Constantine Alexander's Journal

Wind turbines have minor impact on small-bird populations

By Science for Environment Policy

Only about two or three small birds are killed by wind turbines each year for every 225-300 houses supplied with renewable energy, new research suggests. The study collated data from 116 US and Canadian studies on 156 species of passerines (small birds). The study suggests some species are affected more than others, but that wind turbines generally have only a minor impact on these small-bird populations.

Wind turbines currently supply around 8% of Europe's electricity, providing over 117 gigawatts of installed capacity¹ of wind energy. However, wildlife groups are concerned about wind turbines killing large numbers of birds. More than half of all bird species are passerines and they are the most frequently killed. Until now, there have been no comprehensive studies collating research on small-bird collisions at wind farms.

The researchers wanted to provide regulators, the wind industry and conservation bodies with a better understanding of collision rates in these populations. They analysed data from 116 studies, the majority (70%) of which provided data specifically on small-bird fatalities. For the remaining 35 studies, they estimated small-bird fatalities based on data on all birds killed.

The results suggest that, on average, 2.10-3.35 small birds are killed each year per megawatt (MW) of installed capacity of wind turbines. A 1 MW turbine on land can power about 225-300 houses. In total, the researchers estimate that between 134 000 and 230 000 small birds are killed annually by turbines across all of the US and Canada.

By contrast, over six million small birds are thought to be killed by communication towers in these two countries. Meanwhile, cats are estimated to kill at least 55 million birds each year in the UK alone, although some of these are thought to be weaker birds that would die anyway.

Small birds accounted for nearly 63% of all birds killed at wind facilities. But of 24 families of birds, just six accounted for almost half of all those killed. These were larks (Alaudidae), wood-warblers (Parulidae), vireos (Vireonidae), blackbirds or orioles (Icteridae), sparrows (Emberizidae) and kinglets (Regulidae). However, these losses equated to less than 0.1% of North American populations each year – even for the worst affected bird species.

At the species level, the most commonly killed small birds were the shore or horned lark (Eromophilia alpetris), red-eyed vireo (Vireo olivaceus) and western meadowlark (Sturnella neglecta). Overall, 22% of all small birds that collided with wind turbines were shore larks. The global shore lark population is large and widespread, so the birds are not considered under threat, though their numbers have declined in recent decades.

It is difficult to produce completely accurate data on bird collisions for a number of reasons. For example, fatalities can only be counted if carcasses are discovered by 'searchers' and some carcasses are scavenged by predators before discovery. Equally, some birds that were not killed by wind turbines may be incorrectly counted. However, equations called 'estimators' have been developed to adjust for these biases. The researchers used four different estimators to gain a more accurate picture of bird collisions than in previous studies.

The researchers also explored evidence for factors thought to contribute to bird collisions. They found no evidence that taller turbines killed more birds, but some evidence that older facilities did, although they did not discuss exactly why this might be.

1. The maximum number of watts of electricity that can be produced in one hour. For wind turbines, this assumes optimal wind conditions.

Citation: Erickson, W. P., Wolfe, M. M., Bay, K. J. et al. (2014). A comprehensive analysis of small-passerine fatalities from collision with turbines at wind energy facilities. PloS ONE. 9(9), e107491. DOI:10.1371/journal.pone.0107491. 

Contact: W. P. Erickson

 

Wind turbine risks to seabirds: new tool maps birds' sensitivity to offshore farms

The Swedish offshore wind farm Lillgrund in the Øresund between Malmö and Copenhagen. For the Lillgrund project Siemens installed 48 SWT-2.3-93 wind turbines each rated at 2.3 megawatts (MW). The wind farm with a total installed capacity of 110 MW is operated by the Swedish utility Vattenfall and officially came on line in June 2008. The Lillgrund offshore wind farm produces enough electrcity to supply 60,000 Swedish households. 

By Science for Environment Policy

A new tool has been developed to map the sensitivity of seabirds to offshore wind farm development. The Seabird Mapping and Sensitivity Tool (SeaMaST), currently for use in English waters, combines information on the sensitivity of seabird species to wind turbines with data on the birds' distributions. It provides maps that can be used for both the offshore wind farm industry and marine spatial planning.

