New article: Predicting the future effectiveness of protected areas for bird conservation in Mediterranean ecosystems under climate change and novel fire regime scenarios

Global change challenges traditional conservation approaches based on the selection of static protected areas due to their limited ability to deal with the dynamic nature of driving forces relevant to biodiversity. The Natura 2000 network (N2000) constitutes a major milestone in biodiversity conservation in Europe, but the degree to which this static network will be able to reach its long-term conservation objectives raises concern.

In this work, recently published in Diversity and Distribution, we have evaluated, in collaboration with Antoine Guisan’s lab (Department of Ecology and Evolution, University of Lausanne), ICO (Catalan Institute of Ornithology) and EBCC (European Bird Census Council), the future changes in the effectiveness of N2000 in a Mediterranean ecosystem between 2000 and 2050 under different combinations of climate and fire-induced land cover change scenarios. To our knowledge, the present study is one of the most ambitious attempts so far to forecast biodiversity changes (i.e. multispecies responses) based on simulations of future vegetation dynamics and fire disturbance under climate change in a fire-prone Mediterranean region.

Our findings show that although the future response of the species to these changes is species specific, large decreases in the amount of optimal habitats are expected for most of the species. In addition, our results also indicate that such a decrease in habitat suitability will be driven by both climate and land cover changes. Interestingly, the response of a high number of species to these changes is predicted to vary substantially depending on the fire management practices that will be implemented in the future. Our results also provide the first assessment of the future effectiveness of the currently established protected areas for the conservation of bird species targeted by N2000 under different combinations of climate and novel fire regime scenarios.

This study offers novel insights into how fire management policies in interaction with land abandonment and climate change might strongly impact on future biodiversity conservation in fire-prone Mediterranean ecosystems. We also emphasize the need for an integrative and proactive conservation perspective wherein agricultural, forest and fire management policies should be considered inside and outside N2000 to effectively maintain key habitats for threatened birds in these types of ecosystems. In the light of our results, we underline the need for an explicit consideration of landscape dynamics when forecasting the future effectiveness of a network of protected areas in a context of global change.

Regos, A., D’Amen, M., Titeux, N., Herrando, S., Guisan, A., Brotons, L., 2015. Predicting the future effectiveness of protected areas for bird conservation in Mediterranean ecosystems under climate change and novel fire regime scenarios. Divers. Distrib. doi:10.1111/ddi.12375

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New article: Optimising long-term monitoring projects for species distribution modelling. How atlas data may help

In this work, recently published in Ecography, we provide a method based on modern atlas data to guide the establishment of monitoring projects that will deliver useful data to build accurate distribution models. Long-term monitoring data are used to evaluate population trends, but they may also be integrated in spatial models to produce detailed species distribution maps at large spatial scales. However, sampling design has a strong impact on the predictive accuracy of distribution models and this issue is to be addressed when using this type of data.

We examined how the number of sampling sites influences the predictive accuracy of the models and we determined the minimum number of sites required to generate reliable spatial models as a direct output of monitoring projects. To do this, we calibrated large-scale, fine-resolution distribution models for 20 bird species using data collected during the ‘Breeding Bird Atlas of Wallonia’ (BBAW) project. Modern atlas projects like BBAW provide data that are analogous to monitoring data. We manipulated the amount of calibration data to represent a range of sampling coverage and we used independent evaluation data to calculate modeling performance parameters.

The modeling performance was sensitive to particularly small sample sizes and reached an asymptotic level beyond a fairly large sampling coverage. This asymptotic level varied considerably among species depending mainly on their prevalence. Our results suggest that a sampling coverage of 4-5% of the study area is sufficient for most of the species. This innovative analytical framework will guide the design of long-term monitoring projects suited to document and regularly update species distribution maps.

Aizpurua O., Paquet J.-Y., Brotons L. & Titeux N. (2014) Optimising long-term monitoring projects for species distribution modelling: how atlas data may help. Ecography, early view, doi: 10.1111/ecog.00749.

