Ecology, Climate Change and Related News

Conservation Science for a Healthy Planet

Category Archive: Ecology

  1. Marine noise pollution stresses and confuses fish

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    • European sea bass experienced higher stress levels when exposed to the types of piling and drilling sounds made during the construction of offshore structures.

    August 10, 2017 read full ScienceDaily article here

    The fish also showed signs of being confused when they encountered a potential predator while exposed to these underwater noises. When researchers played recordings of piling sounds and mimicked an approaching predator, the seabass made more turns and failed to move away from the predator.

    When exposed to drilling sounds the sea bass actively avoided these areas, spending more time in what the research team called the ‘safe zone’. The fish also took longer to recover from exposure to the underwater sounds.

    Over the last few decades, the sea has become a very noisy place. The effects we saw were subtle changes, which may well have the potential to disrupt the seabass’s ability to remain ‘in tune’ with its environment....

    Ilaria Spiga, Nicholas Aldred, Gary S. Caldwell. Anthropogenic noise compromises the anti-predator behaviour of the European seabass, Dicentrarchus labrax (L.). Marine Pollution Bulletin, 2017; 122 (1-2): 297 DOI: 10.1016/j.marpolbul.2017.06.067

  2. Marine reserves help solve bycatch problem in oceans

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    • Using marine reserves as a management tool could also help the recently rebounded West Coast groundfish fishery sustain itself, the study notes.

    07 Aug 2017 UC Davis see full article at ScienceDaily

    Commercial fishermen may be able to catch more of the profitable fish they want with marine reserves than without them, according to a study…


    Bycatch, where one species is unintentionally caught in pursuit of another species, is one of the most ubiquitous and crippling challenges in global fisheries. The usual solution is to dramatically reduce take of the target species to allow “weak stock” persistence. Using a general strategic model, we show that establishing areas closed to fishing can alleviate, or even completely eliminate, this problem [of bycatch]. If the weak stock is long-lived, but slow to reproduce, significantly higher yields can be obtained by using reserves than by using fishing effort controls alone. We emphasize that this is the problem plaguing the US West Coast groundfish fishery, suggesting that in that fishery, marine reserves may be a solution that simultaneously benefits fishermen and conservation.

    Alan Hastings, Steven D. Gaines, and Christopher Costello. Marine reserves solve an important bycatch problem in fisheries. PNAS August 2017. doi: 10.1073/pnas.1705169114



  3. Small streams have a big influence on our lives

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    • review of how headstreams providing habitat and refuge for diverse aquatic and riparian organisms, creating migration corridors, and governing connectivity at the watershed-scale

    07 Aug 2017 Read full ScienceDaily article here

    Small streams make up 70-80 percent of the total channel length of river networks, and they strongly influence downstream portions these networks. The role small streams — known as headstreams — … is the subject of a recent review..

    Ellen Wohl. The significance of small streams. Frontiers of Earth Science, 2017; 11 (3): 447 DOI: 10.1007/s11707-017-0647-y

  4. Gulf of the Farallones changing ocean conditions can drive prey-switching by common murres and impact fall-run Chinook salmon; co-authored by Point Blue

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    –research found that the common murres can make a difference in the number of salmon that survive to return as adults. This is especially true when ocean conditions cause the murres to feed primarily on salmon and anchovy.
    –The finding documents one of the first examples of what biologists call “bottom-up” influences—changes at the base of the food web—causing “top-down” effects on West Coast salmon, such as an increase in predation by a species higher in the chain, in this case the common murres
    salmon survival drops sharply in the years when lead the murres to prey on anchovy and salmon

    August 1, 2017 read full article here
    Interpreting relationships between species and their environments is crucial to inform ecosystem-based management (EBM), a priority for NOAA Fisheries. EBM recognizes the diverse interactions within an ecosystem—including human impacts- to consider resource tradeoffs that help protect and sustain productive ecosystems and the services they provide.
    understanding the interactions between predator seabirds, forage fish in the coastal ocean and out-migrating salmon from San Francisco Bay could improve the understanding of salmon early survival in the ocean and a measure of the possible strength of the year class return
    …In the Gulf of the Farallones, new research by scientists from NOAA Fisheries’ Southwest Fisheries Science Center, Point Blue Conservation Science, H.T. Harvey and Associates, University of California Santa Cruz, U.S. Geological Survey and the U.S. Fish and Wildlife Service found that the common murre, a small ocean seabird, can make a difference in the number of salmon that survive to return as adults. This is especially true when ocean conditions cause the murres to feed primarily on salmon and anchovy.