In an effort to mitigate climate change, the EU aims to source 20% of its energy from renewables by 2020. As a result, many Member States are investing heavily in wind power, with offshore wind farms especially important in some countries.

However, offshore wind turbines can have damaging effects on seabirds: the birds can collide with the turbines and they may lose important feeding grounds by avoiding the turbines. Seabird populations also may be particularly vulnerable to additional sources of mortality as many species do not start breeding for several years and then raise relatively few offspring each year. Therefore, in order to achieve the dual EU aims of increasing the share of renewables and halting declines in biodiversity, offshore wind farms must be carefully sited to minimise these impacts.

To aid this process, researchers developed the mapping tool SeaMaST. They used two main sources of data to map the densities of seabird species in English waters: the European Seabirds at Sea database (which includes over 310 000 seabird records from 1979 to 2011) and data collected by the Wildfowl & Wetlands Trust (which covers 400 000 seabird records from surveys carried out between 2001 and 2011).

The densities were mapped onto 3 km x 3 km grid squares. The researchers were also able to map measures of certainty regarding the data, a particularly useful feature of the tool, as this can be important for decision making.

The sensitivity of the seabird species to wind turbines was scored using four factors that reflect the species conservation importance and six factors related to behaviour. Conservation importance was based on: status in relation to the Birds Directive, percentage of the population that occurs in English territory, adult survival rate and UK threat status.

The behavioural factors used included: flight altitude (with those flying at the height of turbine blades given the highest ranking), flight manoeuvrability, percentage of time spent flying, nocturnal flight activity, disturbance by wind farm structures and ship and helicopter traffic, and habitat specialisation.

From these rankings, the researchers produced two 'Species-specific Sensitivity Indices'. The first index shows sensitivity to collision; species with low flight manoeuvrability and which spend a lot of time flying at the height of the turbine blades, for instance, would have a high score in this index. Under the second index, which shows sensitivity due to displacement, species that would lose large amount of habitat through avoiding wind farms would score highly.

Both indices were then combined with data on seasonal abundances (excluding areas where the data were associated with low certainties) to produce robust maps of seabird sensitivity to wind turbines. Now available to UK marine planners, SeaMaST is valuable for a number of different purposes, the researchers say. For example, it can be used to provide evidence for Environmental Impact Assessments or to inform new Marine Protection Areas. Furthermore, the tool provides a framework which can be used with other data to map seabird sensitivity in other countries or across other sectors, such as wave and tidal energy, dredging or fishing.

Citation: Bradbury, G., Trinder, M., Furness, B. et al. (2014). Mapping Seabird Sensitivity to Offshore Wind Farms. PLoSONE. 9(9): e106366. DOI: 10.1371/journal.pone.0106366.

Contact: Gareth Bradbury

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Exploring the Deep Sea with Dr. Sylvia Earle

 

 Dr. Sylvia Earl. Credit: (c) Kip Evans/Mission Blue

Formerly chief scientist of NOAA, Dr Sylvia Earle is the founder of Deep Ocean Exploration and Research, Inc., founder of Mission Blue and SEAlliance, and chair of the Advisory Councils of the Harte Research Institute and the Ocean in Google Earth. She has a B.S. degree from Florida State University, M.S. and PhD. from Duke University, and 22 honorary degrees. She has authored more than 190 scientific, technical, and popular publications; lectured in more than 80 countries; and appeared in hundreds of radio and television productions.

Dr Earle has led more than a hundred expeditions and logged more than 7,000 hours underwater, including leading the first team of women aquanauts during the Tektite Project in 1970; participating in ten saturation dives, most recently in July 2012; and setting a record for solo diving in 1,000-meter depth. Her research concerns marine ecosystems with special reference to exploration, conservation, and the development and use of new technologies for access and effective operations in the deep sea and other remote environments.

 

Toolkit for ocean health

The ocean is undergoing global changes at a remarkable pace and we must change with it to attain our best possible future ocean, warns the head of The University of Western Australia's Oceans Institute.

One of the global leaders in ocean science, Professor Carlos Duarte has shared his insights on the future of the world's oceans in a paper published in the international open-access journal Frontiers in Marine Science. In the paper Professor Duarte explains the grand challenge researchers face in addressing global change and the future state of the ocean.