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New article: Dartford Warbler, unplanned fires and biodiversity conservation

Mediterranean landscapes are highly dynamic systems. Climate change is one of the most powerful driving forces of these dynamics and, in the Mediterranean basin, its severity has markedly increased in recent years. However, climate change impacts on biodiversity are often also indirect through changes in disturbance regimes  Fire is a critical factor in the Mediterranean and is likely to drive landscape change effects over large areas.

In this study, recently published in Journal of Ornithology, we ask the following questions: (1) how will climate change synergically with fire-conducted vegetation dynamics affect the distributional range of Dartford Warbler over the next 50 years?; and (2) can fire management offset distributional shifts caused by climate change and natural succession processes? Our group, in collaboration with Antoine Guisan’s lab (Department of Ecology and Evolution, University of Lausanne), ICO (Catalan Institute of Ornithology) and EBCC (European Bird Census Council), have assessed the potential changes in Dartford Warbler distribution between 2000 and 2050 under different fire management and climate change scenarios, and described landscape dynamics using a spatially-explicit fire-succession model that simulates fire impacts in the landscape and post-fire regeneration (MEDFIRE model).

The Dartford Warbler was recently evaluated on a global scale as Near Threatened in the IUCN Red List, since it is declining at a moderately rapid rate. Declines in the core populations in Spain are largely responsible for the estimated overall decline of the species due to habitat degradation and modification and climate changes. For this study, Dartford Warbler occurrence data were acquired at two different spatial scales from: (1) the Atlas of European Breeding Birds (EBCC) and (2) the Catalan Breeding Bird Atlas (CBBA). Habitat suitability was modelled using five widely-used modelling techniques in an ensemble forecasting framework (BIOMOD2).  

Our results thus highlight the need to take the spatial interaction among climate change, fire-mediated landscape dynamics and fire management policies in highly dynamic and fire-prone ecosystems into account to accurately predict habitat suitability changes of early-succession bird species in a context of land abandonment. Fire management programs must be integrated into conservation plans to effectively preserve sparsely forested and early-succession habitats and their associated species in the face of global change.

Regos A, D’Amen M, Herrando S, Guisan A, Brotons L (2015) Fire management, climate change and their interacting effects on birds in complex Mediterranean landscapes: dynamic distribution modelling of an early-successional species — the near-threatened Dartford Warbler (Sylvia undata). J Ornithol. doi: 10.1007/s10336-015-1174-9

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New article: Predictive modelling of fire occurrences from different fire spread patterns in Mediterranean landscapes

In a new work published recently in International Journal of Wildland Fire, we present a modelling exercise for predicting different fire spread patterns in Catalonia, NE Spain.

We introduce mathematically a novel classification of fires according to dominant fire spread pattern, an approach considered in operational fire-fighting, to help understand regional-scale spatial variability in fire regimes. Dominant fire spread patterns are usually linked to specific synoptic weather conditions, topography, or vegetation patterns, determining fire behavior and thus fire suppression opportunities. More deeply, we studied whether climate, topography and fuel variables allowed the prediction of occurrences from different fire spread patterns in Catalonia, NE Spain.

We used MaxEnt to model fire occurrences of wind-driven, topography-driven and convective fires for two different time periods (1989-1999 and 2000-2012). A cross-validation between the two decades modelled was conducted, and results were consistent in all types of fire. The variation partitioning analysis showed how convective fires were more related to forest fuel factors, while wind-driven fires were mostly predicted by unmanageable factors, as topography and wind. Topography-driven fires occurred over a broader range of environments where stronger fire spread determinants such as fuel loads or strong winds were not greatly inducing the occurrence of the other fire spread patterns.

The results presented offer new insights about potential approaches allowing the assessment of environmental change impacts on different types of fire spread patterns. Changes in land-use vegetation cover or changes in forest structure are just an example of the type of events that can differentially determine the occurrence of different kinds of spread patterns. Under a global change context where the future of fire regimes still being uncertain, these findings may have a strong impact on investigations into how fire regimes may be projected into the future under forecast global change as they suggest that future environmental changes may affect different fire spread patterns in an idiosyncratic manner.

