ESA Selects 2019 Katherine S. McCarter Graduate Student Policy Award Recipients

Read more about each award winner and view photos on ESA’s Ecotone blog

 

February 13, 2019
For Immediate Release

Contact: Alison Mize, alison@esa.org, (202) 833-8773 ext. 205

 

The Ecological Society of America (ESA) is honored to announce this year’s Katherine S. McCarter Graduate Student Policy Award (GSPA) recipients. This award provides graduate students with the opportunity to receive policy and communication training in Washington, D.C. before they meet lawmakers.

Ten students were selected for this year’s award: Kristina J. Bartowitz (University of Idaho), Vanessa Constant (Oregon State University), Hannah E. Correia (Auburn University), Brett Fredericksen (Ohio University), Sara Gonzalez (University of California, Santa Cruz), Emily Kiehnau (University of Oklahoma), Charlotte R. Levy (Cornell University), Timothy J. Ohlert (University of New Mexico), Christopher Kai Tokita (Princeton University) and Emory H. Wellman (East Carolina University).

Students will travel to D.C. in March to learn about the legislative process and federal science funding, to hear from ecologists working in federal agencies, and to meet with their Members of Congress on Capitol Hill. This Congressional Visit Day, organized and sponsored by ESA, offers GSPA recipients the chance to interact with policymakers and discuss the importance of federal funding for science, in particular the biological and ecological sciences.

“Scientists who are confident in their ability to communicate with decision-makers are needed more than ever to bridge the gap between science and policy,” said ESA President Laura Huenneke. “The Katherine S. McCarter Graduate Student Policy Award provides real-life, hands-on experience for early career ecologists. The Society is grateful to be able to assist a number of individuals each year in advancing their effectiveness in this crucial arena.”

Click here to see a Flickr album with photos of this year’s award winners.

Read more here about the award winners on ESA’s Ecotone blog.

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

Pika survival rates dry up with low moisture

In the Pacific Northwest, dry air interacts with low snow conditions to affect pika abundances at different elevations

 

February 4, 2019
For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

An American pika pokes its head above the grass in New Mexico. Photo courtesy of Thomas Barlow.

Although it has been ranked as the cutest creature in US National Parks, the American pika is tough, at home in loose alpine rocks in windswept mountain regions. Related to rabbits and hares, pikas live in cold, wet climates and high terrain, spending winters in snowy homes living off of stored grasses and other forage they have gathered, only venturing out for more when weather permits.

Unfortunately for these adorable little mammals, they have a fairly severe sensitivity to overheating – they die if they are exposed to temperatures above 77°F for longer than six hours. Due to their lethal threshold for heat stress, pikas are indicators of how changing environmental conditions can affect mountain-dwelling species.

It might appear that the danger for pikas lies mostly with increasing temperatures and summer heat extremes. In some cases, however, decreased snowpack and lower air moisture may threaten pikas more.

Vapor-pressure deficit (VPD) can be likened to air’s aridity – higher VPD is drier. VPD governs the growth of many plants that pikas depend on for food, and controls cloud formation and snow. If VPD becomes higher, it will inhibit the growth of plants that pikas depend on for food, and will shrink snow packs which they use for insulation against extreme temperature. The snowpack also stores water until springtime, when it provides water for forage plants that pikas eat.

A team of researchers lead by Aaron N. Johnston of the U.S. Geological Survey sought to understand how climate change, specifically changes in snowpack and VPD, is affecting pikas. In a paper published recently in the Ecological Society of America’s journal Ecology, they related population abundances to weather and snowpack dynamics in the North Cascades National Park Service Complex in Washington state. In the Pacific Northwest, a place with mild summers and prevailing cool, moist conditions, pikas occur at unusually low elevations including near sea level.

A pika carries a mouthful of forage in decent weather, possibly to store it away in its home. Photo courtesy of Thomas Barlow.

The study period included a year with record-low snowpack and high VPD (very dry air) in winter of 2014-2015, a data point that provided valuable observations of these variables’ influences on the ecosystem. The researchers further studied the dynamics across differing elevations – low, middle, and high.

The results were surprisingly variable, with different dynamics acting over different elevations.

“We expected snowpack to be an important factor because it has many important ecological functions for pikas,” said Johnston. “The effect of VPD in winter was a big surprise.”

At the lowest elevations, populations declined markedly. Unusually high VPD during the snow drought dried up forage plant species accustomed to moist conditions, and lack of food may have prompted malnourished pikas to forgo reproduction. Cold exposure did not appear to affect these pikas, where absence of snowpack is common because of generally warm temperatures.

At middle elevations, it was cold stress, not dry air, that had the biggest effect. Along a narrow elevation band, about 1200-1500 meters, pika populations lacked a strong snowpack in which to seek shelter and insulation from extreme cold. However, it was a dip in reproduction the following year, not pika mortality in a single winter, that caused the population abundance to drop. Pikas may have even resorbed fetuses in response to the cold stress of the snow drought.

With their sensitivity to overheating, pikas are an indicator species for how climate change may affect mountain-dwelling wildlife. Photo courtesy of Shana Weber.

At high elevations, where snow often persists for up to 7-9 months, forage came back into play as the important driver of abundances. Populations increased, having had sufficient snow cover for insulation despite a snow drought, and having benefitting from increased forage availability due to earlier snowmelt and a longer growth season for food. Pikas were able to consume and collect enough food to increase their health and ability to produce many offspring over the following winter.

Given the pervasive influence of moisture on the physiology of plants and animals, the authors find the lack of previous studies on animal responses to VPD surprising.

“Moisture is distinct from climatic factors of temperature and precipitation that are commonly used to explain animal distributions,” Johnston stated. “Incorporating moisture into species distribution models should improve ecological understanding of species and their responses to climate change.”