"The ocean is under significant impact by anthropogenic global pressures such as ocean acidification, warming, overfishing and pollution, resulting from the impact of human activity on major processes that regulate the functions of the planet," he said.

"Dependence on resources including water, energy and key elements has prompted a suite of changes at the global scale and we are now facing the impacts of climate change, a loss of biodiversity and deteriorating water quality.

"While human pressures such as overfishing have occurred for almost 200,000 years, the cumulative impact of these combined pressures in recent years is now significantly influencing ocean health through unprecedented pressures.

"Consequently, planning of infrastructure, resource management, industry operations and conservation policies all require the capacity to anticipate change and forecast the likely properties of the future ocean."

Professor Duarte explained that a number of conclusions can be forecast by analysing current ocean trends.

"By the end of the twenty-first Century the oceans will be warmer, with a reduced ice extent, higher sea levels, more acidic and with somewhat lower oxygen levels than at present," he said.

"Research effort must be directed to understanding the responses of marine systems to these multiple, cumulative pressures."

Professor Duarte advises that policy makers, the public and the scientific community should accept change as a prerequisite to manage it. He emphasises the need for partnerships to frame research findings in effective ways and foster widespread action.

"Close cooperation between these groups is needed to progress our capacity to manage ocean problems adaptively," Professor Duarte said.

"The future ocean will be, no doubt, different in many ways from the ocean we enjoy today, but we can still direct that change. In order to get back behind the steering wheel the goals of policy makers, the public and scientists must converge to guide this change in order to achieve our best possible future ocean."

Professor Duarte was recently appointed Editor-in-Chief of the newly launched journal and will maintain a position with the UWA as an Adjunct Professor following his departure from the UWA Oceans Institute. The UWA Oceans Institute strives to deliver ocean-based solutions for humanity's grand challenges.

Citation: Carlos M. Duarte. Global Change and the Future Ocean: A Grand Challenge for Marine Sciences. Frontiers in Marine Science, November 2014 DOI: 10.3389/fmars.2014.00063.

• The UWA Oceans Institute brings together the strength of UWA's researchers into a multidisciplinary, integrated research focus. The goal is to capitalise on UWA's existing research strengths- in areas such as oceanography, ecology, engineering, resource management and governance-and utilise them to deliver ocean solutions for humanity's grand challenges.
• Frontiers is a community-driven open-access publisher and research networking platform. Established by scientists in 2007, Frontiers drives innovations in peer-review, article level metrics, post publication review, democratic evaluation, research networking and a growing ecosystem of open-science tools. The "Frontiers in" journal series has published 25,000 peer-reviewed articles across 49 journals, which receive 6 million monthly views, and are supported by over 160,000 leading researchers worldwide. In 2014, Frontiers won the ALPSP Innovation in Publishing Award.

Contact: David Stacey
61-864-883-229
Frontiers

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Better forecasts for sea ice under climate change

University of Adelaide-led research will help pinpoint the impact of waves on sea ice, which is vulnerable to climate change, particularly in the Arctic where it is rapidly retreating.

Published today in the Proceedings of the Royal Society A, the research reports the first laboratory experiments testing theoretical models of wave activity in frozen oceans.

"Sea ice is both an indicator and agent of climate change," says project leader Dr Luke Bennetts, Research Fellow in the School of Mathematical Sciences.

"Sea ice covering the ocean surface is white and efficiently reflects the sun's rays, keeping the oceans cool. When it melts it reveals the dark ocean beneath, which absorbs the solar radiation and becomes warmer - and that, of course, further weakens the ice.

"Waves break up the ice so that it melts more easily. In addition, exposing larger areas of the ocean surface provides a larger area for the wind to generate waves, which further promotes the breaking."

To date, however, climate models haven't included the impact of waves on sea ice.

In collaboration with Dr Tim Williams, of the Nansen Environment and Remote Sensing Centre in Bergen, Norway, and Professor Dany Dumont, of the University of Quebec in Canada, Dr Bennetts conducted experiments modelling ocean waves travelling through ice floes in a wave basin and measuring the wave energy.

"Wave energy is scattered by ice floes and is transferred into collisions between ice floes and into waves running over the tops of the floes, both of which impact the ice cover," Dr Bennetts says.

