Ecology, Climate Change and Related News

Conservation Science for a Healthy Planet

Category Archive: Ecology

  1. World’s biggest fisheries supported by seagrass meadows

    Leave a Comment
    • Seagrass meadows help to support world fisheries productivity
    • “The chasm that exists between coastal habitat conservation and fisheries management needs to be filled to maximise the chances of seagrass meadows supporting fisheries, so that they can continue to support human wellbeing”
    May 21, 2018 Swansea University Read full ScienceDaily article here
    “Scientific research has provided the first quantitative global evidence of the significant role that seagrass meadows play in supporting world fisheries productivity… The study provides evidence that a fifth of the world’s biggest fisheries, such as Atlantic Cod and Walleye Pollock are reliant on healthy seagrass meadows. The study also demonstrates the prevalence of seagrass associated fishing globally….

    ….Dr Unsworth said: “The coastal distribution of seagrass means it is vulnerable to a multitude of both land and sea based threats, such as land runoff, coastal development, boat damage and trawling. There is a global rapid decline of seagrass and when seagrass is lost there is strong evidence globally that fisheries and their stocks often become compromised with profound negative economic consequences. To make a change, awareness of seagrasses role in global fisheries production must pervade the policy sphere. We urge that seagrass requires targeted management to maintain and maximise their role in global fisheries production.”

    Richard K.F. Unsworth, Lina Mtwana Nordlund, Leanne C. Cullen-Unsworth. Seagrass meadows support global fisheries production. Conservation Letters, 2018; e12566 DOI: 10.1111/conl.12566

  2. Tree die-offs in CA can harm trees on the opposite coast

    Leave a Comment
    • If a whole forest disappears, new research shows, this has ricocheting effects in the atmosphere that affect vegetation on the other side of the country.
    • The Pacific Southwest region, which covers most of California, has the smallest total area of tree cover. But removing those trees had the biggest influence on growing conditions nationally, by reducing vegetation in the Eastern U.S.
    • Forest loss is disrupting or changing the flow patterns in the atmosphere that is leading to a slightly different summertime climate in the eastern part of the country.

    May 16, 2018 University of Washington Read full ScienceDaily article here

    Large swaths of U.S. forests are vulnerable to drought, forest fires and disease. Many local impacts of forest loss are well known: drier soils, stronger winds, increased erosion, loss of shade and habitat. But if a whole forest disappears, new research shows, this has ricocheting effects in the atmosphere that can affect vegetation on the other side of the country.

    ….forest die-offs in specific regions of the United States can influence plant growth in other parts of the country. The largest impacts seen were from losing forest cover in California, a region that is currently experiencing dramatic tree mortality.

    “These smaller areas of forest can have continental-scale impacts, and we really need to be considering this when we’re thinking about ecological changes,” said first author Abigail Swann, a UW assistant professor of atmospheric sciences and of biology. Such far-off effects are accepted in the atmospheric sciences community, Swann said, but the idea is only beginning to be accepted by ecologists….

    “Forest loss is disrupting or changing the flow patterns in the atmosphere that is leading to a slightly different summertime climate in the eastern part of the country,” Swann said. “It’s very analogous to El Niño or ‘the blob,’ something that’s occurring that causes the atmosphere to move around, which causes these warmer or cooler conditions, or wetter and drier conditions, somewhere else.”…

    …The study suggests that current forest loss in Western regions is big enough to trigger changes in plant growth, though it might not be possible to detect these small changes over large areas of the country…

    Abigail L S Swann, Marysa M Laguë, Elizabeth S Garcia, Jason P Field, David D Breshears, David J P Moore, Scott R Saleska, Scott C Stark, Juan Camilo Villegas, Darin J Law, David M Minor. Continental-scale consequences of tree die-offs in North America: identifying where forest loss matters most. Environmental Research Letters, 2018; 13 (5): 055014 DOI: 10.1088/1748-9326/aaba0f

  3. Mixed forests: Ecologically and economically superior around the globe

    Leave a Comment
    • Meta-analysis provides facts on mixed-species forest stand productivity for science and practice
    May 9, 2018 Technical University of Munich (TUM)
    Mixed forests are more productive than monocultures. This is true on all five continents, and particularly in regions with high precipitation. These findings are highly relevant for forest science and forest management on a global scale….