Climate-indicator species like pikas provide a number of ecosystem services and play an important role in biodiversity. Pikas serve as a food source for a number of predators, including weasels, coyotes, and birds of prey. They are also ecosystem engineers – their foraging helps promote the diversity and distribution of various plant species and nutrients. Consequently, pika die-offs could have many lasting dire consequences for the environment and serve as a harbinger in forecasting potential climate change impacts on animal and plant life across the greater continental US.

As extreme events like snow drought continue to increase in frequency, how these events and their interactions with VPD will affect animal species remains largely unexplored. Support for continued research into climate indicator species such as the pika is critically important.

Photo courtesy of Thomas Barlow.

 


Journal Article

Johnston, Aaron N., et al. 2019. “Ecological consequences of anomalies in atmospheric moisture and snowpack.” Ecology. DOI: 10.1002/ecy.2638

 

Authors

Aaron N. Johnston, USGS Northern Rocky Mountain Science Center; University of Washington School of Envrionmental and Forest Sciences

Jason E. Bruggeman, Beartooth Wildlife Research

Aidan Beers, University of Colorado Boulder Department of Ecology and Evolutionary Biology

Erik A Beever, USGS Northern Rocky Mountain Science Center; Montana State University

Roger Christophersen and Jason I. Ransom, National Park Service, North Cascades National Park Complex.

 

Author Contact:

Aaron N. Johnston         ajohnston@usgs.gov

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

 

Why charismatic, introduced species are so difficult to manage

Researchers say mismatches of scale between social and ecological systems are a key contributor to many conflicts involving introduced-species management

 

February 4, 2019
For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

Introduced and invasive species can present big problems, particularly when those species are charismatic, finds a recently published paper in the Ecological Society of America’s journal Frontiers in Ecology and the Environment.

People tend to have a more favorable view of species that are large; do not bite, crawl, or squirm; are not oily or slimy; or are culturally valued. Some introduced species, like zebra mussels, tend to be reviled by the public, and people willingly adhere to strict management policies.

However, if an animal has that elusive quality of charisma, people often don’t want it to be controlled, even if it’s harming the environment. Inevitably, these imbalances in public perception of introduced species influence the way those organisms are managed.

Ring-necked parakeets and feral domestic pigeons both frequent some urban areas in the UK, and people have grown used to seeing them in their local parks. Photo courtesy of Loz Pycock.

Take the ring-necked parakeet (Psittacula krameri) for example. The pet trade has led to an established population of parakeets in Europe, far outside the species’ native range. Even though parakeets can transmit diseases to native birds, compete with them for nesting cavities, and are recognized as a crop pest, the public enjoys seeing them in parks, gardens, and homes. Introduced parakeets tend to be released in cities, but the parakeets actually exact the most damage in rural areas. But because people have grown used to them, they are likely to oppose eradication efforts that take place before the birds become an established nuisance.

Opposition to the management of charismatic species can be exacerbated by these “social–ecological mismatches” – differences between the scales of interacting social and ecological systems. In the parakeets’ case, the introduced birds have not been around for more than a few decades, which is not a long time on an ecological scale. But it is long for humans – many have grown up knowing the parakeets are part of their neighborhood, and so oppose efforts to manage them.

A group of researchers from the US Geological Survey (USGS) and universities in the US and UK explored how public perception and management actions toward charismatic, introduced species are often at odds with the ecological characteristics of these populations.

The paper argues that scale – and specifically for mismatches of scale between social and ecological systems – is a key influence on many conflicts involving introduced-species management. In a nutshell, the average citizen or policymaker experiences things in “human time” while ecosystems and introduced species experience things in “ecosystem time.” The same goes for differences in spatial scale; humans experience things on a human scale – their neighborhood, their city, things at the level of their own experience – while ecosystems and invasive species have more far-reaching consequences that are tough for people to comprehend. This makes it difficult to enact policies that are in line with the way ecosystems behave and species invasions occur.

The researchers explore other cases of introduced species and suggest ways to establish science-based strategies for managing them while also maintaining public trust.

Horses have been integral to human life throughout history, and hold widespread cultural significance. But horses are not native (at least in the modern era) to many of the places where they currently roam. Photo courtesy of Steve Petersen.

Free-roaming horses (Equus caballus) are another example. Horses have been integral to human life throughout history, and hold widespread cultural significance. But horses are not native (at least in the modern era) to many of the places where they currently roam, and many of their populations have high growth rates. Some nations, like Australia, cull their wild horse populations in an attempt to control grazing impacts on indigenous plants. In an Argentinian provincial park, wild horses have reduced native plant cover and allowed invasive pines to gain a foothold – a result that conflicts with the park’s fundamental management goal of preserving the native grasslands.

In the US, there are nearly three times as many horses on rangelands than the Bureau of Land Management (BLM) has said is appropriate. One of the more socially acceptable management practices is to relocate them to holding facilities, but these can be overcrowded and take up a considerable portion of BLM funding.

Lead author Erik A. Beever of USGS explains that, as with the parakeets, social and ecological scales are at odds with each other for these iconic mammals. Management approaches can be standardized at the state or national level, yet the differences in how horses’ influences play out in nature illustrate the importance of locally-relevant approaches. “Horses can move very far,” he said, “but their management areas can be small and the boundaries do not shift over time or account for seasonal movement.” Additionally, management decisions and projects may take months to years to come into effect, while natural events can shift horse populations in days or weeks.

These differences in the scales at which social and ecological systems interact with introduced species create multi-faceted management and conservation challenges. However, Beever and his colleagues hope that shedding some light on this fundamental problem will aid management tactics in the future.

“There are tools, techniques, and approaches that can help to bring progress and even resolution to these situations,” he says. “Addressing social–ecological mismatches will be an important element to effectively manage introduced species; this will require early, meaningful communication about complex management issues among researchers, managers, and the public, and a collaborative search for practical solutions and compromises.”

