where they feed on algae to help keep lake and reservoir water clean and serve as a food item for recreational and commercially important fish species.

    Wersebe’s and Weider’s results indicate that rapid adaptation to salt pollution may allow lake Daphnia to persist in the face of anthropogenic salinization, maintaining the food webs and ecosystem services that Daphnia support. However, the ability of these populations to adapt will depend on the speed at which these changes are occurring and the underlying genetic makeup of the impacted populations. 

    Over the past several years, many researchers have published results defining the scope and scale of lake salinization and recent research has highlighted the ecological impacts. However, to date, the evolutionary implications are not well known. Through their study, Wersebe and Weider reported signatures of natural selection throughout the genome near genes related to osmoregulation and ion regulation, key processes for dealing with high salt. Characterizing clones for salinity tolerance revealed evidence that genetic changes may underlie rapid evolution.  

    “Work like this is the first step in designing future studies incorporating recent technological advances, such as CRISPR gene editing, allowing the creation of comprehensive genotype-to-phenotype maps and predicting the role that genetic variation plays in creating diverse forms and functions,” Wersebe said. “In fact, we found a promising gene that appears not to work properly in the older Daphnia, but a functional copy of the gene is increasing in frequency – true evolution in action.”

    Future research using these advanced technologies for cutting and pasting the non-functional gene into Daphnia would be one way to better probe the effects that mutations have on complex phenotypic traits like salinity tolerance.  

    The work was funded by the OU Department of Biology Adams Summer Scholarship, Robberson OU Graduate College Grant, Hill Fund for Research in Biology, OU Graduate Student Senate Research Grant, American Museum of Natural History Theodore Roosevelt Grant and the National Science Foundation Biogeography of Behavior student seed grant awarded to Wersebe in support of graduate research. The study was facilitated by material and technical assistance from the University of Oklahoma Biological Station in Kingston, Oklahoma, and the St. Croix Watershed Research Station in Marine-on-St. Croix, Minnesota.  

    University of Oklahoma

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  • Penguins, Robots, The Ocean and more

    Penguins, Robots, The Ocean and more

    Newswise — Fieldwork in Antarctica is tricky, just ask University of Delaware scientist Matthew Breece. There is the 10-day trek to get there from Delaware, which includes a sometimes stomach-revolting four-day sail through Drake Passage, heavy research equipment to manage, limits on what you can pack. The temperatures are cool, averaging just above freezing at around 36 degrees Fahrenheit in the austral summer from October to February. Weather can change rapidly, too, relegating researchers indoors when conditions are poor and making for very long days in the field when conditions are pristine.

    But if you ask a scientist…or student…if the effort is worth it, the answer is a resounding YES!

    Marine biology students at Caesar Rodney High School in Camden, Delaware, got a firsthand look at what it’s like to conduct field research on penguins in Antarctica on Tuesday, Jan. 24, during a live video call with Matthew Breece, a research scientist in marine science and policy at the University of Delaware.

    “It’s fun, but also a lot of hard work,” said Breece, who guided the nearly 50 students through a virtual tour of Palmer Station, a United States research station situated on Anvers Island, Antarctica.

    Breece showed the students glaciers, laboratory experiments, research equipment and common areas, like the library, and shared stories and answered questions about living among wildlife including penguins, whales and seals. 

    “Wildlife have the right of way here,” said Breece, explaining how researchers were scrambling over rocks to get to their research vessels earlier in the week, while a crab-eater seal sunned itself on the boat dock. Gentoo penguins can swim 22 miles per hour, which is faster than the research boats can go, while Adélie penguins can only swim 10-12 mph.

    Breece and his colleagues are examining the feeding habits and predator-prey interactions of Adélie and Gentoo penguins in the region using an autonomous underwater vehicle (AUV). The AUV, called a REMUS, is equipped with a high-resolution echosounder that uses sonar to collect data about food resources that are available to marine animals in Palmer Deep Canyon on the West Antarctic Peninsula.

    Besides hearing from Breece, students also saw dramatic photographs from Antarctica and scientific charts used in the research.