    Large colonies of more than 500,000 common murres nest throughout the Gulf of the Farallones, offshore of San Francisco. In typical years, with nutrient-rich water welling up from the depths, the murres prey primarily on young rockfish around their offshore breeding sites.

    When ocean conditions change, and the upwelling falters, young rockfish that are the typical prey for the murres become scarce. Then the murres switch, feeding instead on adult northern anchovies found closer to shore. That’s a problem for the young salmon entering the at these near-shore locations, because the murres eat them too..

    The finding documents one of the first examples of what biologists call “bottom-up” influences—changes at the base of the food web—causing “top-down” effects on West Coast salmon, such as an increase in predation by a species higher in the chain, in this case the common murres.

    The salmon affected are primarily fall-run Chinook, which are the primary species supporting salmon fisheries off the California Coast. …the murres preyed heavily on anchovy and salmon in 2005, which likely contributed to the collapse of the California salmon fishery in 2007 and 2008, the researchers found. Congress appropriated $170 million in disaster relief for fishermen affected by the collapse.

    New NOAA Fisheries research reveals ecosystem cascades affecting salmonCommon murres flying with forage fish (likely anchovy) in their mouths near their breeding ground on the Farallon Islands off San Francisco. Credit: Point Blue Conservation Science

    Brian K. Wells, Jarrod A. Santora, Mark J.Henderson, Pete Warzybok, Jaime Jahncke, Russell W. Bradley, David D. Huff, Isaac D. Schroeder, John C. Field and David G. Ainley. Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival. Journal of Marine Systems (2017). DOI: 10.1016/j.jmarsys.2017.05.008

    Findings include:

    • Following optimal upwelling, murre disperse more offshore to forage on rockfishes.• When rockfishes are unavailable, murre feed nearshore on northern anchovy.• Predation on out-migrating juvenile salmon is greater when murre feed nearshore.• Incidental predation on salmon inshore significantly reduces population survival.

  5. Behavioral flexibility as a mechanism for species to cope with climate change in the short term; case study on the Pika

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    • Behavioral responses, which can be rapid compared to shifts in range, may serve as early warnings of climate impacts on species.

    August 2 2017 read full ScienceDaily article here

    As climate change brings new pressures on wildlife, species must “move, adapt, acclimate, or die.” Researchers reviewed the literature on acclimation through behavioral flexibility, identifying patterns in examples from invertebrates, amphibians, reptiles, birds, mammals, and fishes, in the cover article for the August issue of the Ecological Society of America’s (ESA) journal Frontiers in Ecology and the Environment. The authors focused on the American pika (Ochotona princeps) as a case study in behavioral adaptation.

    Behavioral responses, which can be rapid compared to shifts in range, may serve as early warnings of climate impacts on species. Shifting mating seasons or migrations are common behavioral adaptations to the temperature, precipitation, humidity, wind, and other changes encompassed by climate change. Animals also adjust strategies for feeding, foraging, avoiding predators, and sheltering from inclement weather.

    Behavioral solutions, however, are limited by physiology, and sometimes incur costly trade-offs with other essential activities. An animal that spends the day in a rock crevice, sheltering from the sun, does not have enough time to forage. So changes in behavior alone are unlikely to be sufficient to adapt successfully to the predicted changes in climate over the next century….

    Erik A Beever, L Embere Hall, Johanna Varner, Anne E Loosen, Jason B Dunham, Megan K Gahl, Felisa A Smith, Joshua J Lawler. Behavioral flexibility as a mechanism for coping with climate change. Frontiers in Ecology and the Environment, 2017; DOI: 10.1002/fee.1502

  6. Research calls for enhancing long-term benefits of Farm Bill conservation incentive programs; Point Blue co-authored

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    Recommendations from improving conservation outcomes include:

    • Remove limits on re-enrollments allowed if there are a limited number of landowners interested in the program;
    • Remove limits re-enrollments where landowners must continually apply a practice for conservation outcomes;
    • Prioritize projects where landowners enroll for the long term; and
    • Consider likelihood of persistence [continuing of practices after incentives end] when designing programs.