 


Journal

Beever, Erik A., et al., 2019. “Social–ecological mismatches create conservation challenges in introduced species management.” Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2000

 

Authors

Erik A. Beever and Robert Al-Chokhachy, US Geological Survey, Northern Rocky Mountain Science Center; Department of Ecology, Montana State University

Daniel Simberloff, Department of Ecology and Evolutionary Biology, University of Tennessee

Sarah L. Crowley, Environment and Sustainability Institute, University of Exeter

Hazel A. Jackson, Durrell Institute of Conservation and Ecology, School of Anthropology and Conservation, University of Kent

Steven L. Petersen, Plant and Wildlife Sciences Department, Brigham Young University

 

Author Contact:

Erik A Beever     ebeever@usgs.gov

 

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The Ecological Society of America, founded in 1915, is the worlds largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in ecological science. Visit the ESA website at http://www.esa.org

 

ESA Tipsheet for January 31, 2019

Upcoming research in Frontiers in Ecology and the Environment

 

Wednesday, 30 Jan 2019
For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

Get a sneak peek into these new scientific papers, publishing on January 31, 2019 in the Ecological Society of America’s journal Frontiers in Ecology and the Environment.

  • Parks for sharks are most successful when humans aren’t around
  • Fisheries management efforts are responsible for recovering fish populations in the Northeast Atlantic
  • Building best management practices for drinking water and air quality
  • Coral reefs can benefit from probiotics, too
  • Why it’s harder to manage parakeets than zebra mussels

 

Banning fishing isn’t enough for sharks on the Great Barrier Reef

Photo courtesy of Ashley Frisch.

On the Great Barrier Reef of Australia, sharks often receive priority status in conservation programs, but their populations have still declined across much of the region. Over the past forty years, a number of marine reserves (“parks”) have been established to protect sharks from being fished, and a few restrict human entry entirely. Researchers from the Great Barrier Reef Marine Park Authority and from the University of Tasmania compared different types of reserves encompassing a range of ages to determine the conditions that are most conducive to shark population recovery. Even though it is illegal to kill sharks in all of the reserves they studied, the researchers found that shark populations improved significantly more when all human entry was prohibited, suggesting that illegal extractive activities in the less stringent “no-take” reserves, where it is easier to get away with fishing, may be responsible for the projected disparity in shark recovery.

Author Contact: Ashley Frisch (ashley.frisch@gbrmpa.gov.au)

  • Frisch A and Rizzari JR. Parks for sharks: human exclusion areas outperform no-take marine reserves. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2003

 

Regulation – not natural change – is responsible for improving Northeast Atlantic fish populations 

Photo courtesy of Fabian Zimmerman.

Overfishing isn’t the only thing that is harmful to fish, so when dwindling fish populations do recover, it can be difficult to determine whether the improvements are due to tougher regulations on fishing, or if the populations simply bounced back because of environmental changes and natural fluctuations. A study of fishing areas across the Northeast Atlantic examined fishing reports, along with biomass and survival data, back to 1960 to determine whether the recent recovery of fish stocks in this area can actually be attributed to stricter regulations. The researchers found that reductions in fishing effort after the year 2000 were more strongly correlated with fish population recovery than natural changes in recruitment, and suggest that climate change-induced shifts in species distributions will amplify the need for science-based marine management strategies.       

Author Contact: Fabian Zimmermann (Fabian.zimmermann@hi.no)

  • Zimmermann F and Werner KM. 2019. Improved management is the main driver behind recovery of Northeast Atlantic fish stocks. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2002

 

Using people’s locations and preferences to help prioritize ecosystem services

Photo courtesy of Bonnie Keeler.

Because resource managers have limited funds, they sometimes have to make tough decisions when it comes to conservation. In agricultural landscapes, best management practices, or “BMPs,” are used to conserve ecosystem services like drinking water, clean air, recreation, and crop production. But there are trade-offs associated with BMPs: one BMP that would benefit groundwater quality might be implemented at the expense of another that would otherwise boost crop yields. What’s more, decisions to select one BMP over another are often made without regard to the location and well-being of the people who rely on the services in question. Researchers from the University of Minnesota, the University of Vermont, and the Nature Conservancy compared how different BMPs would affect supplies of ecosystem services in a sub-basin of a watershed in eastern Iowa, by visualizing where those supplies were located in relation to the human users who most value them.

Author contact: Bonnie Keeler (keeler@umn.edu)

  • Keeler BL, Dalzell BJ, Gourevitch J, et al. 2019. Putting people on the map improves the prioritization of ecosystem services. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2004

 

A healthier “microbiome” might buy corals some time  

Photo courtesy of Hannah Epstein.

The “gut microbiome” concept that is becoming increasingly popular in discussions of human health (e.g. fecal microbiota transplants or probiotic supplements) can also be applied for organisms that don’t have a “gut” at all: corals. When corals experience stress, they expel the nutrient-supplying microbes that give coral reefs their colorful palette – leading to mass “bleaching” of entire reefs. Inoculating corals with specially engineered microorganisms (e.g. those that are heat-resistant) may make it easier for coral reefs to adapt to changing ocean conditions. After reviewing the current body of literature on microbiome engineering in corals, a team of researchers from James Cook University and the Australian Institute of Marine Science identified the main research priorities that will be needed to push the field of study past the “proof of concept” stage. They suggest that while corals will be unlikely to thrive without substantial intervention in deteriorating ocean conditions, microbiome engineering may be a strategy that can at least buy corals some time.  

Author Contact: Hannah Epstein (hannah.epstein@my.jcu.edu.au)

  • Epstein HE, Smith H, Torda G, and van Oppen MJH. Microbiome engineering: enhancing climate resilience in corals. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2001

 

Why charismatic introduced species are so difficult to manage

Photo courtesy of Erik Beever.

