Constantine Alexander's blog

Our Sea, Our Life!

I am always star struck when I look at nature. Perhaps this is because we are all made from stardust forged in the heart of a star and infused with a whisper of celestial wisdom.

Like so many others, I have come to realize that our lives are completely dependent on nature that provides us with clean water, fruits, vegetables, grains, fuel, fresh air, seasonal climates, coastal protection, recreation and scenic landscapes around the world that will take your breath away. It is no wonder then that nature has been immortalized for centuries by poets, musicians, artists and explorers who have appreciated that which has too often been overlooked by others.

In spite of the extent to which we have unwittingly disturbed so many terrestrial and marine ecosystems in our quest for what is often termed as progress, nature in its infinite wisdom has so far been resilient against our unnatural and often toxic incursions, adaptable, forgiving and regenerative except in some localized areas which are experiencing an unnatural species extinction rate. This degradation signals to us that nature’s strength alone cannot endure the unnatural incursions that are increasingly reaching areas of the world previously thought to be impenetrable by man such as 1,500 meter depths at which fishermen can now trawl for orange roughy and areas beneath the blue-white Antarctic ice from which tons of krill on which whales feed are now being harvested for sport fishing bait, aquarium feeds and aquaculture.

After hearing from people all over the world who share a passion and concern for the preservation of life’s necessities as well as gifts from nature, this blog was launched to share with you international wildlife news, exciting environmental research activities, political action or inaction, and what each of us can do to ensure that the wisdom of nature endures for the benefit of us all as we are mere caretakers of nature for future generations of all species which have a right to thrive in and contribute to a healthy and beautiful world.

Constantine Alexander

EU Commissioner Potočnik: “EU Air Policy can go hand in hand with growth and jobs”

Ahead of the Green Week, taking place from 4 to 7 June, Commissioner for the Environment Janez Potočnik met leading environment journalist Sonja van Renssen to talk about EU air quality policy.

Topics discussed include:

• Air quality goals
• Revision of the Commission’s current air policy
• Air quality compliance
• Revision of the national emission ceilings Directive
• Methane and black carbon

 

New study shows predators affect the carbon cycle

Credit: Constantine Alexander

A new study shows that the predator-prey relationship can affect the flow of carbon through an ecosystem. This previously unmeasured influence on the environment may offer a new way of looking at biodiversity management and carbon storage for climate change.

The study, conducted by researchers at the Yale School of Forestry & Environmental Studies, comes out this week in the Proceedings of the National Academy of Sciences. It looks at the relationship between grasshoppers and spiders—herbivores and predators in the study's food chain—and how it affects the movement of carbon through a grassland ecosystem. Carbon, the basic building block of all organic tissue, moves through the food chain at varying speeds depending on whether it's being consumed or being stored in the bodies of plants. However, this pathway is seldom looked at in terms of specific animal responses like fear from predation.

"We're discovering that predators are having important effects on shaping the make-up of ecosystems," says Dr. Oswald Schmitz, professor of ecology and one of the co-authors of the study. "But we've not really spent a lot of time measuring how that translates into other functions like nutrient cycling and recycling."

The researchers manipulated the food chains of grassland ecosystem to see how the levels of carbon would change over time. Dr. Schmitz and his team created several controlled ecosystems: some that contained only native grasses and herbs, others that had plants and an herbivore grasshopper, and some others that had plants and herbivores along with a carnivore spider species—all three tiers of the food chain. In addition, a form of traceable carbon dioxide was injected into sample cages covered with Plexiglas, which allowed the team to track the carbon levels by periodically taking leaf, root, and dead animal samples.

The study found that the presence of spiders drove up the rate of carbon uptake by the plants by about 1.4 times more than when just grasshoppers were present and by 1.2 more times than when no animals were present. It was also revealed that the pattern of carbon storage in the plants changed when both herbivores and carnivores were present. The grasshoppers apparently were afraid of being eaten by the spiders and consumed less plant matter when the predators were around. The grasshoppers also shifted towards eating more herbs instead of grass under fearful scenarios.

At the same time, the grasses stored more carbon in their roots in a response to being disturbed at low levels when both herbivores and carnivores were present. In cases where only herbivores were present, the plants stored less carbon overall, likely due to the more intense eating habits of the herbivores that put pressure on plants to reduce their storage and breathe out carbon more. These stress impacts, then, caused both the plants and the herbivores to change their behaviors and change the composition of their local environment.

This has significance for biodiversity conservation and ecosystem management. Although the study was carried out on a small scale, it could inform practices done in much larger areas. Places such as the Alaskan wilderness, for example, are home to animals that have the same predator-and-prey dynamics that drive the carbon cycle, and so protecting lands and storing carbon could be linked at the same time. Appreciating the role of predators is also important currently, given that top predators are declining at rates faster than that of many other species in global trends of biodiversity loss.

"It's going to force some thinking about the vital roles of animals in regulating carbon," concludes Dr. Schmitz, pointing to the fact that the UN's body of scientific experts who study climate change don't consider these multiplier effects in their models. "People are arguing for a paradigm change."

Contact: Oswald Schmitz
203-432-5110
Yale School of Forestry & Environmental Studies

Pesticides significantly reduce biodiversity in aquatic environments

Current pesticide risk assessment falls short of protecting biodiversity

Common Bluetail (Ischnura senegalensis). Photo: André Künzelmann/UFZ (Place: Banaue/Phillippines)

The pesticides, many of which are currently used in Europe and Australia, are responsible for reducing the regional diversity of invertebrates in streams and rivers by up to 42 percent, researchers report in the Proceedings of the US Academy of Sciences (PNAS). Mikhail A. Beketov and Matthias Liess from the Helmholtz Centre for Environmental Research (UFZ) in Leipzig, together with Ben Kefford from the University of Technology, Sydney and Ralf B. Schäfer from the Institute for Environmental Sciences Landau, analysed the impact of pesticides, such as insecticides and fungicides, on the regional biodiversity of invertebrates in flowing waters using data from Germany, France and Victoria in Australia. The authors of the now-published study state that this is the first ever study which has investigated the effects of pesticides on regional biodiversity.

Pesticides, for example those used in agriculture, are among the most-investigated and regulated groups of pollutants. However, until now it was not known whether, or to which extent, and at what concentrations their use causes a reduction in biodiversity in aquatic environments. The researchers investigated these questions and compared the numbers of species in different regions: in the Hildesheimer Boerde near Braunschweig, in southern Victoria in Australia and in Brittany in France.

In both Europe and Australia, the researchers were able to demonstrate considerable losses in the regional biodiversity of aquatic insects and other freshwater invertebrates. A difference in biodiversity of 42 percent was found between non-contaminated and strongly-contaminated areas in Europe; in Australia, a decrease of 27 percent was demonstrated.

The researchers also discovered that the overall decrease in biodiversity is primarily due to the disappearance of several groups of species that are especially susceptible to pesticides. These mainly include representatives of the stoneflies, mayflies, caddisflies, and dragonflies and are important members of the food chain right up to fish and birds. Biological diversity in such aquatic environments can only be sustained by them because they ensure a regular exchange between surface and ground water, thus functioning as an indicator of water quality.