Duane, A., Piqué, M., Castellnou, M., & Brotons, L. (2015). Predictive modelling of fire occurrences from different fire spread patterns in Mediterranean landscapes. International Journal of Wildland Fire, 24(3), 407-418.

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New article: Rewilding: a potential alternative approach to conservation in abandoned mountain areas?

Land-use change is a large component of global change and the effects on biodiversity and ecosystem services currently represent a major challenge for ecologists and conservationists. Several authors have recently suggested that REWILDING may be an appealing conservation response to farmland abandonment in areas of Europe where the social structure of farming communities has been eroded and low-intensity farming is no longer socially or economically viable. ECOLAND group, in collaboration with GRUMETS lab (CREAF and Autonomous University of Barcelona) and University of Santiago de Compostela (USC), have assessed the relative positive and negative effects of land abandonment on Gerês–Xurés Transboundary Biosphere Reserve (NW Iberian Peninsula) in order to quantify the potential conservation costs and benefits of a rewilding as a land-use management policy.

In a first study published in International Journal of Applied Earth Observation and Geoinformation, we aimed to determine if the abandonment of the rural areas was the main driver of landscape dynamics on this particular mountain area, or if other factors, such as wildfires and the land management were also directly affecting these spatio-temporal dynamics. For this purpose, we used earth observation data acquired from Landsat TM and ETM + satellite sensors, complemented by ancillary data and prior field knowledge, to evaluate the land use/land cover changes in our study region over a 10-year period (2000–2010). Our findings showed that rural exodus of the last century, differences in land management and fire suppression policies between Spain and Portugal and the different protection schemes could partly explain the different patterns of changes recorded in these covers.

In a second study, recently accepted in Regional Environmental Change, we investigated the effects of land abandonment processes on bird assemblages at both landscape and local scale. We combined medium-term data on avifauna distribution with information on temporal changes in land-use/land-cover extracted from satellite data. In light of our results, rewilding appears to have overall positive effects on biodiversity and should be considered by policy makers as alternative land-use strategy in marginal mountain areas, particularly if they have been historically affected by wildfires. Fire management aimed at favouring the creation of small burned areas in progressively closed landscapes derived from rewilding may be a complementary alternative to maintain open habitats in these areas.

Regos, A., Ninyerola, M., Moré, G., Pons, X., 2015. Linking land cover dynamics with driving forces in mountain landscape of the Northwestern Iberian Peninsula. Int. J. Appl. Earth Obs. Geoinf. 38, 1–14.

Regos, A., Domínguez, J., Gil-Tena, A., Brotons, L., Ninyerola, M., Pons, X., 2014. Rural abandoned landscapes and bird assemblages: winners and losers in the rewilding of a marginal mountain area (NW Spain). Reg. Environ. Chang.

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Tools for exploring habitat suitability for biodiversity under scenarios of rapid land use change.

A new article published in Agriculture, Ecosystems & Environment used scenario development based on changes in key socioeconomic drivers together with resource-based habitat suitability models to develop plausible visions of future pathways of agricultural land use and evaluate their potential consequences on conservation of target species. Analyses focused on three steppe bird species in a protected Natura 2000 area, located in the Iberian Peninsula. Our results showed that changes in land use composition under different scenarios can have important effects on habitat suitability, but that the size of those effects would vary depending on species-specific requirements and spatial distribution of land use changes.

Laura Cardador, Miquel De Cáceres, David Giralt, Gerard Bota, Núria Aquilué, Beatriz Arroyo, François Mougeot, Carlos Cantero-Martínez, Lourdes Viladomiu, Jordi Rosell, Fabián Casas, Alba Estrada, Jorge Álvaro-Fuentes, Lluís Brotons (2015).  Tools for exploring habitat suitability for steppe birds under land use change scenarios. Agriculture, Ecosystems & Environment 200: 119-125.