    July 27 2017 see full PhysOrg article here 

    Many farmers, ranchers, and landowners rely on voluntary conservation incentive programs within the Farm Bill to make improvements to their land and operations that benefit them, the environment, and society. According to a recent study by researchers from Virginia Tech’s College of Natural Resources and Environment and Point Blue Conservation Science published in the scientific journal Conservation Letters, it is necessary to find ways to sustain the benefits from these practices after the incentive ends. This finding is crucial as Congress discusses the reauthorization of the Farm Bill.

    In the United States, federal incentive programs aimed at promoting private land fall under the umbrella of the Farm Bill, a package of legislation that promotes conservation efforts on farms and private lands, among other purposes. Typically taking the form of cash payments, tax credits, or cost-share agreements, these incentive programs allow to participate in conservation activities while maintaining ownership of their land.

    Persistence…is the continuation of a conservation practice after incentives from voluntary conservation programs end….

    Dayer worked with Seth Lutter, a master’s student in fish and , and Kristin Sesser, Catherine Hickey, and Thomas Gardali from Point Blue Conservation Science, a California-based and research nonprofit, to examine the existing research literature on landowner behavior after incentive programs ended to determine what factors contributed to landowners continuing conservation efforts on their own….

    In this study, supported by the S.D. Bechtel, Jr. Foundation, the authors developed five research-based explanations for whether or not persistence outcomes could be expected. The pathways include landowners’ attitudes toward the conservation practices, landowners’ motivations for participating in incentive programs, habit formation, access to resources, and social influences.

    …”More research is needed in this social science side of landowner conservation incentive programs“…. Ultimately, incentive programs that assist landowners with benefit the population as a whole.

    Private lands is critical,” Dayer said. “Often when we think about land for wildlife, we think about national parks or protected areas, but those are a small proportion. In the U.S., 60 percent of the land is privately owned.“…

    Ashley A. Dayer, Seth H Lutter, Kristin A Sesser, Catherine M. Hickey, and Thomas Gardali. Private Landowner Conservation Behavior Following Participation in Voluntary Incentive Programs: Recommendations to Facilitate Behavioral Persistence, Conservation Letters (2017). DOI: 10.1111/conl.12394
  7. Invasive plant species can enhance coastal ecosystems; better to have non-native habitat than none at all

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    • There needs to be more comprehensive and empirical assessment of invasive species’ effects before the conclusion of negative impacts is assigned.
    • Researchers hope the findings will stimulate new thinking about the effects of nonnative habitat-forming coastal plant species, which are likely to become increasingly common as human activities accelerate rates of native species losses and nonnative introductions in coastal areas.

    Posted: 17 Jul 2017 12:08 PM PDT  read full ScienceDaily article here

    Invasive plant species like seaweed can provide vital ecosystem functions in coastal areas where native habitats such as salt marshes and oyster reefs have severely declined. A new study finds that invasive species could be used to offset the loss of native habitats that provide storm protection, food production and other benefits to billions of people.

    With the progressive decline of coastal habitats worldwide, our findings suggest it’s better to have a non-native habitat than no habitat at all,“…

    On otherwise barren mudflats, habitat-forming invasive species such as nonnative seaweed can offset the loss of foundation species and provide vital ecosystem services, such as storm protection and food production, on which nearly half the human population depends.

    …”Conservation practitioners are investing millions of dollars to eradicate invasive species, but what if some of those invasive species are actually benefiting native species and ecosystem services?” said Brian Silliman, Rachel Carson Associate Professor of Marine Conservation Biology at Duke’s Nicholas School of the Environment, who co-authored the study. “Our experimental study shows for the first time that this can be the case.”

    Conservation and restoration practitioners must now begin the hard conversation about changing their black-and-white picture of invasive species impacts,” Silliman said….

    …”There needs to be more comprehensive and empirical assessment of invasive species’ effects before the conclusion of negative impacts is assigned,” said Ramus.