Protection concepts fall short of requirements

One worrying result from the study is that the impact of pesticides on these tiny creatures is already catastrophic at concentrations which are considered protective by current European regulation. The authors point out that the use of pesticides is an important driver for biodiversity loss and that legally-permitted maximum concentrations do not adequately protect the biodiversity of invertebrates in flowing waters. New concepts linking ecology with ecotoxicology are therefore urgently needed. "The current practice of risk assessment is like driving blind on the motorway", cautions the ecotoxicologist Matthias Liess. To date, the approval of pesticides has primarily been based on experimental work carried out in laboratories and artificial ecosystems. To be able to assess the ecological impact of such chemical substances properly, existing concepts need to be validated by investigations in real environments as soon as possible. "The latest results show that the aim of the UN Convention on Biological Diversity to slow down the decline in the number of species by 2020 is jeopardized. Pesticides will always have an impact on ecosystems, no matter how rigid protection concepts are, but realistic considerations regarding the level of protection required for the various ecosystems can only be made if validated assessment concepts are implemented." The threat to biodiversity from pesticides has obviously been underestimated in the past.

Citation: M.A. Beketov, B.J. Kefford, R.B. Schäfer, and M. Liess (2013): "Pesticides reduce regional biodiversity of stream invertebrates". PNAS, Early Edition. 17 June 2013, DOI: 10.1073/pnas.1305618110

Contact: Tilo Arnhold
49-341-235-1635
Helmholtz Association of German Research Centres

Submarine springs reveal how coral reefs respond to ocean acidification

Calcifying corals can grow under low pH conditions, although their carbonate skeletons are not dense and are more vulnerable to physical erosion. (Photo courtesy of A. Paytan)

Ocean acidification due to rising carbon dioxide levels will reduce the density of coral skeletons, making coral reefs more vulnerable to disruption and erosion, according to a new study of corals growing where submarine springs naturally lower the pH of seawater.

The study, led by researchers at the University of California, Santa Cruz, and published in the Proceedings of the National Academy of Sciences (PNAS), is the first to show that corals are not able to fully acclimate to low pH conditions in nature.

"People have seen similar effects in laboratory experiments," said coauthor Adina Paytan, a research scientist in the Institute of Marine Sciences at UC Santa Cruz. "We looked in places where the corals are exposed to low pH for their entire life span. The good news is that they don't just die. They are able to grow and calcify, but they are not producing robust structures."

With atmospheric carbon dioxide rising steadily, the oceans are absorbing more carbon dioxide, which lowers the pH of the surface waters. Ocean acidification refers to changes in seawater chemistry that move it closer to the acidic range of the pH scale, although seawater is not expected to become literally acidic. Paytan's team studied coral reefs along the Caribbean coastline of Mexico's Yucatan Peninsula where submarine springs lower the pH of the surrounding seawater in a localized, natural setting. The effect is similar to the widespread ocean acidification that is occurring as the oceans absorb increasing amounts of carbon dioxide from the atmosphere.

Led by first author Elizabeth Crook, a graduate student in Paytan's lab, the researchers deployed instruments to monitor seawater chemistry around the springs and removed skeletal cores from colonies of Porites astreoides, an important Caribbean reef-building coral. They performed CT scans of the core samples to measure their densities and determine annual calcification rates in the laboratory of coauthor Anne Cohen at Woods Hole Oceanographic Institution.

The results showed that coral calcification rates decrease significantly along a natural gradient in seawater pH. Ocean acidification lowers the concentration of carbonate ions in seawater, making it more difficult for corals to build their calcium carbonate skeletons.

"Carbonate ions are the building blocks they need to grow their skeletons. When the pH is lower the corals have to use more energy to accumulate these carbonate building blocks internally. As a result, the calcification rate is lower and they lay down less dense skeletons," Paytan said.

The reduced density of the coral skeletons makes them more vulnerable to mechanical erosion during storms, organisms that bore into corals, and parrotfish, which sometimes feed on corals. This could lead to a weakening of the reef framework and subsequent degradation of the complex coral reef ecosystem.

"There are likely to be major shifts in reef species and some loss of coral cover, but if ocean acidification is the only impact there won't be total destruction," Paytan said. "We need to protect corals from other stressors, such as pollution and overfishing. If we can control those, the impact of ocean acidification might not be as bad."

In addition to Crook, Cohen, and Paytan, the coauthors of the paper include Mario Rebolledo-Vieyra and Laura Hernandez of the Centro de Investigacion Cientifica de Yucatan. This research was funded by the National Science Foundation and UC-MEXUS.

Contact: Tim Stephens
831-459-2495
University of California - Santa Cruz

Study identifies travel choices for a smaller carbon footprint

Planes, trains, or automobiles: what's the most climate-friendly way to travel? A new study by researchers from IIASA and CICERO brings better estimates of how much personal travel impacts the climate.

The study, published in the journal Environmental Science and Technology by researchers at IIASA and Center for International Climate and Environmental Research (CICERO) calculates the climate impact for passenger trips of 500-1000 km—typical distances for business or holiday trips. It shows that while air travel continues to have the biggest climate impact per distance travelled, the choices that people make about how they drive or take public transport make a big difference in how much they contribute to climate change.

"Traveling alone in a large car can be as bad for the climate as flying, but driving with three in a small car could have an equally low impact as a train ride," says IIASA's Jens Borken-Kleefeld. A 1000 km trip alone in a big car could emit as much as 250 kg of carbon dioxide (CO2), the researchers calculate, while a train trip or carpooling in a small car could emit as little as 50 kg of CO2 for each traveler.

Air travel has by far the biggest impact on climate per distance traveled, because it can lead to contrails and formation of cirrus clouds that have a strong climate impact, as well as ozone. These mechanisms have a strong effect on the climate, but cause warming over much shorter periods of time than CO2.

The study focused on the short-lived greenhouse gases and aerosols emitted by both ground transportation and airplanes. In addition, the researchers accounted for vehicle occupancy and efficiency, based on real-world emissions data from cars, buses, trains, and airplanes in Europe.

"These components have not been regulated in the Kyoto Protocol," says Terje Berntsen, climate researcher at CICERO. "This means they risk being overlooked when comparing the climate impact from different travel choices."

Previous work and publicly available carbon footprint calculators estimate only averages for the whole transport system, at best. That means that they can miss big differences in climate impact that come from other pollutants, personal choices, and local mitigation measures.

Technologies to control air pollutant emissions from cars, buses, power plants, and trains effectively minimizes their climate impact, the study also shows—benefiting not just air quality but also climate change mitigation efforts. The researchers say that mitigation efforts should concentrate on improving fuel efficiency and developing low-carbon fuels.

While this is also important for aircraft, they say, more needs to be done to avoid the contrail and cirrus clouds. For people wanting to minimize their climate impact, Borken-Kleefeld says, "Try to avoid flying, driving alone, and driving big cars. Instead, when you can, choose the train, bus, or carpool with 2 to 3 people."

Citation: Borken-Kleefeld, Jens, Jan Fuglestvedt, and Terje Berntsen, 2013. Mode, load, and specific climate impact from passenger trips. Environmental Science and Technology. doi: 10.1021/es4003713

Contact: Katherine Leitzell
43-223-680-7316
International Institute for Applied Systems Analysis

IIASA is an international scientific institute that conducts research into the critical issues of global environmental, economic, technological, and social change that we face in the twenty-first century. Its findings provide valuable options to policy makers to shape the future of our changing world. IIASA is independent and funded by scientific institutions in Africa, the Americas, Asia, and Europe. 