"Wave-ice interactions occur over hundreds of kilometres into the ice-covered ocean. We need to develop models that predict the distances waves will penetrate so we can determine which regions of sea ice are more susceptible to breaking up.

"Regional variability in sea ice is presently not very well understood, with models under-predicting the extent of Antarctic sea ice and over-predicting the extent in the Arctic. Our research will lead to better physics in climate models and hopefully help answer these questions (among others).

"We need to take into account the impact of waves to accurately forecast future scenarios for sea ice."

Citation: Luke Bennetts and Timothy Williams; Water wave transmission by an array of floating disks; Proceedings of the Royal Society A (2014); DOI: 1098/rspa.2014.0698.

Contact: Luke Bennetts
61-466-457-406
University of Adelaide

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CT scans of coral skeletons reveal ocean acidity increases reef erosion

This is an image of µCT scan showing the outside (top) and inside (bottom) of an experimental coral block after a one-year deployment in Kāne'ohe Bay, Hawai'i. Note the bioerosion scars inside the block. Credit: Nyssa Silbiger at UH Mānoa and Mark Riccio at the Cornell Unversity µCT Facility for Imaging and Preclinical Research.

Coral reefs persist in a balance between reef construction and reef breakdown. As corals grow, they construct the complex calcium carbonate framework that provides habitat for fish and other reef organisms. Simultaneously, bioeroders, such as parrotfish and boring marine worms, breakdown the reef structure into rubble and the sand that nourishes our beaches. For reefs to persist, rates of reef construction must exceed reef breakdown. This balance is threatened by increasing atmospheric carbon dioxide, which causes ocean acidification (decreasing ocean pH). Prior research has largely focused on the negative impacts of ocean acidification on reef growth, but new research this week from scientists at the Hawai'i Institute of Marine Biology (HIMB), based at the University of Hawai'i - Mānoa (UHM), demonstrates that lower ocean pH also enhances reef breakdown: a double-whammy for coral reefs in a changing climate.

To measure bioerosion, researchers deployed small blocks of calcium carbonate (dead coral skeleton) onto the reef for one year. Traditionally, these blocks are weighed before and after deployment on the reef; however, HIMB scientists used microCT (a high-resolution CT scan) to create before and after 3-D images of each block. According to Nyssa Silbiger, lead author of the study and doctoral candidate at HIMB, this novel technique provides a more accurate measurement of accretion and erosion rates.

The researchers placed the bioerosion blocks along a 100-ft transect on shallow coral reef in Kāne'ohe Bay, Hawai'i, taking advantage of natural variability of pH in coastal reefs. The study compared the influence of pH, resource availability, temperature, distance from shore, and depth on accretion-erosion balance. Among all measured variables, pH was the strongest predictor of accretion-erosion. Reefs shifted towards higher rates of erosion in more acidic water - a condition that will become increasingly common over the next century of climate change.

 

This study also highlights the impact of fine-scale variation in coastal ocean chemistry on coral reefs. Current models from the International Panel on Climate Change (IPCC) predict changes in pH for the open ocean, but these predictions are problematic for coral reefs, which are embedded in highly variable coastal ecosystems. The study found dramatic differences in ocean pH and in the daily variability of pH across a short distance.

"It was surprising to discover that small-scale changes in the environment can influence ecosystem-level reef processes," said Silbiger. "We saw changes in pH on the order of meters and those small pH changes drove the patterns in reef accretion-erosion."

Silbiger and colleagues are learning all they can from the microCT scans, as this is the first time before-and-after microCT scans were used as a measure of accretion-erosion on coral reefs. In ongoing work, they are using this technology to distinguish between accretion and erosion and to single out erosion scars from specific bioeroder groups (e.g., holes from boring worms versus bioeroding sponges). The researchers are also using this technology to investigate the drivers of the accretion-erosion balance over the much larger area of the Hawaiian Archipelago.

Citation: NJ Silbiger, Ò Guadayol, FIM Thomas, MJ Donahue. Reefs shift from net accretion to net erosion along a natural environmental gradient. Marine Ecology Progress Series, 2014; 515: 33 DOI: 10.3354/meps10999.

Contact: Marcie Grabowski
808-956-3151
University of Hawaii ‑ SOEST

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Sucessful test of SeaBed give scientists a powerful tool to study the changes occurring in sea-ice extent

SeaBED was deployed from the British research vessel James Clark Ross. Credit: Hanumant Singh / Woods Hole Oceanographic Institution.