    …This meta-analysis and overview study now shows that a prudent selection of the combination of tree species leads not only to more ecological and resilient forests, but also to greater productivity, explains Pretzsch. The study documents that mixed stands perform better in terms of productivity than monocultures, particularly in areas with favorable water supplies, such as in Central Europe….

    H. Jactel, E. S. Gritti, L. Drössler, D. I. Forrester, W. L. Mason, X. Morin, H. Pretzsch, B. Castagneyrol. Positive biodiversity–productivity relationships in forests: climate matters. Biology Letters, 2018; 14 (4): 20170747 DOI: 10.1098/rsbl.2017.0747
  4. Rising emissions of ozone-destroying chemical banned by Montreal Protocol

    Leave a Comment
    • A new study documents an unexpected increase in emissions of CFC-11, likely from new, unreported production.
    • Measurements from Hawaii indicate the sources of the increasing emissions are likely in eastern Asia.

    May 16, 2018 University of Colorado at Boulder  Read full ScienceDaily article here

    Emissions of one of the chemicals most responsible for the Antarctic ozone hole are on the rise, despite an international treaty that required an end to its production in 2010, a new study shows.

    Trichlorofluoromethane, or CFC-11, is the second-most abundant ozone-depleting gas in the atmosphere and a member of the family of chemicals most responsible for the giant hole in the ozone layer that forms over Antarctica each September. Once widely used as a foaming agent, production of CFC-11 was phased out by the Montreal Protocol in 2010.

    …These findings represent the first time emissions of one of the three most abundant, long-lived CFCs have increased for a sustained period since production controls took effect in the late 1980s.

    If the source of these emissions can be identified and mitigated soon, the damage to the ozone layer should be minor. If not remedied soon, however, substantial delays in ozone layer recovery could be expected, Montzka said….

    Stephen A. Montzka et al. An unexpected and persistent increase in global emissions of ozone-depleting CFC-11. Nature, 2018; 557 (7705): 413 DOI: 10.1038/s41586-018-0106-2

  5. Shorebirds, the world’s greatest travelers, face extinction

    Leave a Comment

    By John W. Fitzpatrick and Nathan R. Senner  April 27 2018  See full NYTimes Opinion article here

    Dr. Fitzpatrick is director of the Cornell Laboratory of Ornithology. Dr. Senner is a scientist who studies migratory shorebirds.

    A worldwide catastrophe is underway among an extraordinary group of birds — the marathon migrants we know as shorebirds. Numbers of some species are falling so quickly that many biologists fear an imminent planet-wide wave of extinctions.

    These declines represent the No. 1 conservation crisis facing birds in the world today. Climate change, coastal development, the destruction of wetlands and hunting are all culprits. And because these birds depend for their survival, as we do, on the shorelines of oceans, estuaries, rivers, lakes, lagoons and marshes, their declines point to a systemic crisis that demands our attention, for our own good.

    No doubt you’ve seen some of these birds while on vacation at the beach, skittering back and forth along the cusp of waves as they peck with their long beaks for tiny sand flies or the eggs of horseshoe crabs. They can seem comic in their frenetic exertions, tiny Charlie Chaplins in bird suits.

    But these birds are remarkable in ways that defy not only belief but scientific understanding: They are, by far, the planet’s most extraordinary global travelers. Worldwide, about 70 shorebird species travel from the top of the world to its very bottom and back each year. The smallest weigh barely an ounce. Each species has its own story, but in every case these annual migrations are among nature’s most epic dramas….

    ….Shorebirds also require safe passage. Here again, there’s progress. Several years ago, two whimbrels being tracked via a satellite transmitter somehow survived a harrowing migratory flight through Hurricane Irene, only to be shot by bird hunters shortly after touching down for a rest in the West Indies. Afterwards, hunting of certain shorebirds was limited or banned by French-governed Guadeloupe and Martinique, and neighboring Barbados. In China, officials began enforcing no-hunting laws following a television news exposé about illegal bird netting.