 

EU LIFE+ project produces new river restoration guide

The LIFE+ Information and Communication project RESTORE has published a new guide to river restoration called Rivers by Design. The guide is aimed at planners, developers, architects and landscape architects and seeks to show them how to maximise the benefits of river restoration in development projects.

The guide explains the context and need for river restoration, illustrating how well-planned river restoration can increase ecological quality, reduce flood risk and create social and economic benefits. It explains to the target audience the crucial role they can play in delivering such projects to meet the needs of people and the environment.

The new publication provides guidance and step-by-step practical advice on planning river restoration projects to make sure sustainable development is achieved, maximising ecological, social and economic benefits. A large section of the guide presents examples of successful river restoration projects from Munich to Milton Keynes to inspire practitioners in their own planning.

RESTORE is a networking project to support river restoration practices across Europe.

A step-by-step guide for planners, developers, architects and landscape architects on how to maximise the benefits of river restoration in development projects.

Download Rivers by Design

UCLA climate study predicts dramatic loss in Southern California snowfall

By midcentury, snowfall on Los Angeles–area mountains will be 30 to 40 percent less than it was at the end of the 20th century, according to a UCLA study released today and led by UCLA climate expert Alex Hall.

The projected snow loss, a result of climate change, could get even worse by the end of the 21st century, depending on how the world reacts. Sustained action to reduce global greenhouse gas emissions could keep annual average snowfall levels steady after mid-century, but if emissions continue unabated, the study predicts that snowfall in Southern California mountains will be two-thirds less by the year 2100 than it was in the years leading up to 2000.

"Climate change has become inevitable, and we're going to lose a substantial amount of snow by midcentury," said Hall, a professor in UCLA's Department of Atmospheric and Oceanic Sciences and UCLA's Institute of the Environment and Sustainability. "But our choices matter. By the end of the century, there will be stark differences in how much snowfall remains, depending on whether we begin to mitigate greenhouse gas emissions."

"This science is clear and compelling: Los Angeles must begin today to prepare for climate change," said Los Angeles Mayor Antonio Villaraigosa. "We invested in this study and created the AdaptLA framework to craft innovative solutions and preserve our quality of life for the next generation of Angelenos."

Less snowfall in general and a complete loss of snow at some lower elevations doesn't just have implications for snow enthusiasts who enjoy skiing and sledding in the local mountains; it also could mean sizeable economic losses for snow-dependent businesses and communities. Less snow could also mean changes in the seasonal timing of local water resources, greater difficulty controlling floods, and damage to mountain and river ecosystems.

The impact to actual snow on the ground may be even greater because the researchers quantified snowfall but not snow melt, said Hall, whose previous research found the region will warm 4 to 5 degrees by midcentury. By then, researchers estimate, the snowpack could melt an average of 16 days sooner than it did in 2000. "We won't reach the 32-degree threshold for snow as often, so a greater percentage of precipitation will fall as rain instead of snow, particularly at lower elevations," Hall said. "Increased flooding is possible from the more frequent rains, and springtime runoff from melting snowpack will happen sooner."

"As a California resident, I spend my winters snowboarding in mountains throughout our amazing state," said Jeremy Jones, founder of Protect Our Winters, an environmental nonprofit composed of winter sports enthusiasts. "It breaks my heart to see America's great natural resources harmed by climate change. We must, immediately, begin to reduce greenhouse gas emissions. There is no choice."

The UCLA study, "Mid- and End-of-Century Snowfall in the Los Angeles Region," is the most detailed research yet examining how climate change will affect snowfall in the Southern California mountains. The report was produced by UCLA with funding from the city of Los Angeles, and in partnership with the Los Angeles Regional Collaborative for Climate Action and Sustainability at UCLA's Institute of the Environment and Sustainability. The complete report, maps and graphics are available online at C-CHANGE.LA/snowfall, including a password-protected media site.

The study examined snowfall in the San Gabriel Mountains, San Bernardino Mountains, San Emigdio/Tehachapi Mountains and San Jacinto Mountains. The research team scaled down low-resolution global climate models to create high-resolution models with data specific to towns such as Lake Arrowhead, Big Bear, Wrightwood and Idyllwild. Hall's team included UCLA researchers Fengpeng Sun and Scott Capps, graduate student Daniel Walton and research associate Katharine Davis Reich.

The researchers used baseline snowfall amounts from 1981 to 2000 and predicted snow amounts for midcentury (2041 to 2060) and the end of the century (2081 to 2100) under a "business as usual" scenario, in which greenhouse gas emissions increase unchecked, and a "mitigation" scenario, in which the world significantly reduces emissions. By the end of the century, the contrast between the scenarios would be dramatic. In the mitigation scenario, midcentury snow levels would be 31 percent lower than baseline, but would remain relatively steady at only 33 percent below baseline by the end of the century.

In the business-as-usual scenario, 42 percent of the snow is expected to disappear by mid-century before dwindling dramatically to a 67 percent loss of snow by the end of the century.

"The mountains won't receive nearly as much snow as they used to, and the snow they do get will not last as long," Hall said.

The snowfall study is the second part of UCLA's ongoing research project, "Climate Change in the Los Angeles Region." Through the Los Angeles Regional Collaborative for Climate Action and Sustainability, the city of Los Angeles obtained a grant from the U.S. Department of Energy to study and share climate research, with $484,166 for UCLA's climate-change studies. Additional funding came from the National Science Foundation. Future studies will cover other elements of climate change including precipitation, Santa Ana winds, soil moisture and streamflow.

The complete study, "Mid- and End-of-Century Snowfall in the Los Angeles Region," along with interactive maps and ways to get involved, is available online.

• The Los Angeles Regional Collaborative for Climate Action and Sustainability is a regional network developing the science and strategies to address climate change. Founded by the city of Los Angeles and Los Angeles County, LARC brings together leadership from government, the business community, academia, labor, and environmental and community groups to encourage greater coordination and cooperation at the local and regional levels. The goals are to share information, foster partnerships, develop system-wide strategies to address climate change, and promote a green economy. The collaborative is housed at the UCLA Institute of the Environment and Sustainability and governed by the LARC Steering Committee.
• C-CHANGE.LA serves as a clearinghouse for information about climate change and its impacts on Southern California. In 2012, C-CHANGE.LA will publish the groundbreaking studies included in the project "Climate Change in the Los Angeles Region" and provide the public with the tools to understand the scientific research and a variety of options to get involved in efforts to mitigate and adapt to climate change. C-CHANGE.LA is hosted by LARC and published by Climate Resolve, a project of Community Partners.
• UCLA is California's largest university, with an enrollment of more than 40,000 undergraduate and graduate students. The UCLA College of Letters and Science and the university's 11 professional schools feature renowned faculty and offer 337 degree programs and majors. UCLA is a national and international leader in the breadth and quality of its academic, research, health care, cultural, continuing education and athletic programs. Six alumni and six faculty have been awarded the Nobel Prize.