People tend to have a more favorable view of species that are large, do not crawl or squirm, are not oily or slimy, and are culturally valued. Some introduced species, like zebra mussels, tend to be reviled by the public, but others are more charismatic, and these imbalances in public perception of introduced species influence the way those species are managed. For example, the pet trade has led to an established population of parakeets in Europe far outside the species’ native range. Even though the parakeets can transmit diseases to native birds and are recognized as a crop pest, the public enjoys seeing them in local parks and gardens and is likely to oppose eradication efforts. A group of researchers from the US Geological Survey and several universities in the US and UK explored how public perception and management actions towards such charismatic introduced species are often at odds with the actual ecological characteristics of the introduced populations: Introduced parakeets tend to be released in cities, and have been around just long enough for the public to become accustomed to them, but the parakeets actually exact the most damage in rural areas, and because they have not yet become an ecological fixture in the surrounding landscape, they can in fact still be managed before they become a true nuisance. The researchers explore similar cases of introduced salmonid and free-roaming horses, and suggest ways to establish science-based strategies for managing introduced species while also maintaining public trust.     

Author Contact: Erik Beever (ebeever@usgs.gov)

  • Beever EA, Simberloff D, Crowley SL, et al. Social–ecological mismatches create conservation challenges in introduced species management. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.2000

 

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The Ecological Society of America, founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in ecological science. Visit the ESA website at http://www.esa.org

An Icy Forecast for Ringed Seal Populations

New mathematical model shows dramatic decreases in ringed seal populations due to projected low snow conditions

 

January 23, 2019
For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

Arctic sea ice is now declining at a rate of 12.8 percent per decade – 2012 had the lowest amount of summer ice on record. The drastic change has numerous implications for Arctic ecosystems, from increased shipping – the first commercial container ship crossed the Arctic Ocean in fall 2018 – to changing food webs.

But for ringed seals across the Arctic, it’s not the lack of ice that will hurt them most – it’s the lack of snow.

A ringed seal pup, still covered in its white baby fur, lies exposed on the sea ice. Photo courtesy of Ian Stirling.

While ringed seals (Phoca hispida) rely on stable sea ice in order to birth pups and raise them, they also rely on sufficiently deep snow drifts in which to dig lairs, which are much like snow caves and can mean the difference between life and death. The lairs provide insulation from extreme cold and offer some protection from predators, keeping their young ones out of view from wandering polar bears – their main predator – until they are weaned. Killer whales, walruses, wolves, dogs, wolverines, sharks, and even gulls prey on pups. Along with providing shelter, there are breathing holes within the lair that allow direct access to the waters below for the seals to hunt polar and Arctic cod and a variety of planktonic crustaceans necessary for survival. During years with poor snow cover, pups can be born on the surface of the ice, but mortality of these pups that weigh only ten pounds at birth is extremely high.

Scientists have already observed and predicted that high pup mortality rates are linked to poor environmental conditions like early ice breakup and low snow. Researchers have now gone a step further by coupling these hypotheses with forecasts of future spring snow and ice conditions, developing a mathematical model, and following it to some stark conclusions for populations off the Amundsen Gulf and Prince Albert Sound in Canada.

The paper appears today in the Ecological Society of America’s journal Ecological Applications.

A ringed seal lies on the ice, ready to make a quick escape into the water. Note the ringed pattern on it’s coat, from which the species’ name is derived. Photo courtesy of Rinie Van Meurs.

“It was surprising to see just how little snow is forecast to be available for the construction of lairs in the future,” said lead author Jody Reimer, PhD candidate at the University of Alberta. She was surprised both by the magnitude of the projected population declines – ranging from 50 to 99 percent by the year 2100 – as well as by the fact that these declines appear to be largely driven by insufficient snow on the ice, rather than early ice breakup.

In addition to overall seal population declines, the model projects that there will be a smaller proportion of juveniles relative to adults and pups over time, as fewer pups make it to their teenage years. In general, each successive generation gets a little bit smaller, and the effects of this are seen most acutely in the juvenile stages, especially for a long-lived ringed seals with lifespans up to 43 years.

Reimer also says these results and predictions would not have been made without the new mathematical model, which revealed glaring issues with previous observations, namely adult annual survival.

“When we put the previously published demographic estimates into our model, it predicted dramatic population declines that are inconsistent with the fact that ringed seals still exist in that area,” Reimer said. Ringed seals are considered a somewhat cryptic species, being notoriously difficult to study. Estimates of survival and reproductive rates have been collected over the years, but these estimates had not been combined into a population-level model until now.

Ringed seal geographic range across the Arctic. Photo courtesy of NOAA Alaska Fisheries Science Center.

Ringed seals’ dependence on sea ice and snow makes them good indicators of

change. They are the most abundant Arctic seal, with a huge geographic distribution, and are thus exposed to a wide range of climate change impacts. Additionally, changes in the community composition of Arctic marine systems can be seen through their diet as they shift their prey in response to what is available.

So, as an indicator species, ringed seals provide information on the health of Arctic marine ecosystems. But this information relies on the ability to detect the large scale changes resulting from climatic changes. Furthermore, future ecological challenges must be anticipated. For ringed seals in particular, given their sensitivity to snow cover, a better understanding – and modelling – of factors affecting adult survival is essential for assessing population viability as the Arctic climate changes.

It appears that Reimer and her colleagues are well on their way to anticipating these changes – “I think this is an example of an instance in which modelling can really help with the interpretation of field data and help inform future field endeavors.”