    The new echosounder gives researchers a birds-eye view of what’s for lunch in the water. It was developed by Mark Moline, Maxwell P. and Mildred H. Harrington Professor of Marine Studies at UD and principal investigator on the project, and project co-PIs Kelly Benoit-Bird, senior scientist at Monterey Bay Aquarium Research Institute and Megan Cimino, assistant researcher at the Institute of Marine Sciences and assistant adjunct professor of ocean sciences at the University of California, Santa Cruz.

    “We switched to shorter wavelength frequencies to look at smaller things,” said Moline. “So, not only looking at the oceanography, but also the high-resolution food distribution of krill, copepods, fish and the species that eat them, like penguins.”

    The UD work complements the National Science Foundation’s ongoing Palmer Station Long-Term Ecological Research (LTER) study related to penguin population sizes and foraging ranges. The seabird component of the Palmer LTER research is led by Cimino, a UD alumna.

    Cimino has a second project with Carlos Moffat, a UD coastal physical oceanographer who also is in Antarctica serving as chief scientist of the Palmer LTER program, which has been collecting long-term ecological data for over 30 years. Collaborating institutions on the broader Palmer LTER study, led by Rutgers University and the Virginia Institute of Marine Science (VIMS), include researchers from UD, University of Virginia, Woods Hole Oceanographic Institution, University of Colorado, and University of California, Santa Cruz.

    Moffat also is conducting physical oceanography work as part of his NSF CAREER award to understand the dynamics of melting glaciers and how that impacts the ocean circulation and properties, such as salinity and temperature of the coastal ocean.

    “As the atmosphere is warming in this region of Antarctica, sea ice is decreasing and more glaciers are melting from the coast, physically changing the environment marine organisms are living in,” said Moffat. “One big question is what this means long term for marine organisms that live in these places, such as penguins, whales, seals and other wildlife. I see my contribution as trying to help them understand how the physical environment impacts the entire ecosystem.”

    From Antarctica to Delaware

    Lessons learned in Antarctica can help shed light on uncertainties about how sea level rise will evolve in other parts of the world, too. For instance, Delaware is a low-lying state with no area of the state more than eight miles from tidal waters. It is considered a big hotspot of sea level rise along the U.S. East Coast. And while sea levels are increasing on average around the world, due to ocean warming and melting ice from the continents, the distribution of sea level is very uneven. 

    “To understand what is going to happen in the future, we need to understand why sea levels are increasing and how it’s going to change over time,” said Moffat. “Antarctica is a good place to study this because change is happening very rapidly.”

    For most of the 20th century, the Palmer Station region was considered the fastest changing region in the southern hemisphere, while the Weddell Sea, which is located just around the corner of the Antarctic peninsula, had not changed as much. Over the last few years, researchers have begun to wonder whether the Weddell Sea has any influence on the West Antarctic Peninsula region or whether the regions are changing independently.

    To better understand these processes, Moffat’s team deployed two AUVs called gliders to sample the circulation close to the coast along the Antarctic peninsula, which is heavily influenced by the melting of glaciers. He and his students recovered oceanographic moorings that have been capturing data, such as water circulation currents, temperature and salinity, since early 2022. This is part of the West Antarctic Peninsula that has never been sampled before, so the team is eager to analyze the data.

    “I am particularly excited about the glider measurements, which I plan to add to my dissertation,” said Frederike (Rikki) Benz, a doctoral student in the Moffat lab. “It is especially interesting to be involved in the whole process from preparing, shipping and deploying to publishing.”

    Classrooms beyond campus

    For students, field research offers the opportunity for hands-on experience with sophisticated research instruments, data collection and analysis, troubleshooting and networking with researchers from other institutions. Sometimes those activities occur in remote regions of the world — like Antarctica.

    “The rarity of this experience comes with a sense of humility and responsibility to not take any moment for granted, a responsibility to ensure more opportunities are available for future students and scientists,” said Evan Quinter, who is pursuing a master’s degree in physical ocean science and engineering in the Moffat Lab.

    At Caesar Rodney High School, marine biology teachers Cristine Taylor and Sandra Ramsdell have just begun covering marine animals with their students. It is a fitting coincidence that made the live call with UD researchers both timely and meaningful.

    “Spending a day in class speaking with researchers was an awesome experience for our students,” said Taylor. “We are trying to encourage them to look at everything that goes into marine careers. Not every person is a marine biologist, there are computer scientists and engineers, ship captains and crew, and so many more people who can work in marine research.”

    University of Delaware

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