Contact: Alison Hewitt
310-206-5461
University of California - Los Angeles

Study of oceans' past raises worries about their future

Data from end of the last ice age illuminate the precarious nature of global ocean chemistry

The ocean the Titanic sailed through just over 100 years ago was very different from the one we swim in today. Global warming is increasing ocean temperatures and harming marine food webs. Nitrogen run-off from fertilizers is causing coastal dead zones. A McGill-led international research team has now completed the first global study of changes that occurred in a crucial component of ocean chemistry, the nitrogen cycle, at the end of the last ice age. The results of their study confirm that oceans are good at balancing the nitrogen cycle on a global scale. But the data also shows that it is a slow process that may take many centuries, or even millennia, raising worries about the effects of the scale and speed of current changes in the ocean.

"For the first time we can quantify how oceans responded to slow, natural climate warming as the world emerged from the last ice age," says Prof. Eric Galbraith from McGill University's Department of Earth and Oceanic Sciences, who led the study. "And what is clear is that there is a strong climate sensitivity in the ocean nitrogen cycle."

The nitrogen cycle is a key component of the global ocean metabolism. Like the proteins that are essential to human health, nitrogen is crucial to the health of oceans. And just as proteins are carried by the blood and circulate through the body, the nitrogen in the ocean is kept in balance by marine bacteria through a complicated cycle that keeps the ocean healthy. The phytoplankton (microscopic organisms at the base of the food chain) 'fix' nitrogen in the shallow, sunlit waters of the ocean, and then as they die and sink, nitrogen is eliminated (a process known as 'denitrification') in dark, oxygen-poor pockets of the ocean depths.

Using sediment gathered from the ocean floor in different areas of the world, the researchers were able to confirm that as the ice sheets started melting and the climate warmed up at the end of the last ice age, 18,000 years ago, the marine nitrogen cycle started to accelerate. The ocean had stabilized itself in its new, warmer state, in which the overall nitrogen cycle was running faster, by about 8,000 years ago. Given the current dramatic rate of change in the ocean nitrogen cycle the researchers are not sure how long it will take for marine ecosystems to adapt.

"We are changing the planet in ways we are not even aware of," says Galbraith. "You wouldn't think that putting carbon dioxide into the atmosphere would change the amount of nitrogen available to fish in the ocean, but it clearly does. It is important to realize just how interconnected everything is."

Citation: Galbraith, Eric D.; Kienast, Markus; "The acceleration of oceanic denitrification during deglacial warming". Nature Geoscience; DOI: 10.1038/ngeo1832

Contact: Katherine Gombay
514-398-2189
McGill University

From Botswanan big cats to Surrey house cats

Scientists who designed GPS tracking collars to study hunting cheetahs in Botswana have miniaturised them to track 50 domestic cats in a Surrey village for a BBC programme. The BBC also deployed cat-cams which were turned on by the collar's activity sensor when the cat was moving. 'The Secret Life of The Cat' is broadcast on BBC Two Horizon on Thursday June 13th 2013 at 21:00.

In a first study of its kind the wanderings of our feline friends were recorded, revealing how far they roamed and what they got up to once they leave their owners behind. The team were concerned that cats were known to pop through the cat-flaps of neighbouring houses to steal food so they used the GPS to tell when the cats were indoors and switched off the cat-cams.

Professor Alan Wilson, from the Royal Veterinary College, University of London and his team are currently studying the cheetah in research funded by the Engineering and Physical Sciences Research Council (EPSRC), Biotechnology and Biological Sciences Research Council (BBSRC), and Defence Advanced Research Projects Agency (DARPA).

Their innovative tracking collars, which use GPS and motion sensors, have recorded hunting cheetahs at a top speed of 58mph as well as the first data on the animal's acceleration and manoeuvres. The results are published in the journal, 'Nature' on Thursday June 13th 2013.

Professor Wilson said: "If we understand an animal's speed and manoeuvrability we will be able to see how managing habitats will have an impact on predators and hunting."

Back in the UK the team used their expertise to design the technology for the study on domestic cats for BBC Two's Horizon programme. They designed the protocol, programmed the collars, and analysed the data of the domestic puss.

Professor Wilson said; "Our motivation for getting involved in the programme is to showcase scientific research methods to the public and demonstrate science is cool. It's an excellent large-scale deployment opportunity for our tracking collars and the analysis tools used for our studies on wild animals. Ironically we knew more about cheetahs than domestic cats, until this study."

Reference: Locomotion dynamics of hunting in wild cheetahs; A M Wilson, J. C. Lowe, K. Roskilly, P. E. Hudson, K. A. Golabek & J. W. McNutt is published in the journal Nature.

Contact: Alan Wilson, Professor of Locomotor Biomechanics Structure and Motion Laboratory
The Royal Veterinary College, University of London

Related BBC Story: Secret life of the cat: What do our feline companions get up to?

A bird’s eye view of fishery discard reforms

Reforms to reduce discards of over-quota fish catches are generally predicted to have positive effects on marine ecosystems and biodiversity. Although concerns have been raised over the impacts of the changes on scavenging seabirds who feed upon discarded fish, new research on gannets indicates that, while they often forage near fishing vessels, more than half their time is spent foraging ‘naturally’ in the open sea.

Vast amounts of fish are discarded by commercial fishing boats, roughly 7.3 million tonnes per year worldwide, either in the form of unwanted guts or catch that has exceeded quotas. The reforms to the EU’s Common Fisheries Policy to reduce discards are therefore essential to sustainable fisheries management. Little is known, however, about how seabirds will be affected by the reduction of such an abundant source of food.

The study, partly-funded by the EU, explored whether scavenging seabirds have become completely reliant on fisheries discards, or whether they will continue to hunt for naturally-occurring prey. The researchers focused on Northern gannets habiting an island off the west coast of Britain. This is a wide-ranging seabird that is known to feed on discards from fishing boats. To gather accurate data on feeding trips, the researchers attached miniature cameras and a GPS logger to 10 birds.

The camera, fitted to the tail of each bird, recorded pictures to allow researchers to identify the presence of fishing vessels, and the GPS logger recorded the exact location of the bird. Both devices recorded data every minute. Searching behaviour, indicated by the movements of the birds, was used to identify trips searching for food, or ‘foraging bouts’.

The results revealed that 42% of the birds’ active foraging bouts occurred when a fishing vessel was present. The results also suggested a difference between male and female birds, with males more likely to forage near fishing vessels (80% of foraging bouts) than females (30%). However, the researchers do point out that the number of birds they studied was very small, so it is difficult to draw firm conclusions about this.

Overall, the fact that 58% of foraging bouts were not associated with fishing vessels suggests that gannets may be able to switch to naturally-occurring prey under a discard ban. However, the study cautions that this switch will only be successful if there is enough natural prey available, and removing discards as a source of food could have an impact on gannets. Males could be particularly affected if the patterns observed among these 10 birds are true for the wider population.

The study recommends an ecosystem-based approach to fisheries management, which takes account of all aspects of the ecosystem. This approach ensures that a range of impacts of different policies are fully understood. The researchers also highlight the value of their method to record illegal and unregulated fishing, which is extremely difficult to monitor.

Source: Votier, S. C., Bicknell, A., Cox, S. L. et al. (2013). A Bird’s Eye View of Discard Reforms: Bird-Borne Cameras Reveal Seabird/Fishery Interactions. PLoS ONE 8(3): e57376. DOI:10.1371/journal.pone.0057376.