    These are promising first steps but we need to do more, fast, for our own good. Hurrricane Sandy was a reminder that natural seacoasts are good not just for shorebirds but also for humans, serving as buffers against powerful waves and storm surges. Damage from the storm was especially severe where natural shoreline habitats had been sacrificed to buildings.

    The global collapse of migratory shorebird populations is much more than a calamity facing a group of exquisitely evolved birds. It also tells us that our global network of aquatic systems is fraying. If water is the world’s lifeblood and aquatic systems are its connective tissue, then the decline of the planet’s most spectacular global travelers signals a systemic illness that demands our attention and action.

     

    Each spring, for instance, Hudsonian godwits depart from the southernmost coastlines of South America and fly north more than 9,000 miles to breed in the Arctic. Most make just one stop on the way — perhaps at a rice field in East Texas or a prairie wetland in South Dakota.

    Outclassing Hudsonian godwits in long-distance travel are their close cousins, the bar-tailed godwits. Weighing barely a pound, they have made the longest continuous flights ever recorded for a bird. Individuals tracked by satellite have traveled nonstop more than 7,000 miles, flying for nine days over the Pacific Ocean between Alaska and New Zealand. To do this, a godwit must eat voraciously before flight. By liftoff day, it will have doubled in size, half its body weight a gas tank of fat.

    Migrating godwits fly continuously through dark of night, buffeting winds and swirling storms, guided only by neural capacities packed into a hazelnut-size brain. To navigate, they may rely on sun and star alignments, a sense of the earth’s magnetic field and perhaps even a map in their brain of the entire Pacific, with its far-flung tiny islands representing visual way points.

  6. Beaver dams reduce soil loss and trap pollutants

    Leave a Comment
    • Researchers found that beaver dams trapped more than 100 tonnes of sediment, 70% of which was soil, which had eroded from ‘intensively managed grassland’ fields upstream.
    • This sediment contained high concentrations of nitrogen and phosphorus, which are nutrients known to create problems for the wildlife in rivers and streams and which also need to be removed from human water supplies to meet drinking-quality standards.

    May 9, 2018 University of Exeter Read full ScienceDaily article here

    Beavers could help clean up polluted rivers and stem the loss of valuable soils from farms, new research shows.

    …”we are heartened to discover that beaver dams can go a long way to mitigate this soil loss and also trap pollutants which lead to the degradation of our water bodies. Were beaver dams to be commonplace in the landscape we would no doubt see these effects delivering multiple benefits across whole ecosystems, as they do elsewhere around the world.”

    …”Our partnership with Exeter University working on both our fenced and unfenced beaver trials is revealing information which shows the critical role beavers can play, not only for wildlife, but the future sustainability of our land and water. It is truly inspiring to have our observations confirmed by detailed scientific investigations.”

    Alan Puttock, Hugh A. Graham, Donna Carless, Richard E. Brazier. Sediment and Nutrient Storage in a Beaver Engineered Wetland. Earth Surface Processes and Landforms, 2018; DOI: 10.1002/esp.4398

  7. Big fish produce disproportionately more and bigger eggs; need to reduce fishing pressure on larger fish to maintain stocks

    Leave a Comment
    • Taking a single big fish has a bigger impact on the fish population than taking multiple small ones.

    May 10, 2018 Smithsonian Tropical Research Institute read full ScienceDaily article here

    Contrary to prevailing dogma, plus-sized female fish invest disproportionately more in making eggs than smaller females. Therefore, taking a single big fish has a bigger impact on the fish population than taking multiple small ones…

    ….[Our results] tell us to reduce fishing pressure on large fish rather than smaller ones in order to maintain and replenish stocks,” said staff scientist D. Ross Robertson at the Smithsonian Tropical Research Institute (STRI) in Panama. “We need to focus on reducing fishing pressure on large fish rather than exploiting them more heavily than small fish.”…

    “….fecundity in marine fish [being] non-linear is important not only for managing commercial fish stocks to maintain and enhance their productivity, but also for understanding evolution and for managing invasive species such as lionfish, in which the big females seem to be concentrated in deep water,” said Robertson.