A National Science Foundation (NSF)-funded research team has successfully tested an autonomous underwater vehicle, AUV, that can produce high-resolution, three-dimensional maps of Antarctic sea ice. SeaBED, as the vehicle is known, measured and mapped the underside of sea-ice floes in three areas off the Antarctic Peninsula that were previously inaccessible.

The results of the research were published this week in the journal Nature Geoscience. Scientists at the Institute of Antarctic and Marine Science (Australia), Antarctic Climate and Ecosystem Cooperative Research Centre (Australia), Woods Hole Oceanographic Institution (USA) and British Antarctic Survey (U.K.) jointly carried out the project.

Ted Maksym, an NSF-funded researcher at Woods Hole and co-author of the Nature paper, said the successful SeaBED deployment is an important first step toward making the kinds of routine underwater measurements needed to help monitor and understand large-scale changes in sea ice.

"What this effort does is show that observations from AUVs under the ice are possible and there is a very rich data set that you can get from them," he said. "This work is an important step toward making the kinds of routine measurements we need in order to really monitor and understand what's happening with the ice and the large scale changes that are occurring."

While most oceanographic survey instruments look down at the seafloor, SeaBED's upward-looking sonar allowed it to map under the ice, said Woods Hole engineering scientist Hanumant Singh, whose lab designed, built and operated the AUV.

The AUV operated at a depth of 20 to 30 meters (65 to 98 feet) and was driven in a "lawnmower pattern." These lines of data were merged to form high-resolution 3-D bathymetric surveys of the underside of the ice. The yellow SeaBED robot, which is approximately two meters (six feet) long and weighs nearly 200 kilograms (440 pounds), has a twin-hull design that gives the robot enhanced stability for low-speed photographic surveys.

"Putting an AUV together to map the underside of sea ice is challenging from a software, navigation and acoustic communications standpoint," said Singh.

"SeaBED's maneuverability and stability made it ideal for this application where we were doing detailed floe-scale mapping and deploying, as well as recovering in close-packed ice conditions," he added. "It would have been tough to do many of the missions we did, especially under the conditions we encountered, with some of the larger vehicles."

NSF supported the development and deployment of SeaBED to advance the state-of-the-art of these ocean-going instruments as remote sensors in extreme environments.

 

Scientists use a range of technologies and techniques to measure sea ice thickness. Satellite observations can measure large-scale thickness from space, but interpreting the data accurately can be difficult due to snow cover on the ice. Measurements made on the sea ice by drilling holes, together with visual observations from ships are critical for building a more complete picture, but difficulties in getting access to thicker areas of sea ice leave gaps in the data. Now, with the SeaBED, scientists have an invaluable new tool to fill this gap.

Citation: G. Williams, T. Maksym, J. Wilkinson, C. Kunz, C. Murphy, P. Kimball & H. Singh; Thick and deformed Antarctic sea ice mapped with autonomous underwater vehicles; Nature Geoscience (2014); DOI:10.1038/ngeo2299.

Contact: Peter West
703-292-7530
National Science Foundation

Biology trumps chemistry in open ocean

New framework advances understanding of phytoplankton nutrient assimilation

Single-cell phytoplankton in the ocean are responsible for roughly half of global oxygen production, despite vast tracts of the open ocean that are devoid of life-sustaining nutrients. While phytoplankton's ability to adjust their physiology to exploit limited nutrients in the open ocean has been well documented, little is understood about how variations in microbial biodiversity -- the number and variety of marine microbes - affects global ocean function.

In a paper published in PNAS on November 24, scientists laid out a robust new framework based on in situ observations that will allow scientists to describe and understand how phytoplankton assimilate limited concentrations of phosphorus, a key nutrient, in the ocean in ways that better reflect what is actually occurring in the marine environment. This is an important advance because nutrient uptake is a central property of ocean biogeochemistry, and in many regions controls carbon dioxide fixation, which ultimately can play a role in mitigating climate change.