Contact:stephen.votier@plymouth.ac.uk

Risk map shows European ‘hot spots’ for pharmaceuticals in the environment

Summed aquatic risk quotients (predicted surface water concentrations ÷ HC₅₀) due to exposure to (A) antibiotics and (B) antineoplastics. The grids with the highest summed risk quotients are accentuated with a solid black outline.

A new tool has been developed which highlights ‘hot spots’ of pharmaceutical pollution in Europe, where human health and aquatic environments could potentially be affected. The results suggest that the substances and locations posing the greatest risk are not the same for the aquatic environment as for human health.

Both the pharmaceuticals we consume, and those that we dispose of unused, are found in the environment and may potentially affect human health and ecosystems. For example, the pharmaceutical ethinyl estradiol has been found to have a feminising effect on fish in the environment. Such evidence, combined with the presence of very low levels of some pharmaceuticals in drinking water and certain foods, has also raised concerns about the potential effects of pharmaceutical pollution on humans.

The study quantified and compared the risks of pharmaceutical pollution to the aquatic environment and to human health on a regional basis in Europe. Conducted under the EU PHARMAS project, it focused on 11 common antibiotics and seven antineoplastics - a group of anti-cancer drugs.

The researchers took European pharmaceutical consumption data and estimated environmental emissions for individual countries, taking into account how many unused drugs were returned versus how many were flushed away, and how many would have been excreted into sewage systems. Sewage treatment can result in emissions via liquid effluent and from the application of sludge to agricultural land, offering another potential route of exposure as grazing animals ingest pharmaceuticals in soil and crops.

These data were used to generate a grid of emissions per 100 square kilometres, to be used as a screening tool for assessing the exposure of humans and aquatic ecosystems to pharmaceuticals on a location-by-location basis. These exposures were compared to threshold levels to produce indicative figures of risk.

Antibiotics posed a risk to aquatic environments far higher (around 1000 times) than antineoplastics, with levofloxacin, doxycycline and ciprofloxacin posing the greatest risks. Densely populated areas, such as Northern Italy, London, Krakow and the Ruhr, showed the highest levels of risk. The types of antibiotic most commonly prescribed significantly affected the environmental burden, as some are more easily broken down and toxicity varies. For example, even though the greatest number of antibiotics is prescribed in Greece, the area with the highest aquatic risk is Northern Italy, around Milan. This is because high levels of levofloxacin are used in Italy, the high population density of the Milan region, and the extreme persistence and toxicity of this antibiotic.

Risks for human health not only depend on the pharmaceutical and location, but also on behaviour, such as consumption patterns. For example, risk will be affected by whether an individual eats locally-grown food or food sourced more widely, or whether their water comes from a well, is conventionally-treated, or bottled. The main pathways for human contact with traces of pharmaceuticals from the environment are via drinking water, fruit, vegetables, meat, milk, fish, surface water and soil. Infants in eastern Spain consuming locally-produced food and conventionally-treated drinking water had the highest risk of exposure, mainly via contaminated soil, as a result of sewage sludge application to agricultural land. By contrast, infants in Paris were at relatively high risk of exposure to pharmaceuticals in water.

The researchers suggest that the study is significant because it indicates that the substances and locations posing the greatest risk are not the same for the aquatic environment as for human health, as health risks are also influenced by behaviour. This is the first tool that can be applied to prioritise pharmaceuticals, locations and exposure groups to identify hot spots for monitoring, and substances for which additional data should be gathered.

Source: Oldenkamp, R., Huijbregts, M.A.J., Hollander, A., et al. (2013) Spatially explicit prioritization of human antibiotics and antineoplastics in Europe. Environment International.
51:13-26. 

Contact:R.Oldenkamp@science.ru.nl

LIFE project removes over 30 poison threats from Italian National Park

The introduction of anti-poisoning dog units on the Italian territory by the LIFE Nature project ANTIDOTO is giving excellent results.

The project, coordinated by the Gran Sasso and Monti della Laga National Park, is centred on an innovative methodology for preventing poisoning incidents: the use of small dog units able to detect poisoned food. Three anti-poisoning dog units, two in Italy and one in Aragona (Spain), were set-up with the help of the project partner from Andalusia, which had established similar units in 2004 and has good experience in this field.

The new dog units are regularly performing field inspections, as well as inspections upon request. Results are already evident: a few days ago, during an inspection in the Italian National Park of Abruzzo, Lazio and Molise, a considerable amount of poison threats were successfully identified and removed. The threats included 29 poisoned baits and the carcasses of several poisoned animals including three foxes and two beech martens. The poisons were found by five trained dogs - three Belgian shepherds; a labrador; and a border collie – working in rough terrain with their handlers - one employee from Gran Sasso - Laga Park and one from the Italian Forest Service.

The National Park targeted is one of the most important in Italy and home to some of Europe’s endangered large carnivores. Wolves are found in the Park as well as the last remaining individuals – estimated to fewer than 50 – of the Apennine brown bear sub-population (referred to by some authors as the Marsican brown bear sub-species), which is endemic to the area. The poison could potentially have been enough to wipe out this population entirely if left in the park and had already caused the deaths of two wolves.

The hugely successful anti-poison dog units operate as part of a proposed new integrated strategy for preserving the target carnivore and raptor species in areas of Italy and Spain.

Warm ocean drives most Antarctic ice shelf loss

Findings are a game changer for future forecasts about thawing continent

Aerial photo of front of Venable Ice Shelf, West Antarctica, an example of a small ice shelf that is a large meltwater producer. Such ice melts are far more common than previously thought and will change predictions about the thawing continent. Taken onboard the Chilean Navy P3 aircraft during the NASA/Centro de Estudios Cientificos fall 2008 campaign.

Ocean waters melting the undersides of Antarctic ice shelves, not icebergs calving into the sea, are responsible for most of the continent's ice loss, a study by UC Irvine and others has found.

The first comprehensive survey of all Antarctic ice shelves discovered that basal melt, or ice dissolving from underneath, accounted for 55 percent of shelf loss from 2003 to 2008 – a rate much higher than previously thought. Ice shelves, floating extensions of glaciers, fringe 75 percent of the vast, frozen continent.

The findings, to be published in the June 14 issue of Science, will help scientists improve projections of how Antarctica, which holds about 60 percent of the planet's freshwater locked in its massive ice sheet, will respond to a warming ocean and contribute to sea level rise.

It turns out that the tug of seawaters just above the freezing point matters more than the breaking off of bergs.

"We find that iceberg calving is not the dominant process of ice removal. In fact, ice shelves mostly melt from the bottom before they even form icebergs," said lead author Eric Rignot, a UC Irvine professor who's also a researcher with NASA's Jet Propulsion Laboratory in Pasadena. "This has profound implications for our understanding of interactions between Antarctica and climate change. It basically puts the Southern Ocean up front as the most significant control on the evolution of the polar ice sheet."

Ice shelves grow through a combination of land ice flowing to the sea and snow falling on their surfaces. The researchers combined a regional snow accumulation model and a new map of Antarctica's bedrock with ice shelf thickness, elevation and velocity data captured by Operation IceBridge – an ongoing NASA aerial survey of Greenland and the South Pole. (Rignot will host a planning session of Operation IceBridge scientists at UC Irvine on June 17 and 18.)