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New article: Woodland bird response to landscape connectivity in an agriculture-dominated landscape

In a new study published in the journal Community Ecology, Assu Gil-Tena and co-workers  have assessed the role of landscape connectivity in woodland bird species richness, abundance, and community similarity in north-east Brittany (north-west France). Over the last 30 years, ecological networks have been deployed to reduce global biodiversity loss by enhancing landscape connectivity. Bird species dwelling in woodland habitats that are embedded in agriculture-dominated landscapes are expected to be particularly sensitive to the loss of connectivity. In this study, an exhaustive woodland selection protocol was carried out to minimize the effects of woodland size on the response variables. Connectivity of the woodland and forest network in the study area was evaluated using graph-theory, accounting for matrix permeability, and a characteristic median natal dispersal distance at the community level based on the bird species pool recorded in the sampled woodlands. Information-theoretic model selection, controlling for woodland size in all the cases, depicted the response of woodland birds at the community level to the connectivity of agriculture-dominated landscapes. On average, the sampled woodlands (n = 25) contained 15.5 ± 2.4 bird species, with an abundance of 25.1 ± 3.9, and had highly similar bird communities (species composition and proportion); eight species represented 57% of total abundance and were present in at least 22 woodlands. The performance of models improved when using effective, rather than Euclidean, interpatch distances in the connectivity assessment. Landscape connectivity was only significantly related to similarity of proportional species composition. Large woodlands contained communities with more similar species proportions in an inhospitable agricultural landscape matrix than in a more permeable one. Woodland size was the most relevant factor determining species abundance, indicating that the bird population sizes are primarily proportional to the local habitat availability. Connectivity in relation to landscape matrix permeability did not seem to induce the flow of woodland-dependent bird species that are dominant in the community but rather of matrix-dwelling bird species that are less dependent on woodland patch area. In conclusion, both habitat conservation and restoration (i.e., amount and quality), in combination with permeable landscape structures (such as heterogeneous land cover mosaics), are advocated for community level conservation strategies.

Gil-Tena, A., Nabucet, J., Mony, C., Abadie, J., Saura, S., Butet, A., Burel, F., Ernoult, A. 2014. Woodland bird response to landscape connectivity in an agriculture-dominated landscape: a functional community approach. Community Ecology, 15(2): 256-268.

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New article: Species Distribution Models and Impact Factor Growth in Environmental Journals

In this work, we evaluate the impact of species distribution models (SDMs) on the current status of environmental and ecological journals by asking the question to which degree development of SDMs in the literature is related to recent changes in the impact factors of ecological journals. The results indicate a positive relationship between the number of SDM related articles published in a journal and its impact factor (IF) growth during the period 2000–09. The hypothesis evaluated states that research fronts are likely to attract research attention and potentially drive citation patterns, with journals concentrating papers related to the research front receiving more attention and benefiting from faster increases in their impact on the ecological literature.

However, the percentage of SDM related papers in a journal was strongly and positively associated with the percentage of papers on climate change and statistical issues. The results support the hypothesis that global change science has been critical in the development of SDMs and that interest in climate change research in particular, rather than the usage of SDM per se, appears as an important factor behind journal IF increases in ecology and environmental sciences. Finally, our results on SDM application in global change science support the view that scientific interest rather than methodological fashion appears to be the major driver of research attraction in the scientific literature.

Brotons L (2014) Species Distribution Models and Impact Factor Growth in Environmental Journals: Methodological Fashion or the Attraction of Global Change Science. PLoS ONE 9(11): e111996. doi:10.1371/journal.pone.0111996.

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New article: Reassessing global change research priorities in Mediterranean terrestrial ecosystems:

In a new article summarising findings from the CONSOLIDER-MONTES project, researchers involved in this project revisit the research priorities proposed in 1998 to unravel the challenges that global changes induce in Mediterranean systems.

Mediterranean terrestrial ecosystems serve as reference laboratories for the investigation of global change because of their transitional climate, the high spatiotemporal variability of their environmental conditions, a rich and unique biodiversity and a wide range of socio-economic conditions. As scientific development and environmental pressures increase, it is increasingly necessary to evaluate recent progress and to challenge research priorities in the face of global change.