    Diego R. Barneche, D. Ross Robertson, Craig R. White, Dustin J. Marshall. Fish reproductive-energy output increases disproportionately with body size. Science, 2018; 360 (6389): 642 DOI: 10.1126/science.aao6868

     

     

  8. Impacts of windfarm construction noise on harbor porpoises

    Leave a Comment
    • Researchers demonstrate how the framework can be used for spatial planning to partly mitigate population impacts of disturbances.

    May 7 2018 Read full ScienceDaily article here

    Scientists from Germany, Denmark and the UK have built a model tool to predict what happens to marine animals when exposed to noise from the construction and operation of windfarms at sea. Using the North Sea harbor porpoise (Phocoena phocoena) population as a case study, they demonstrate how the model can be used to evaluate the impact of offshore wind farm construction noise.

    This type of noise is increasingly prevalent due to the high demand for green energy, and currently there are >900 offshore wind farms at various stages of development in Europe alone. Porpoises are strictly protected in European waters, so assessing the impacts of construction noise is critical for regulators. We demonstrate how the framework can be used for spatial planning to partly mitigate population impacts of disturbances….

    Jacob Nabe-Nielsen, Floris M van Beest, Volker Grimm, Richard M Sibly, Jonas Teilmann, Paul M Thompson. Predicting the impacts of anthropogenic disturbances on marine populations. Conservation Letters, 2018; e12563 DOI: 10.1111/conl.12563

  9. Land-use change interacts with climate to determine species redistribution

    Leave a Comment
    • How species respond to both habitat loss and changing climates should be considered carefully for effective conservation and management of biodiversity.
    • Some species may be able to move (and do move) in response to climate change and/or land-use change. Those species that are unable to respond effectively to warming or habitat loss face a high risk of extinction.
    • The results show that tropical species may be especially vulnerable to the dual effects of climate and land-use changes.

    May 7, 2018 The University of Hong Kong Read ScienceDaily article here

    Climate change is altering where species live all over the planet. With global warming, species are moving towards the poles and up elevation where temperature is lower. However, along with global climate change, the world is also experiencing massive changes in land use which may also impact where species live. Could both of these forces be influencing current changes in species distributions?

    …Increasing documentation of evidence for species redistribution under climate change in recent years made this research possible. “While the importance of land-use change for climate-driven species shifts has long been recognized, how land-use change is important or to what extent it affects species redistribution was never fully appreciated” noted Miss Guo. “Most of the studies we reviewed in this work stated that land-use remained unchanged over time while the data suggested otherwise and our results showed that these changes may have important implications.”…

    Fengyi Guo, Jonathan Lenoir, Timothy C. Bonebrake. Land-use change interacts with climate to determine elevational species redistribution. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-03786-9

  10. Russian cuckoo invasion spells trouble for Alaskan birds: Striking difference in response to expanding brood parasites by birds in western and eastern Beringia

    Leave a Comment
    • Out of 22 experiments the researchers ran in Siberia, 14 rejected the fake cuckoo eggs. But out of the 96 experiments that we ran in Alaska, only one pair rejected one of the fake cuckoo eggs.
    • The Siberian birds are better at rejecting the cuckoo eggs perhaps because they have encountered the brood parasites before but the North American hosts have no defenses against invading cuckoos. They will be parasitized.

    May 7, 2018 University of Illinois at Urbana-Champaign  Read full ScienceDaily article here

    Common cuckoos and oriental cuckoos in eastern Russia appear to be expanding their breeding range into western Alaska, where songbirds are naive to the cuckoos’ wily ways, researchers report. A new study suggests the North American birds could suffer significant losses if cuckoos become established in Alaska.

    Like brown-headed cowbirds, cuckoos are “brood parasites,” laying their eggs in the nests of other species….. Cuckoos time their egg-laying so that their chicks will hatch first. The chicks then kick the other eggs out of the nest, “thereby eliminating the entire reproductive success of their hosts,” Hauber said….

    Vladimir Dinets, Kristaps Sokolovskis, Daniel Hanley, Mark E. Hauber. Striking difference in response to expanding brood parasites by birds in western and eastern Beringia. Journal of Field Ornithology, 2018; DOI: 10.1111/jofo.12247