Journal Article

Reimer, Jody, et al. 2019. “Ringed seal demography in a changing climate.” Ecological Applications. DOI: 10.1002/eap.1855

 

Authors

Jody Reimer, Mark Lewis: University of Alberta, Biological Sciences, Mathematical and Statistical Sciences

Hal Caswell, University of Amsterdam Institute for Biodiversity and Ecosystem Dynamics; Woods Hole Oceanographic Institution

Andrew Derocher, University of Alberta, Biological Sciences

 

Author Contact:

Jody Reimer   jrreimer@ualberta.ca

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

 

ESA Endorses Four-Dimensional Ecology Education Framework

January 14, 2018
For Immediate Release

Contacts: Teresa Mourad, 202-833-8775, teresa@esa.org
                 Alison Mize, 202-833-8773, alison@esa.org

 

The Ecological Society of America announces a Society-endorsed undergraduate education framework, termed the Four-Dimensional Ecology Education (4DEE) framework.

The 4DEE framework positions ESA as a leader in educational programming and/or professional development, provides opportunities to expand membership and partnerships, and can serve as a foundation for the development of K-12 educational standards. Practitioners of ecology – such as consultants and others seeking certification – can use the framework to guide their professional preparation in the discipline.

“This framework incorporates three decades of discussion regarding the key ideas in modern ecological science that can be included in undergraduate curriculum, as well as a recognition of recent pedagogical advancements,” said Pamela Templer of Boston University and ESA Vice President of Education and Human Resources.

The framework has several prospective audiences and potential applications. At the foreground are faculty, curriculum designers, administrators, education researchers, and students. The framework would be particularly useful to instructors whose undergraduate or graduate training did not include a heavy emphasis in ecology. It is intended to encourage the idea that ecology should be taught and learned through multiple dimensions.

“As a former dean and provost, I know that colleges and universities are under pressure to describe what their students know and can do with their education,” explained Laura Huenneke, ESA President. “This framework will help faculty make a case for ecology programs and help administrators make resource allocation decisions to support those programs.”

Wilkes University students learning how to key out vascular plant species in a bog, and sampling vegetation plots associated with a natural gas pipeline, in northeastern Pennsylvania. Photos courtesy of Kenneth Klemow.

Collectively containing 21 topics or “elements”, the four dimensions include: Core Ecological Concepts (the hierarchy of individuals to the biosphere), Ecology Practices (skills that ecologically literate people should have), Human-Environment interactions, and Cross-Cutting Themes like scale, evolution, and disturbance.

“The 4DEE process has only just started,” stated George Middendorf of Howard University and chair of the 4DEE Task Force. “Our next step is to create an implementation plan to ensure ongoing support and periodic review of the 4DEE framework”.

The endorsement of the 4DEE framework by the ESA’s Governing Board represents a significant forward leap in defining ecological literacy. ESA hopes that it gains widespread use and realizes its full potential.

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

Elephants take to the road for reliable resources

In a national park, researchers study African elephant movement and vegetation using satellites


January 9, 2018

For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

An elephant never forgets. This seems to be the case, at least, for elephants roaming about Namibia, looking for food, fresh water, and other resources.

The relationship between resource availability and wildlife movement patterns is essential to understanding species behavior and ecology. Landscapes can change from day-to-day and year-to-year, and many animals will move about according to resource availability. But do they remember past resource conditions? Just how important is memory and spatial cognition when seeking to understand wildlife movement?

Researchers in Etosha National Park, Namibia, examined this question through an iconic mammal. “African elephants (Loxodonta africana) are ideal for this study – they have excellent cognitive abilities and long-term spatial memory,” lead author Miriam Tsalyuk of University of California Berkeley explained, “which helps them return to areas with better food and water. African savannas are unpredictable with a prolonged dry season, where knowledge of the long-term availability of resources is highly advantageous.” The study was published today in the Ecological Society of America’s journal Ecological Monographs.

A group of African elephants moves across the Etosha National Park in Namibia, Africa. Photo courtesy of Miriam Tsalyuk.

Using GPS collars, the researchers tracked the movement of 15 elephant groups for periods ranging from 2 months up to a little over 4 and a half years. Key to this study, Tsalyuk emphasized, were satellite-based imagery and observations, which were used to create detailed data on vegetation types and biomass. Together with maps of surface water and man-made constructs, Tsalyuk and her colleagues then correlated these variables with the elephant movement data to look for patterns in behavior.

“Most ecological research to date examines how wildlife respond to the current environmental state,” she said. “However, animals use spatial and social memory to return to locations that have been beneficial in the past. Satellite imagery provides information about these past conditions and unravels the complexity of wildlife spatial use.”

Their analyses revealed that the elephants certainly seem to remember where to find the best food and reliable water. Long-term information (up to a decade) on forage conditions was a bigger factor in elephants’ decisions where to go than current conditions, particularly in the dry season.

“The results were very surprising indeed,” Tsalyuk said. “We thought that if we could capture the vegetation conditions as close as possible to the time the elephants passed there, we could better explain preference for a particular location. But we found the complete opposite – elephants have a stronger preference for locations where forage conditions have been better for many years, over the forage availability they see around them at the moment.”

The researchers were also surprised about the variability of the elephants’ preference for resources – different vegetation types and water sources – over time of day and over seasons.

Elephants’ strong inclination to be close to water is expected in the semiarid environment of Etosha. Preference for permanent water sources increases as rainfall declines. As the dry season progresses, elephants become increasingly dependent on artificial (human-made) water sources, such as bore holes. 

Collared African elephants like this one near a water source helped supply movement data for the study. Photo courtesy of Miriam Tsalyuk.

Somewhat less expected was the elephants’ fondness to walk close to roads.

“Roads are often dangerous to wildlife,” Tsalyuk said. “However, this research was performed within Etosha National Park, where most of the roads are dirt roads with relatively little traffic.” Elephants highly preferred to travel along roads in the dry season, when road conditions are best and when the elephants need to move farther between water and vegetation resources. It seems they use roads as easy walking terrain to conserve energy.

It’s possible that they may also take advantage of browsable plants in roadside ditches, or could position themselves behind tourist vehicles as a potential shield from predators.