Ocean melting is distributed unevenly around the continent. The three giant ice shelves of Ross, Filchner and Ronne, which make up two-thirds of Antarctica's ice shelves, accounted for only 15 percent. Meanwhile, less than a dozen small ice shelves floating on relatively warm waters produced half the total meltwater during the same period.

The researchers also compared the rates at which the ice shelves are shedding ice with the speed at which the continent itself is losing mass and found that, on average, the shelves lost mass twice as fast as the Antarctic ice sheet did.

"Ice shelf melt can be compensated by ice flow from the continent," Rignot said. "But in a number of places around Antarctica, they are melting too fast, and as a consequence, glaciers and the entire continent are changing."

Other authors are Jeremie Mouginot and Bernd Scheuchl of UC Irvine and Stanley Jacobs of Columbia University. Funding was provided by NASA, the National Science Foundation, and the National Oceanic & Atmospheric Administration.

Contact: Janet Wilson
949-824-3969
University of California - Irvine

Study shows how diving mammals evolved underwater endurance

Photo credit: J. Burns

Scientists at the University of Liverpool have shed new light on how diving mammals, such as the sperm whale, have evolved to survive for long periods underwater without breathing.

The team identified a distinctive molecular signature of the oxygen-binding protein myoglobin in the sperm whale and other diving mammals, which allowed them to trace the evolution of the muscle oxygen stores in more than 100 mammalian species, including their fossil ancestors.

Myoglobin, which gives meat its red colour, is present in high concentrations in elite mammalian divers, so high that the muscle is almost black in colour. Until now, however, very little was known about how this molecule is adapted in champion divers.

Proteins tend to stick together at high concentrations, impairing their function, so it was unclear how myoglobin was able to help the body store enough oxygen to allow mammals, such as whales and seals, to endure underwater for long periods of time without breathing. Elite mammalian divers can hold their breath for over an hour while they hunt in the depths of the oceans, while land mammals, such as humans, can hold their breath for only a few minutes.

Dr Michael Berenbrink, from the University's Institute of Integrative Biology, who led the international team, explains: "We studied the electrical charge on the surface of myoglobin and found that it increased in mammals that can dive underwater for long periods of time. We were surprised when we saw the same molecular signature in whales and seals, but also in semi-aquatic beavers, muskrats and even water shrews.

"By mapping this molecular signature onto the family tree of mammals, we were able to reconstruct the muscle oxygen stores in extinct ancestors of today's diving mammals. We were even able to report the first evidence of a common amphibious ancestor of modern sea cows, hyraxes and elephants that lived in shallow African waters some 65 million years ago."

Dr Scott Mirceta, PhD student on the project, added: "Our study suggests that the increased electrical charge of myoglobin in mammals that have high concentrations of this protein causes electro-repulsion, like similar poles of two magnets. This should prevent the proteins from sticking together and allow much higher concentrations of the oxygen-storing myoglobin in the muscles of these divers."

"We are really excited by this new find, because it allows us to align the anatomical changes that occurred during the land-to-water transitions of mammals with their actual physiological diving capacity. This is important for understanding the prey items that were available to these extinct animals and their overall importance for past aquatic ecosystems."

The research, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), could also help improve understanding of a number of human diseases where protein aggregation is a problem, such as Alzheimer's and diabetes, and could inform the development of artificial blood substitutes.

Dr Berenbrink added: "This finding illustrates the strength of combining molecular, physiological and evolutionary approaches to biological problems and, for the first time, allows us to put 'flesh' onto the bones of these long extinct divers."

The research, in collaboration with the University of Manitoba, Canada, and the University of Alaska,US, is published in Science.

Contact: Samantha Martin
44-015-179-42248
University of Liverpool

Oysters could rebound more quickly with limited fishing and improved habitat

Fox Island Environmental Education Center

Fox Island Environmental Education Center

Fox Island Environmental Education Center

Fox Island Environmental Education Centre.

A new study shows that combining improved oyster restoration methods with limits on fishing in the upper Chesapeake could bring the oyster population back to the Bay in a much shorter period of time. The study led by Michael Wilberg of the University of Maryland Center for Environmental Science's Chesapeake Biological Laboratory assessed a range of management and restoration options to see which ones would have the most likelihood success.

"This new model we developed suggests that oysters should be able to come back if we help them out by reducing fishing pressure and improving their habitat," said Wilberg.

Eastern oysters in the Chesapeake Bay have undergone a drastic decrease in abundance over the past century due to overfishing and disease. The population is currently estimated to be less than one percent of its historic high, making substantial restoration efforts necessary if the population is to recover.

The team's study shows that if oysters were allowed to reproduce naturally and fishing were halted, it would take between 50 to 100 years for oyster abundance to reach as high a level as could be supported by the Bay. If fishing were reduced to about half its current level, it would take as many as 200 to 500 years to see a healthy population restored to the Bay.

Maryland Seafood

"The fishery as it has been practiced hasn't been sustainable, and our model helps explain why," said Wilberg. "Oysters just can't replace the shell that has been removed fast enough to keep up."

Oysters are called ecosystem engineers because they build habitat for themselves and other creatures. Oyster harvesting methods, such as dredging and tonging, chip away at the oyster reef and knock it down, spreading the shells over the bottom and making the remaining oysters prone to being covered by silt or moving them to a soft surface where oysters cannot grow.

Since reefs are the place where oysters are born and reproduce, fishing not only removes adults from the population, but also removes habitat essential to their survival.

"Oysters should be able to rebuild their reefs if we leave them alone," said Wilberg. "It's an experiment that hasn't been tried yet."

The study, Sustainable exploitation and management of autogenic ecosystem engineers: application to oysters in Chesapeake Bay appears in the June issue of Ecological Applications.

Contact: Amy Pelsinsky
410-313-8808
University of Maryland Center for Environmental Science

World population could be nearly 11 billion by 2100, UW research shows

The expected population changes from now to 2100 are shown in the graphic. By far the largest expected increase is in Nigeria, projected to increase by 730 million people, from 184 million now to 914 million in 2100. Eight of the top ten increases are in Africa, with India in second place. The United States is eighth, with an expected increase of 146 million, or 46 percent, from 316 million now to 462 million in 2100. The largest projected decline is in China, expected to decrease by about 300 million, from 1.4 billion now to 1.1 billion in 2100.

A new statistical analysis shows the world population could reach nearly 11 billion by the end of the century, according to a United Nations report issued June 13. That's about 800 million, or about 8 percent, more than the previous projection of 10.1 billion, issued in 2011.

The projected rise is mostly due to fertility in Africa, where the U.N. had expected birth rates to decline more quickly than they have.

"The fertility decline in Africa has slowed down or stalled to a larger extent than we previously predicted, and as a result the African population will go up," said Adrian Raftery, a University of Washington professor of statistics and of sociology.

The current African population is about 1.1 billion and it is now expected to reach 4.2 billion, nearly a fourfold increase, by 2100.

The new U.N. estimates use statistical methods developed by Raftery and his colleagues at the UW Center for Statistics and the Social Sciences. The group's improved fertility forecasting methods, combined with updated data collected by the U.N., were used to project the long-term consequences of the fertility change in Africa since the last population estimate two years ago.

New to this year's projection are finer-tuned statistics that anticipate the life expectancies of women and men across this century.

In other areas of the world, fewer major population changes are expected. Europe may see a small decline because of fertility continuing below replacement level, and other nations around the globe may see modest increases due to longer life expectancies, Raftery said.