"Until now, our understanding of how phytoplankton assimilate nutrients in an extremely nutrient-limited environment was based on lab cultures that poorly represented what happens in natural populations," explained Michael Lomas of Bigelow Laboratory for Ocean Sciences, who co-led the study with Adam Martiny of University of California - Irvine, and Simon Levin and Juan Bonachela of Princeton University. "Now we can quantify how phytoplankton are taking up nutrients in the real world, which provides much more meaningful data that will ultimately improve our understanding of their role in global ocean function and climate regulation."

To address the knowledge gap about the globally-relevant ecosystem process of nutrient uptake, researchers worked to identify how different levels of microbial biodiversity influenced in situ phosphorus uptake in the Western Subtropical North Atlantic Ocean. Specifically, they focused on how different phytoplankton taxa assimilated phosphorus in the same region, and how phosphorus uptake by those individual taxa varied across regions with different phosphorus concentrations. They found that phytoplankton were much more efficient at assimilating vanishingly low phosphorus concentrations than would have been predicted from culture research. Moreover, individual phytoplankton continually optimized their ability to assimilate phosphorus as environmental phosphorus concentrations increased. This finding runs counter to the commonly held, and widely used, view that their ability to assimilate phosphorus saturates as concentrations increase.

"Prior climate models didn't take into account how natural phytoplankton populations vary in their ability to take up key nutrients, "said Martiny. "We were able to fill in this gap through fieldwork and advanced analytical techniques. The outcome is the first comprehensive in situ quantification of nutrient uptake capabilities among dominant phytoplankton groups in the North Atlantic Ocean that takes into account microbial biodiversity. "

Citation: Michael W. Lomas, Juan A. Bonachela, Simon A. Levin, and Adam C. Martiny; Impact of ocean phytoplankton diversity on phosphate uptake; PNAS (2014); DOI: 10.1073/pnas.1420760111.

Contact: Darlene Crist
207-315-2567 x103
Bigelow Laboratory for Ocean Sciences

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Mediterranean meteorological tide has increased by over a millimetre a year since 1989

Les Rotes beach in Denia (Alicante, Spain).

A new database developed by the University of Cantabria (Spain) provides data on sea level variation due to atmospheric changes in the south of Europe between 1948 and 2009. Over the last two decades sea levels have increased in the Mediterranean basin.

"The meteorological sea level or meteorological tide component is the variation of the sea level as a result of atmospheric changes or more specifically, changes in the atmospheric pressure and the wind at the sea surface," Alba Cid explains to SINC, Alba being the lead author of the study published in the journal 'Climate Dynamics' which analyses 62 years' worth of data for this sea level component.

Cid and her team at the Environmental Hydraulics Institute at the University of Cantabria (Spain) have generated two (long-term and high resolution) time series for meteorological tides in the Atlantic and Mediterranean basins in the south of Europe and the Canary Islands.

In total, they have analysed the trends from 1948 to 2009, reflected in a new Global Ocean Surges (GOS) database. The simulation tool used is the numeric Regional Ocean Modelling System (ROMS) developed by the University of Rutgers (USA).

The results are very different depending on the period. "The trends from 1948 to 1989 are very small and negative in all of the area analysed, which means that the meteorological tide has decreased during this time period," points out Cid.

On the African coast of the Atlantic, the Adriatic coast and the north-east of the Eastern basin, the meteorological component to sea level has decreased by 0.35 millimetres for every year during this period. The trends are weaker on the Spanish coast of the north Atlantic and along the African coast in the Eastern basin of the Mediterranean.

However, over the last two decades, from 1989 to 2009, the trends are positive, or rather sea levels have increased, and to a greater degree. The tides present values of less than 0.5 mm per year in the Atlantic basin and more than 1 mm a year in several areas of the Mediterranean coast.

The GOS database also differentiates between summer and winter in each time series. According to the study, the trends observed in winter are negative in the areas analysed. The decrease in sea levels is more obvious (1mm per year) in the centre of the Mediterranean and the Adriatic Sea.

The sea level rises in summer, especially in the North Atlantic, the Spanish coast of the Mediterranean and the Tunisian coast. "Although negative trends of 0.3 mm a year can also be observed during this season along the African coast of the Atlantic," the researchers highlight from the study.

Hourly data for 62 years

To validate the results of the numerical simulations, the researchers have compared the data generated every hour from 1948 to 2009 in 58 coastal locations in Spain, Portugal, France, Italy and the Canary Islands, with real data measured by tide gauges and satellites. "The results have allowed us to calculate these long-term trends," adds Cid.