The elephants in Etosha prefer areas with higher grass biomass, but lower tree biomass. When food is abundant, the elephants feel more comfortable to explore the landscape for greener patches or higher quality forage. In the dry season, however, when food becomes scarcer and less nutritious the goal becomes reducing the risk of starvation, and the elephants restrict themselves to areas where forage productivity has been favorable for many years.

Elephants are important ecosystem engineers – they control habitat conditions or availability of resources to other organisms. For example, they enhance plant diversity by suppressing tree cover and promote seed dispersal and nutrient transport, while dense elephant populations may cause vegetation degradation and tree damage. Unfortunately for these integral animals, elephant populations throughout Africa are in steep decline in the last decade due to poaching and greater restriction of their range.

If we want to better understand the changes in elephant–savanna vegetation dynamics and to improve land management, it is crucial to account for the variation in the movement-related responses of elephants to changing resources.

 


Journal Article

Miriam Tsalyuk, et al., 2018. “Temporal variation in resource selection of African Elephants follows long term variability 2 in resource availability.” Ecological Monographs. DOI: 10.1002/ecm.1348.

 

Authors

Miriam Tsalyuk, Department of Environmental Sciences, Policy & Management, University of California Berkeley

Werner Kilian , Etosha Ecological Institute, Namibia

Björn Reineking, Université Grenoble Alpes, France

Wayne Marcus Getz, School of Mathematical Sciences, University of KwaZulu-Natal, South Africa

 

Author Contact

Miriam Tsalyuk      miri.tsa@gmail.com

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

Does mountaintop removal also remove rattlesnakes?

Mining operations in Appalachia permanently alter habitat availability for rattlesnakes

 

January 3, 2018
For Immediate Release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

Timber rattlesnakes, according to the study’s author, are among the most docile creatures in Appalachia. Photo courtesy of Thomas Maigret.

On the Cumberland Plateau in eastern Kentucky, surface coal mining is destroying ridgelines and mountaintops, and along with them, the habitat of a surprisingly gentle reptile species – the timber rattlesnake.

“Timber rattlesnakes may be the most docile, calm animals of their size in eastern US forests,” Thomas Maigret, a researcher from the University of Kentucky, said. “On several occasions, I’ve witnessed spiders using a rattlesnake as an anchor for a web. Females, especially, move very infrequently, and pose almost no threat to a careful human.”

Unfortunately for the timber rattlesnake (Crotalus horridus) and other species in this region – both plant and animal – surface coal mining requires complete removal of mature forest cover and the upper soil layers. This means that soil is scraped away, rocks disturbed and dug out, plants and trees removed, or the ridgetop landscape flattened and made more uniform to reach the coal buried in the earth. This alteration eliminates many diverse, unique places for animals to live and hibernate. The central Appalachia region spans eastern Kentucky, northeastern Tennessee, southwest Virginia, and southern West Virginia and is one of the most diverse non-tropical ecosystems in the world with thousands of plant and animal species, many that are only found there.

Maigret and his colleagues tracked timber rattlesnakes in a study published today in the Ecological Society of America’s journal Frontiers in Ecology and the Environment. The researchers implanted radio transmitters in snakes of the Cumberland Plateau and tracked their movements until they retreated to hibernation sites in the fall. The data gathered provided a roadmap for identifying other potential hibernating sites, or “hibernacula,” across the study area.

“Snakes of the eastern U.S. vary in their hibernacula selection behavior, and for many species not much is known about hibernacula preferences,” Maigret explained. “For example, many aquatic snakes prefer damp hibernacula near the streams where they reside during the summer. But for other species, any warm, protected crevice they can fit into seems to suffice.”

By analyzing remote-sensing and satellite imagery, mining maps, and permit data from the USGS and other sources, the researchers were then able to determine how mining might affect a wide range of hibernation sites.

Timber rattlesnakes choose places to hibernate that are more likely to be surface mined due to their ridgetop locations. Mining thus puts this species at a disadvantage and reduces the biodiversity of the area. Photo courtesy of Thomas Maigret.

They found that because timber rattlesnakes tend to hibernate in the same places that make ideal mines, surface mining disproportionately alters or eliminates their preferred habitat. “Other species with habitat preferences similar to timber rattlesnakes – including some snakes – may also be affected disproportionately by mining. On the other hand,” Maigret said, “species associated with middle or lower slopes will not be affected by mining to the same extent.”

In other words, the mining operations here are selecting against timber rattlesnake habitat, effectively cutting into the region’s biodiversity.

The Surface Mining Control and Reclamation Act of 1977 does not require mining companies to reforest the area to the original mountaintop landscape after mining has wrapped up. The law does dictate that the “approximate original contours” of a site be re-established, in an attempt to not leave the area uninhabitable by the species that once lived there. However, it is rare for forests and biodiversity to fully recover from mining-related disturbances, to the detriment of many animals and their habitats.

Is the damage done to mountain-tops irreversible? While researchers are actively improving the ability to restore habitats on reclaimed mine lands, surface mining acts as an eraser of unique ecosystems, creating a uniform landscape where there once were diverse habitat options. In the Cumberland Plateau, mining leaves conservation and management efforts very little to work with even after an operation restores the approximate original mountaintop landscape.

Still, Maigret is optimistic about the future of restoring mined areas for the docile rattlesnakes. “Coal mining in central Appalachia has serious economic headwinds,” he stated, “and may never return to the rates of surface mining of the late 20th century. Timber rattlesnakes are resilient, and their ability to adapt to previous landscape changes – including massive deforestation in the 19th and early 20th century – should not be underestimated.”