There's no end in sight for the increase of world population, he added, yet the topic has gone off the world's agenda in favor of other pressing global issues, including poverty and climate – both of which have ties to world population.

"These new findings show that we need to renew policies, such as increasing access to family planning and expanding education for girls, to address rapid population growth in Africa," Raftery said.

The UN gives high and low variants of its projections, assuming that women have an average of half a child more or less than the best projection. That leaves a large uncertainty, from 7 billion to nearly 17 billion, in the range for potential world population by the end of this century.

By contrast, the UW research group has developed probabilities of future population levels to be coupled with best forecasts. "Our probability intervals are much tighter, ranging from 9 billion to 13 billion in 2100," Raftery said.

Global population reached 7 billion in 2011. It passed 6 billion in 1999.

Contact: Vince Stricherz
206-543-2580
University of Washington

France and IUCN intensity their efforts to protect global biodiversity

Delphine Batho, Minister of Ecology, Sustainable Development and Energy, France.

Yesterday IUCN signed a new partnership agreement with France, which aims to support the Union's global biodiversity conservation work, focusing on sub-Saharan Africa, oceans and global governance of natural resources.

Delphine Batho, Minister of Ecology, Sustainable Development and Energy, Victorin Lurel, Minister of Overseas France, Pascal Canfin, Deputy Minister for Development and Anne Paugam, CEO of the French Development Agency signed the agreement with IUCN, represented by Julia Marton-Lefèvre, its Director General. The partnership aims to bring significant progress in biodiversity conservation that is expected to be achieved by 2016.

Initially signed in 2005 and renewed in 2009, the partnership agreement between France and IUCN has thus been extended for another four years, thereby strengthening France's commitment to protecting biodiversity, in accordance with its international engagements regarding the Convention for Biological Diversity (CBD).

France will invest almost 8 million Euros in order to support actions in three major areas aimed at protecting global biodiversity:

• The conservation of biodiversity and the sustainable management of natural resources in sub-Saharan Africa;
• The governance of the Oceans and the protection of the marine environment in developing coastal and insular territories in EU overseas entities;
• Global biodiversity governance.

With the signing of this agreement, France reinforces its position as one of IUCN’s strategic partners. An organization that was founded in Fontainebleau in 1948, IUCN brings together over 1,200 members - government organisations (including 92 states) and non-government organisations – and 11,000 scientists and experts worldwide.

Nouvelle Caledonie

“With regard to biodiversity, France considers it has a particular responsibility, due to the great diversity of its natural heritage, its overseas territories and its marine areas," said Delphine Batho, Minister of Ecology, Sustainable Development and Energy at the signing ceremony in Paris. "IUCN is carrying out essential work, exploring new areas that need to be monitored and protected. This agreement will help give substance to the priority France gives to the issue of the oceans, and to European and international commitments regarding marine biodiversity. The future of humanity is linked to that of biodiversity. It is simply a matter of protecting all living beings - protecting our living planet”.

“Responding to the current crisis regarding nature on the African continent, ensuring better protection for the oceans and providing scientific knowledge to support the global governance of natural resources – these are the central themes of this new partnership between France and IUCN, said Julia Marton-Lefèvre, IUCN Director General. "I am very happy that we are going to intensify our joint efforts to prove that nature is a source of solutions to global issues such as climate change, poverty, and food and energy security,” 

“Thanks to its overseas territories, France is unique in that it is present on all continents except Asia, and in all the oceans," said Victorin Lurel, Minster of Overseas France. "Thus, it has a unique responsibility regarding the protection and sustainable management of biodiversity. Due to their insular nature, France’s overseas territories present specific features in terms of richness of their biodiversity, extremely high level of endemism, and also in terms of their fragility and the threats they face, including global climate change. IUCN’s mission is to influence, encourage and assist societies throughout the world to conserve the integrity and diversity of nature, and to ensure that any use of natural resources is equitable and ecologically sustainable. Moreover, it benefits from an international network, which brings together over 1,200 members, from both the private and the public sectors. These characteristics clearly make IUCN a natural and privileged partner of the French Government in the consolidation of its political commitment to the protection of biodiversity.”

“The protection of biodiversity is, along with the climate, a fundamental issue for sustainable development, said Pascal Canfin, Deputy Minister for Development. "The growth of the world’s urban population, the intensive use of natural resources and the degradation of ecosystems and land threaten food and health security, above all affecting the poorest people in society. This situation is particularly serious in Africa. The French Development Agency (AFD) is about to publish its first biodiversity intervention strategy. Within this context, AFD plans to double its funding, which should reach 600 million Euros over the next four years. IUCN is an ideal partner for taking up this challenge.”

Contact: Ewa Magiera, IUCN 

DNA sequencing uncovers secrets of white cliffs of Dover

White Cliffs of Dover.

The University of Exeter recently contributed to a major international project to sequence the genome of Emiliania huxleyi, the microscopic plankton species whose chalky skeletons form the iconic white cliffs of Dover. The results of the project are published this week in the journal Nature.

Emiliania huxleyi is one of the most abundant marine phytoplankton species and is a key player in the process of CO2 exchange between the atmosphere and the ocean. In some marine systems 20% of the total carbon is fixed by E. huxleyi. This microscopic alga has influenced the global climate for over 200 million years, so is used as a model system for studying how physical, chemical and biological processes regulate the Earth's systems. The algae form pale chalky cases called coccoliths which during the spring bloom can be seen from space in the seas around the UK. E. huxleyi directly links to climate change through the production of dimethylsulfide (DMS), which induces cloud formation and blocks solar radiation.

Thanks to new technology – next generation DNA sequencing – 13 different isolates were sequenced from around the world, and compared to a complete sequence constructed for E. huxleyi strain CCMP1516. The allowed the team to understand the influences of different environmental conditions on E. huxleyi physiology. The international team found that E. huxleyi possess a higher number of genes than previously published marine phytoplankton genomes, and that most genes were present in multiple copies.

Dr Mark Van Der Giezen from the University of Exeter said: "Using comprehensive analysis to compare different strains of the algae, we demonstrated that E. huxleyi should no longer be considered a single species. Substantial variation in the genome indicates contrasting metabolic composition and supports the idea that E. huxleyi is a species complex."

Comparing patterns, or phylogenetic relationships, in the genomes of the different strains identified three groups which did not relate to geographic origin nor genome size. Further research into the genomes revealed that the E. huxleyi genome includes core regions shared by all samples with some variable elements. Regions with high levels of tandem repeats and low complexity may have allowed rapid evolutionary adaptation over many millions of years, allowing current strains to live in a range of light conditions.

The study of the E. huxleyi genome shows many unexpected features that may be unique or common in microalgae warranting further investigation. For example, metabolic pathways, known previously only in fungi and animals that allow lipid synthesis were found. Using this new insight into an age-old algae, there is future potential for E. huxleyi to be used to synthesise nutritional supplements, biofuels, feedstock and polymer precursors, which may make E. huxleyi a valuable species for cutting-edge biotechnology.