    Aaron P. Ramus, Brian R. Silliman, Mads S. Thomsen, Zachary T. Long. An invasive foundation species enhances multifunctionality in a coastal ecosystem. Proceedings of the National Academy of Sciences, 2017; 201700353 DOI: 10.1073/pnas.1700353114

  8. Since 1950s, 8.3 billion tons of plastics produced; 79% discarded into landfills and environment; only 9% recycled

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    • Humans have created 8.3 billion metric tons of plastics since large-scale production of the synthetic materials began in the early 1950s, and most of it now resides in landfills or the natural environment, according to a study.

    Posted: 19 Jul 2017 11:09 AM PDT  read full ScienceDaily article here

    …The researchers found that by 2015, humans had generated 8.3 billion metric tons of plastics, 6.3 billion tons of which had already become waste. Of that waste total, only 9 percent was recycled, 12 percent was incinerated and 79 percent accumulated in landfills or the natural environment.

    If current trends continue, roughly 12 billion metric tons of plastic waste will be in landfills or the natural environment by 2050. Twelve billion metric tons is about 35,000 times as heavy as the Empire State Building.

    Most plastics don’t biodegrade in any meaningful sense, so the plastic waste humans have generated could be with us for hundreds or even thousands of years,” said Jenna Jambeck, study co-author and associate professor of engineering at UGA. “Our estimates underscore the need to think critically about the materials we use and our waste management practices.“…

    They estimated that 8 million metric tons of plastic entered the oceans in 2010….

    “Roughly half of all the steel we make goes into construction, so it will have decades of use — plastic is the opposite,” said Roland Geyer, lead author of the paper and associate professor in UCSB’s Bren School of Environmental Science and Management. “Half of all plastics become waste after four or fewer years of use.”

    “I think we need to take a careful look at our expansive use of plastics and ask when the use of these materials does or does not make sense.” ….

    Roland Geyer et al. Production, use, and fate of all plastics ever made. Science Advances, July 2017 DOI: 10.1126/sciadv.1700782

  9. Birds avoid crossing roads to prevent predation

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    Why didn’t the bird cross the road? Because it was afraid of predators and venturing into another bird’s territory

    Posted: 19 Jul 2017 07:05 AM PDT  see full ScienceDaily article here

    It was once believed that roads posed no problem to birds because of their ability to fly. A new study finds that they can find these human-made structures problematic, especially small, forest-dwelling species. Their hesitance to cross roads could restrict their positive effects on the natural environment, such as seed dispersal, pollination and insect control….

    …The authors of the study strongly advise that measures are put in place to connect fragments of forest across roads, allowing wildlife to move freely…”There are wildlife-friendly solutions to many of these issues, such as specially-designed overpasses, fauna underpasses and fencing so animals can avoid accessing the road, all of which need to be incorporated into the design of our road systems. Further studies should look at the impacts of man-made breaks in vegetation, such as forest tracks and park walkways on bird movements,” adds Professor Jones. “We are currently using our data to identify the ‘at risk’ bird species within suburban areas, to assist with conservation management.”

    Christopher D. Johnson, Daryl Evans, Darryl Jones. Birds and Roads: Reduced Transit for Smaller Species over Roads within an Urban Environment. Frontiers in Ecology and Evolution, 2017; 5 DOI: 10.3389/fevo.2017.00036

  10. The Antarctic ice shelf continues to crack

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    July 19 2017  read full Grist article here

    The new rift in Larsen C emerged days after a Delaware-sized iceberg broke off from the ice shelf.

    Scientists aren’t totally sure of the implications, but it seems the ice shelf isn’t quite done breaking apart yet.

    The same team of British scientists who announced last week’s birth of the humongous iceberg spotted the crack in high-resolution satellite data. The scientists noted the crack “may result in further ice shelf loss” in a blog post published Wednesday. The huge iceberg itself has already begun to break apart.

    Ice shelves are floating extensions of glaciers, so their breakup has virtually no effect on global sea levels. The worry is the new rift is heading in the general direction of the Bawden Ice Rise, which is “a crucial point of stabilization for Larsen C Ice Shelf,” according to the British team. A destabilized Larsen C could speed up the flow of its parent glaciers to the ocean, which would have a slight effect on sea levels.