 


 

Journal Article

Maigret T.A., Cox J.J., and Yang J. 2019. Persistent geophysical effects of mining threaten ridgetop biota of Appalachian forests. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.1992

 

Authors

Thomas A. Maigret, Department of Biology, Department of Forestry and Natural Resources, University of Kentucky          

John J. Cox and Jian Yang, Department of Forestry and Natural Resources, University of Kentucky  

 

Author Contact

Thomas A Maigret (thomas.maigret@uky.edu)

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

ESA Tipsheet for January 2019

Upcoming research in Frontiers in Ecology and the Environment

 

December 28, 2018
For immediate release

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org

 

Get a sneak peek into these new scientific papers, publishing on January 3, 2019 in the Ecological Society of America’s journal Frontiers in Ecology and the Environment.

  • Flashing lights can protect alpaca and llama herds from pumas
  • Does mountaintop removal in Appalachia also remove rattlesnakes?
  • How quickly can ponds “inhale” and store carbon?
  • Machine-learning shows what’s changed in ecological research over forty years

 

Flashing lights can scare off some predators from llamas and alpacas

A puma is caught on camera at night during a study to see if flashing lights are a viable non-lethal predator deterrent for protecting llama and alpaca herds. Photo courtesy of Omar Ohrens.

Historically, lethal methods for protecting livestock from predators have contributed to the decline of terrestrial carnivore populations in many ecological communities. While non-lethal alternatives abound (and many local indigenous farmers prefer them), most of these methods have not been rigorously tested to determine whether they are effective. A team of researchers from the University of Wisconsin and from Chile’s Pontifícia Universidad Católica deployed an array of flashing light deterrents across their study area on the Altiplano, or Andean Plateau, which stretches across a portion of Chile and Bolivia, where pumas and Andean foxes prey on llama and alpaca herds. The researchers found that the light devices effectively deterred predation on their herds by pumas, but not by Andean foxes. This study represents a step forward in establishing experimental protocols for assessing the effectiveness of strategies and products that help humans and wildlife coexist.

Author Contact: Omar Ohrens (ohrens@wisc.edu)

  • Ohrens O, Bonacie C, and Treves A. Non-lethal defense of livestock against predators: flashing lights deter puma attacks in Chile. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.1952

 

Coal miners and rattlesnakes prefer the same type of topography

Timber rattlesnakes are disproportionately affected by landscape and habitat disturbances by coal mining. Photo courtesy of J Hutton.

On the Cumberland Plateau in eastern Kentucky, surface coal mining remains a common method of coal extraction and requires complete removal of mature forest cover and the upper soil layers. Even though federal law requires mining companies to approximately reconstruct the original topography after mining has wrapped up, it is rare for natural succession, native forest growth, and terrestrial biodiversity to return to their original levels. To determine how surface mining affects ridgetop habitat availability, researchers from the University of Kentucky implanted radio transmitters in timber rattlesnakes (Crotalus horridus) and tracked their movements until the snakes retreated to hibernation sites in autumn, which provided a roadmap for identifying other potentially viable hibernating sites, or “hibernacula,” across the study area. By analyzing a suite of LiDAR remote-sensing and satellite imagery, mining maps, and permit data from the USGS and other sources, the researchers were then able to determine how mining might affect the range of rattlesnake hibernacula. They found that because timber rattlesnakes tend to overwinter in the same places that make ideal mines (along ridgelines and other similar higher-elevation topographic features), surface mining disproportionately alters or eliminates the preferred habitat of this species. These ridgetops contain other plant and animal species that may be similarly affected. The authors’ analyses also show that restoring mined areas in Appalachia will be difficult, especially where ridgetop topography has been permanently rearranged.   

Author Contact: Thomas A Maigret (thomas.maigret@uky.edu)

  • Maigret TA, Cox JJ, and Yang J. 2019. Persistent geophysical effects of mining threaten ridgetop biota of Appalachian forests. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.1992

 

Stashing carbon in small ponds

UK researchers exhume a pond to study how much carbon aquatic features like these can take in, and how quickly. Photo courtesy of Michael Jeffries.

Forests, grasslands, wetlands, and other vegetated habitat types take in large amounts of carbon that is then stored in plant tissue and sediment – carbon that would otherwise exist in the atmosphere as a greenhouse gas. But there is little consensus about how much carbon can be stored in lakes and ponds (and how quickly it can be stored, and for how long). Researchers from the University of Northumbria and from the University of Highlands and Islands dug out thirty small ponds in a former coal mine in the UK and measured how much organic carbon the ponds accumulated over an 18- to 20-year period. They found that over 20 years, the ponds acted as carbon “sinks” and had higher rates of organic carbon burial than many other terrestrial and aquatic habitats, including boreal and temperate forests and temperate grasslands.  

Author Contact: Michael Jeffries (michael.jeffries@northumbria.ac.uk)

  • Taylor S, Gilbert PJ, Cook DA, et al. High carbon burial rates by small ponds in the landscape Frontiers in Ecology and the Environment. DOI: 10.1002/fee.1988

 

Machine-learning shows that ecology is shifting to data-intensive research and anthropogenic themes

The discipline of ecology is changing quickly to accommodate shifting societal needs and to make room for new areas of interest, but the vast breadth of research being published makes it difficult to quantify exactly how – and how much – it is really changing. Today, software can learn from data, identify patterns, and make decisions with minimal human intervention – a concept dubbed “machine-learning.” Automated content analysis, or ACA, is a machine-learning method that “trains” a program or model to identify key concepts and themes across large amounts of text. Researchers from Purdue University in Indiana asked their ACA software to “read” over 80,000 papers published in the ecological literature between 1980 and 2016 and to identify the key concepts and themes in each. The researchers then analyzed how the prevalence of various themes has changed over time, and found that theoretical research and articles on plant and population ecology are becoming less common, while articles about microbial ecology, genetics, biogeochemistry, macrosystems ecology, and human dimensions of nature are becoming more common.