Contact: Jo Bowler
44-013-927-22062
University of Exeter

'Tailing' spiny lobster larvae to protect them

New tools track planktonic larvae, offer possible solutions to safeguard this $1 billion industry

Panulirus argus. Credit: NOAA

The commercial value of spiny lobster (Panulirus argus) in the Caribbean reaches $1 billion annually, thus making it one of the most valuable fisheries in the region. In a new study of this iconic species, Ph.D. candidate Andrew Kough and Dr. Claire Paris of the Biophysical Interactions Lab at the University of Miami Rosenstiel School of Marine & Atmospheric Science, in collaboration with Dr. Mark Butler from Old Dominion University, studied the larval dispersal of this species in the Caribbean. The goal of the study was to describe the sources, sinks, and routes connecting the Caribbean spiny lobster metapopulation. The results led the team to propose marine resource management strategies that incorporate larval connectivity and "larval lobster credits" to sustain and rebuild exploited marine populations.

The study, which appears in the June 2013 issue of the journal PLOS ONE, synthesizes empirical data from laboratory studies, mail surveys and published works to parameterize an individual-based model of lobster larval connectivity, the Connectivity Modeling System (CMS), developed by Paris. Results were then verified using two independent studies, separated by over 500 km, giving validation to the model's performance -- something never before achieved for spiny lobster or other pelagic larvae over such large scales.

"Spiny lobster have extraordinary larvae with a prolonged planktonic existence that can last from five months to nearly a year, which confer them with high dispersal potential and complex pelagic pathways. Despite such challenges in documenting their pathways in the open ocean, just like hurricane models that help to reduce the 'cone of uncertainty', in this case we are improving settlement predictions by simulating large numbers of spawning events and tracking virtual larvae undergoing deep vertical migrations," says Paris.

The prevailing Caribbean current may not be the best path for successful long distance transportation for larvae. Contrary to the established belief, the team's results suggest that powerful currents entrain and push larvae out of the system, acting like a "Highway to Hell." The larvae that ultimately settle in the simulation spend little time within these strong currents. By moving to deeper depths as they age, spiny lobster larvae seem to increase their odds of settlement.

Butler adds, "Despite some expected degree of ocean mixing in the region, we found relatively high levels of larvae settling back to their place of origin. This was surprising for larvae that spend up to 12 months traveling in the plankton. But even more surprising was that these simple larval behaviors added to the model also enhanced population connectivity by preventing larvae from being flushed out of the system."

Based on the dynamics of long distance larval exchange uncovered using this computational model, the team proposes potential strategies that may be used to better manage the Caribbean spiny lobster population, and increase the sustainability of this economically important fishery.

"We blended ideas from international trade, terrestrial conservation, and carbon emission protocols to suggest 'larval lobster credits' as a viable cooperative management strategy. Predicted larval flow around in the region is dependent on several source regions, which are optimally located for wide ranging dispersal. If the nations receiving the influx of larvae and harvesting the adult lobsters were to invest and help protect these source regions, we believe that the future of the fishery will be more secure and may even improve, which would benefit the entire region ecologically and economically," explains Kough.

Citation: Kough AS, Paris CB, Butler MJ IV (2013) Larval Connectivity and the International Management of Fisheries. PLoS ONE 8(6): e64970. doi:10.1371/journal.pone.0064970

Contact: Barbra Gonzalez
University of Miami Rosenstiel School of Marine & Atmospheric Science

Rapid adaptation is purple sea urchins' weapon against ocean acidification

The purple sea urchin, Strongylocentrotus purpuratus. Credit: Gretchen Hofmann

In the race against climate change and ocean acidification, some sea urchins may still have a few tricks up their spiny sleeves, suggesting that adaptation will likely play a large role for the sea creatures as the carbon content of the ocean increases.

"What we want to know is, given that this is a process that happens over time, can marine animals adapt? Could evolution come to the rescue?" said postdoctoral researcher Morgan Kelly, from UC Santa Barbara's Department of Ecology, Evolution and Marine Biology. She is a co-author of the paper "Natural variation, and the capacity to adapt to ocean acidification in the keystone sea urchin Strongylocentrotus purpuratus." The paper was published in the latest edition of the journal Global Change Biology.

Easily identified by their spherical symmetry and prickly barbs, sea urchins are found on the sea floor all over the world. They are considered a keystone species, meaning their population has an important impact on the rest of the undersea ecosystem. Too many of them and their habitat becomes barren and other algae-eating species disappear; too few and their predators –– including sea mammals, seabirds, and fish –– lose an important food source.

Due to rising carbon dioxide in the Earth's atmosphere, the oceans of the future are projected to absorb more carbon dioxide, leading to acidification of the water. The change in the ocean chemistry is expected to negatively affect the way urchins and other calcifying creatures create and maintain their shells and exoskeletons.

"It gives them osteoporosis," said Kelly. Increased water acidity would cause the levels of calcium carbonate –– which the sea urchins require –– to decrease. This, in turn, would result in smaller animals, thinner shells and perhaps shorter spines for the urchins.

To observe the potential effects of future increased levels of carbon dioxide in ocean water, the researchers bred generations of purple sea urchins in conditions mimicking projected environment of the ocean in near the end of the century.

"We exposed them to 1,100 parts per million of carbon dioxide," Kelly said. Current CO₂ levels top off at about 400 parts per million and the levels are expected to increase globally to 700 parts per million by the end of the century. In the California region, however, CO₂ levels in the ocean naturally fluctuate because of cold water upwelling, a phenomenon that also brings more acidic waters.

UCSB Researcher Morgan Kelly. In her hands is a red urchin, close relative of the purple urchin, and one of several marine species being studied in the Hofmann lab for their response to ocean acidification. The other species include coral, algae, and the California mussel.

The animals were taken from two locations off the California coast –– a northern site, which experiences greater upwelling, and a southern site that experiences shorter, less frequent bouts of upwelling. Males from one site were crossed with females from the other site. The larvae were spawned and observed in the projected conditions of the future oceans.

While the larvae reared under the future carbon dioxide levels were, on average, smaller, the researchers also noted a wide variation in size, indicating that some of these larvae –– the ones that remained the same size as they would have under today's conditions –– had inherited a tolerance for higher CO₂ levels. Size, said Kelly, is an important trait. It's tied to feeding rate and the risk of being eaten by other creatures. The animals that can withstand higher CO₂ levels in the ocean will leave more offspring than their weaker counterparts. This natural selection, coupled with the finding that variation in size under more acidic conditions is heritable, points to the rapid evolution of the purple urchin.

"This is what allows us to predict that this species will evolve increased tolerance –– as CO₂ rises, urchins that have greater tolerance will have a better chance of survival, and they will pass on their greater tolerance to their offspring," said Kelly.

The findings suggest that the effects of ocean acidification may not have as deleterious an impact on sea urchin size or population growth rates as previously thought. Good news for the keystone species, and good news for the creatures that eat them. The results also suggest that adaptation is a major factor in the response of ecologically important species to climate change.

"We don't expect evolution to completely erase the effects of ocean acidification, but we do expect evolution to mitigate these effects. And the more heritable variation there is, the greater the power of evolution to mitigate the effects of climate change," said Kelly.

Research for this study was also conducted by postdoctoral researcher Jacqueline Padilla-Gamiño, and Gretchen Hofmann, professor in the Department of Ecology, Evolution and Marine Biology. Similar CO₂ studies are being conducted on other marine species in the Hofmann lab, including red urchin, coral, algae, and the California mussel.

Contact: Sonia Fernandez
805-893-4765
University of California - Santa Barbara