A of research priorities is proposed: (1) to establish the role of the landscape mosaic on fire-spread; (2) to further research the combined effect of different drivers on pest expansion; (3) to address the interaction between drivers of global change and recent forest management practices; (4) to obtain more realistic information on the impacts of global change and ecosystem services; (5) to assess forest mortality events associated with climatic extremes; (6) to focus global change research on identifying and managing vulnerable areas; (7) to use the functional traits concept to study resilience after disturbance; (8) to study the relationship between genotypic and phenotypic diversity as a source of forest resilience; (9) to understand the balance between C storage and water resources; (10) to analyse the interplay between landscape-scale processes and biodiversity conservation; (11) to refine models by including interactions between drivers and socio-economic contexts; (12) to understand forest–atmosphere feedbacks; (13) to represent key mechanisms linking plant hydraulics with landscape hydrology.

Main conclusions (1) The interactive nature of different global change drivers remains poorly understood. (2) There is a critical need for the rapid development of regional- and global-scale models that are more tightly connected with large-scale experiments, data networks and management practice. (3) More attention should be directed to drought-related forest decline and the current relevance of historical land use.

Doblas-Miranda, E, J. Martínez-Vilalta, F. Lloret, A. Álvarez, A. Ávila, F. J. Bonet, L. Brotons, J. Castro, J. Curiel Yuste, M. Díaz, P. Ferrandis, E. García-Hurtado, J. M. Iriondo, T. F. Keenan, J. Latron, J. Llusià, L. Loepfe, M. Mayol, G.Moré, D.Moya, J. Peñuelas, X. Pons,
R. Poyatos, J. Sardans, O. Sus, V. R. Vallejo, J. Vayreda & J. Retana. 2014. Reassessing global change research priorities in mediterranean terrestrial ecosystems: how far have we come and where do we go from here? Glob. Ecol. & Biog, in press.

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New Article: Indicators of the impact of land use changes using large-scale bird surveys: Land abandonment in a Mediterranean region

In a new article recently published in Ecological Indicators, we developed a methodology to generate indicators capable to track the impact of land use changes in biodiversity using data from large scale monitoring projects. In particular we applied the proposed methodology to generate indicators to assess the impact that land abandonment has had in birds in Catalonia (NE Iberian Peninsula).

Generating sound indicators of biodiversity impact has been identified as a critical step towards our understanding of how global change components are affecting the environment across the globe. Land abandonment is recognized as a major component of global change in the Mediterranean basin, however, we lack adequate, quantitative, indicators of its impact on biodiversity. An appealing approach to develop biodiversity indicators is the use of large-scale bird monitoring projects, an important source of information that is already available in many countries. In this study we develop a method to quantify the impact of the two main processes associated with land abandonment in the Mediterranean region, namely the abandonment of farmland, which produces a shift from cultivated land to open natural habitats, and the encroachment by vegetation usually associated with reductions in livestock grazing and wood harvesting practices.

We used data from bird atlas and monitoring schemes in Catalonia (north-east Iberian Peninsula) to characterize species’ population response to these processes by means of detecting quantitative changes in relative abundances along a gradient ranging from habitats not affected by a given driving force to those that arise as a consequence of such force. We then generated multi-species indicators of the impact of these land use changes using these specific population responses to calibrate the relative contribution of each species in the composite index. The temporal patterns depicted by the two indicators in the period 2002–2011 show that vegetation encroachment did have a significant impact on bird communities, whereas any noticeable effect of farmland abandonment on bird populations was observed. The methodology proposed here could be employed to develop indicators capable to track biological impacts of land use change on an annual basis and inform decision-makers about the rate of increase or decrease on wildlife populations.

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Nou article: Indicadors de l’impacte dels canvis en els usos del sòl utilitzant el monitoratge dels ocells a gran escala: l’abandonament de la terra en una regió mediterrània

En un nou article recentment publicat a la revista Ecological Indicators, hem desenvolupat una metodologia que, a partir de les dades de projectes de monitoratge a gran escala, genera indicadors que poden avaluar l'impacte que els canvis soferts en els usos del sòl produeixen en la biodiversitat. En particular, hem aplicat aquesta metodologia per avaluar l'impacte que l'abandonament de terres agrícoles i forestals ha tingut en els ocells a Catalunya en la darrera dècada. Els resultats d’aquest treball quantifiquen l’impacte significatiu que ha tingut el creixement progressiu de la vegetació als sistemes naturals del nostre país. Per contra, aquest treball no mostra un efecte significatiu de l’abandonament de l’activitat pròpiament agrícola.