From this work and the data described in the article, the investigators are now analysing the most extreme levels and their relation to climate patterns, such as for example the North Atlantic oscillation (NAO). "We will shortly be publishing an article with the results obtained," concludes the lead author.

Citation: Alba Cid, Sonia Castanedo, Ana J. Abascal, Melisa Menéndez, Raúl Medina; A high resolution hindcast of the meteorological sea level component for Southern Europe: the GOS dataset; Climate Dynamics, 2014; 43 (7-8): 2167 DOI: 10.1007/s00382-013-2041-0.

Contact: SINC
34-914-251-820
FECYT - Spanish Foundation for Science and Technology

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Wild food is an important ecosystem service, study argues

By Science for Environment Policy

Wild plants and animals consumed as food provide an important ecosystem service that deserves more policy attention, claims a recent study. To support their argument, the researchers gathered data which show the significance of wild food to European traditions, cultural identity and recreation.

Many countries around the world are creating maps of their ecosystem services to support environmental policy. However, wild food – which includes everything from foraged blueberries to hunted deer – rarely appears on these maps. This is despite the fact that most ecosystem service classification systems, such as the Millennium Ecosystem Assessment and TEEB assessments, consider wild food as a subcategory of 'provisioning' services, which supply some form of material or energy output. This study's authors, funded by the EU's BiodivERsA programme¹, suspect that it is being omitted either as a result of lack of data or the belief that it is unimportant.

To investigate wild food's importance, they gathered data on the availability, use and benefits of wild game, mushrooms and other plants (such as fruit and herbs) in the EU. The data came from a range of sources, including previous studies, hunting and consumption statistics, and biodiversity databases. The researchers even studied cookbooks to understand the role of specific food items in traditional cuisines.

They focused on wild food at the EU scale because many policies that affect ecosystem services are developed at this level, such as the Common Agricultural Policy and the Biodiversity Strategy to 2020. They excluded fish from their study, as well as plants gathered for other purposes, such as medicinal use.

They identified a total of 38 animals, 152 mushrooms and 592 plants that are gathered from the wild in the EU. Over 100 million people (20% of the EU population) consume wild food, they estimate, and 65 million (14%) collect some form of wild food themselves at least occasionally. Around 13 million of these hunt (2.7%). There is lower consumption of wild food in countries such as the Netherlands, Denmark and Hungary, for instance, where early agriculture ended such traditions long ago.

Generally, wild food only accounts for a very small fraction of total food consumed, but this is not always the case. For example, an estimated 55-60% of Finnish people collect wild berries, which account for up to 34% of fruit consumed in Finland. Over 6.5% of meat eaten in France is wild game.

While there are nutritional and economic benefits of wild food, its cultural assets may be most significant – and more difficult to substitute. For this reason, the researchers suggest that wild food may be better classified as a cultural, rather than provisioning, service.

For many people, gathering wild food is a fun opportunity to get in touch with nature and spend time with family. Many people also consider collecting and eating wild foods to be an important way of expressing their cultural heritage, and these foods may be central to national cuisines. Although wild food is generally on the decline in Europe, there has been a recent surge in interest among those living in cities, in response to increasing industrialisation and globalisation.

Wild food is not without controversy, and it is important to balance demand with conservation. However, policymakers could potentially manage landscapes to increase wild food abundance and the value of the landscapes themselves.

The data on wild food collection and use are patchy, particularly because much of it is informal. The researchers therefore stress that this is the best available data, while highlighting gaps for various countries and foods.

1. BiodivERsA is supported by the European Commission under the Seventh Framework Programme.  This study also received financial contributions and Practice), also supported from VOLANTE (Visions of Land Use Transitions in Europe) and OPERAs (Ecosystem Science for Policy by the European Commission under the Seventh Framework Programme. 

Citation: Schulp, C.J.E., Thuiller, W. & Verburg, P.H. (2014). Wild food in Europe: A synthesis of knowledge and data of terrestrial wild food as an ecosystem service. Ecological Economics. 105: 292–305. DOI: 10.1016/j.ecolecon.2014.06.018.

Contact: Nynke Schulp

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