Author Contact: Songlin Fei (sfei@purdue.edu)

  • McCallen E, Knott J, Nunez-Mir G, et al. Trends in ecology: shifts in ecological research themes over the past four decades. Frontiers in Ecology and the Environment. DOI: 10.1002/fee.1993

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org.

Birds can mistake some caterpillars for snakes; can robots help? 

Researchers observe a defense mechanism for caterpillars can attract unwanted attention

December 17, 2018 
For Immediate Release  

Contact: Zoe Gentes, 202-833-8773 ext. 211, zgentes@esa.org 

 

During the night, this caterpillar (Oxytenis modestia) moved onto and began feeding on a leaf directly above the nest of a rufous-tailed hummingbird (Amazilia tzacatl), whose comings and goings disturbed the caterpillar, causing it to expand and reveal its “eyes” and rear up into its snake-mimic posture. Photo courtesy of James Marden.

When a caterpillar disguises itself as a snake to ward off potential predators, it should probably expect to be treated like one. 

This is exactly what happened in Costa Rica earlier this year, when researchers witnessed a hummingbird defending its nest from what it interpreted to be a snake, but was actually a larva of the moth Oxytenis modestia. The encounter is described in a new paper published in the Ecological Society of America’s journal Ecology

These moths — sometimes called the dead-leaf moth or the Costa Rica leaf moth — resemble flat dried leaves as adults. The caterpillars can inflate the top of their heads to expose a pair of eyespots. When disturbed, they raise their head up and move from side to side, increasing the snake-like appearance. In particular they resemble a green parrot snake, known to prey on nesting birds. 

The attacking hummingbird’s nest with eggs was about 10cm away from the caterpillar in a small tree. When the researchers went to look for an assumed snake, they instead found the caterpillar feeding on a leaf immediately above the nest. 

“Hummingbirds have a few stereotypical styles of flying: visiting flowers, preying on swarms of tiny insects, chasing each other, and mating/territorial display flights,” says lead author James H. Marden, professor with the Department of Biology at Pennsylvania State University. “Mobbing behavior directed against a threat to their nest is much less common but distinct and easy to recognize if you know their other flight behaviors… One can recognize this from a distance and only notice the source of their agitation upon close inspection.” 

Caterpillars and adults of a variety of butterflies and moths have eye-like spots that deter potential predators. Observations of how these eyespots affect animal interactions in natural settings are extremely rare. 

The interaction took place on a strip of secondary growth between the Pacific and primary rainforest on the Osa Peninsula, Costa Rica. The authors believe that the comings and goings of the female rufous-tailed hummingbird (Amazilia tzacatl) around its nest may have disturbed the caterpillar, causing it to expose its eyespots, which in turn prompted the hummingbird to defend its nest using what is referred to as ‘mobbing behavior’ by birds — darting flights and pecking at a threat, commonly snakes. 

The caterpillar was unable to feed during the 26-minutes of nearly continuous attacks. Most of the bird’s movements were cautious and exploratory, but included quick thrusts to peck or bite the eyespots (view video clip here).  

Marden stated that it was difficult for either the bird or caterpillar to disengage from the standoff, with the hummingbird protecting its nest and the caterpillar just trying to finish its leafy meal. “A snake-like creature so near to its nest was too much of a distraction or threat to ignore for very long,” he explained. “The caterpillar seemed more irreversibly committed. When a camouflaged animal reveals itself as threatening, it is committed and cannot easily go back to camouflage. Hence, I think that it had no choice but continue looking like a snake until the threat had passed.”  

A bite directly on the false eye. Photo courtesy of James Marden.

Eventually the caterpillar gave up on eating and crawled away while still under attack, and the hummingbird resumed normal nesting behavior.  

When birds exhibit this mobbing behavior targeting snake’s eyes, it often ends with snakes being killed by repeated bites and pecks near the head and collar area. As for creatures that mimic snakes to protect themselves from being eaten, can they in turn protect themselves from this mimicry backfiring, such as in this encounter? Because the hummingbird behavior was typical anti-snake behavior, it can be considered replicable. 

Marden is fascinated by this interaction, and he believes future studies of this behavior can be conducted using a tiny, caterpillar robot to experiment with eyespots. 

“You’d want a cylindrical shape and green color, with the ability to rear up in the front and reveal an eyespot,” he outlines. It should be remote controlled, light enough to attach to a leaf or stem, and wireless. “Many experiments have done this with clay or similar material, but those models lack the ability to combine eyespots with movement and behavior. That is what a robot could add.” 

When disturbed, the caterpillar increases its internal pressure, causing the area behind the head to expand and expose a pair of eyespots. Expansion and exposure of the “eyes” is accompanied by rearing up and side to side movements, which closely mimic a small snake. Photo courtesy of James Marden.

With such a robot, researchers could vary the eye-like nature and contrast of spots on the head of the robot to test various responses of nest-defending birds. A study like this could definitively test the effects of eye-like versus other mimicry patterning for provoking or repelling defensive attacks. 

The day following the initial encounter, the researchers found the caterpillar feeding on a leaf on the same plant, as far away from the nest as possible. It had some marks by the edge of the right eyespot that may be beak marks – apparently the caterpillar learned its lesson. 


 

Journal Article 

Marden, J.H., J.F.P. Carillo. 2018. “Anti‐predator behavior by a nesting hummingbird in response to a caterpillar with eyespots.” Ecology. DOI: 10.1002/ecy.2582

Authors 
James H. Marden, Department of Biology, Pennsylvania State University  
José Freiner Perez Carillo, Campanario Biological Station, Osa Peninsula, Costa Rica 

Author contact 
James H. Marden       jhm10@psu.edu 

 

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The Ecological Society of America (ESA), founded in 1915, is the world’s largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 9,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society’s Annual Meeting attracts 4,000 attendees and features the most recent advances in the science of ecology. Visit the ESA website at http://www.esa.org