Herrando, S, Anton, M, Sardà-Palomera, F., Bota, G., Gregory, R.D., Brotons, L. (2014). Indicators of the impact of land use changes using large-scale birdsurveys: Land abandonment in a Mediterranean region. Ecological Indicators 45 (2014) 235–244. http://dx.doi.org/10.1016/j.ecolind.2014.04.011

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New article: Using Unplanned Fires to Help Suppressing Future Large Fires in Mediterranean Forests.

In a new article published in PLOS ONE, we assessed changes in fire suppression policies and their impact on fire regimes. Modulating fire suppression efforts in mild weather conditions is an appealing but hotly-debated strategy to use unplanned fires and associated fuel reduction to create opportunities for suppression of large fires in future adverse weather conditions. Using a spatially-explicit fire–succession model developed for Catalonia (Spain), we assessed this opportunistic policy by using two fire suppression strategies that reproduce how firefighters in extreme weather conditions exploit previous fire scars as firefighting opportunities.

We designed scenarios by combining different levels of fire suppression efficiency and climatic severity for a 50-year period (2000–2050). An opportunistic fire suppression policy induced large-scale changes in fire regimes and decreased the area burnt under extreme climate conditions, but only accounted for up to 18–22% of the area to be burnt in reference scenarios. The area suppressed in adverse years tended to increase in scenarios with increasing amounts of area burnt during years dominated by mild weather. Climate change had counterintuitive effects on opportunistic fire suppression strategies. Climate warming increased the incidence of large fires under uncontrolled conditions but also indirectly increased opportunities for enhanced fire suppression. Therefore, to shift fire suppression opportunities from adverse to mild years, we would require a disproportionately large amount of area burnt in mild years.

Despite the huge resources invested in fire suppression, the impact of wildfires has considerably increased across the Mediterranean region since the second half of the 20th century. We conclude that the strategic planning of fire suppression resources has the potential to become an important cost-effective fuel-reduction strategy at large spatial scale. We do however suggest that this strategy should probably be accompanied by other fuel-reduction treatments applied at broad scales if large-scale changes in fire regimes are to be achieved, especially in the wider context of climate change.

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Utilizant els focs no planificats per ajudar a suprimir grans focs futurs en boscos Mediterranis.

En un nou article publicat a PLOS ONE, hem avaluat com canvis en les polítiques de supressió del foc poden afectar el règim d’incendis en boscos Mediterranis. La modulació dels esforços de supressió del foc en períodes de climàtologia beningna es una estrategia debatuda per utilitzar focs no planificats  per reduir el fuel dels boscos i crear oportunitats  per suprimir futurs focs en condicions climàtiques adverses.

Regos A, Aquilué N, Retana J, De Cáceres M, Brotons L (2014) Using Unplanned Fires to Help Suppressing Future Large Fires in Mediterranean Forests. PLoS ONE 9(4): e94906. doi:10.1371/journal.pone.0094906

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New article: A Resource-Based Modelling Framework to Assess Habitat Suitability for Steppe Birds in Semiarid Mediterranean Agricultural Systems.

A new article has been published in PLoS ONE by ECOLAND and BACLAB members, with the collaboration of researchers from the IREC-CSIC, EEZA-CSIC, University of East Anglia and University of Lleida.

In this work included in the Steppeahead project included in the Proyecto 0 call from FGCSIC, the authors develop a resource-based model framework to estimate habitat suitability for target species, according to simple information on species’ key resource requirements (diet, foraging habitat and nesting site), and examine whether it can be used to link land-use and local species’ distribution.

The authors also compare the performance of the resource-based approach to that obtained through habitat-based models relating species’ occurrence and land-cover variables. Habitat suitability estimates generated by the resource-based models performed similarly (and better for one study species) than habitat based-models when predicting current species distribution. Moderate prediction success was achieved for three out of four species considered by resource-based models and for two of four by habitat-based models. Although, there is potential for improving the performance of resource-based models, they provide a structure for using available knowledge of the functional links between agricultural practices, provision of key resources and the response of organisms to predict potential effects of changing land-uses in a variety of context or the impacts of changes such as altered management practices that are not easily incorporated into habitat-based models.

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Nou article: Un model basat en la disponibilitat de recursos per estimar la qualitat de l’hàbitat d’aus estepàries en sistemes agrícoles mediterranis semiàrids.

Integrants dels grups ECOLAND i BACLAD del CTFC publiquen un nou article a la revista PLoS ONE, en col·laboració amb investigadors del IREC-CSIC, EEZA-CSIC, la Universitat de Lleida i la Universitat  de East Anglia.

En aquest treball, els autors desenvolupen un model basat en la disponibilitat de recursos per estimar la qualitat de l’hàbitat d’aus estepàries en sistemes agrícoles mediterranis i examinen si poden ser útils per predir la distribució local d’aquestes espècies. Els autors també comparen els resultats d’aquests models amb models correlatius d’hàbitat que relacionen directament els usos del sòl amb dades d’ocurrència de les espècies. Els models basats en la disponibilitat de recursos van predir la distribució local de les espècies de manera similar (i millor per un espècie) als models correlatius d’hàbitat.

Es van obtenir un èxit de predicció moderat per tres de les quatre espècies considerades amb els models de disponibilitat de recursos, i per dos de quatre amb els models correlatius d’hàbitat. Tot i que encara hi ha potencial per millorar els models basats en la disponibilitat de recursos, aquests ja proporcionen una estructura per utilitzar el coneixement disponible sobre els vincles funcionals entre les practiques agrícoles, la provisió de recursos i la resposta de les espècies per predir els efectes potencials dels canvis en els usos del sòl o en les practiques agrícoles en una gran varietat de contextos.

Laura Cardador, Miquel De Cáceres, Gerard Bota, David Giralt, Fabián Casas, Beatriz Arroyo, François Mougeot, Carlos Cantero-Martínez, Judit Moncunill, Simon J. Butler & Lluís Brotons. 2014. A Resource-Based Modelling Framework to Assess Habitat Suitability for Steppe Birds in Semiarid Mediterranean Agricultural Systems.  published 25 Mar 2014 | PLOS ONE.

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New article: Historical Ecology and Invasion Biology: Long-Term Distribution Changes of Introduced Freshwater Species

In this work, Miguel Clavero (Estación Biológica de Doñana, Sevilla) with support of Dani Villero (ECOLAND) show how analysis of historical datasets may have implications for present-day environmental management.

Based on Spanish historical written accounts from the sixteenth century to the present, they describe the long-term dynamics in the distributions of three freshwater species: tench (Tinca tinca), common carp (Cyprinus carpio), and white-clawed crayfish (Austropotamobius italicus). The results show the widespread, human-mediated expansion of the three species and support their introduced status, which has been controversial for tench and crayfish. The temporal patterns of spread of the three species differ dramatically. Although tench and crayfish expanded rapidly, carp spread mainly during the twentieth century, probably because of hydrologic alterations to Spanish streams. This prolonged time lag in the expansion of an introduced species calls for precaution when judging species invasiveness. Austropotamobius italicus is the focus of several conservation actions in Spain, a strategy that should be questioned in the view of the crayfish's probable introduced status.

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Ecología històrica i biologia de les invasions

En aquest treball, Miguel Clavero (Estación Biológica de Doñana, Sevilla) amb el recolzament de Dani Villero (ECOLAND) mostren com els anàlisis de dades històriques poden tenir implicacions en les estratègies de conservació portades a terme en l’actualitat.

Basant-se en dades històriques publicades a Espanya des de mitjans del S.XVI fins a l’actualitat, han descrit la dinàmica de la distribució a llarg termini de 3 espècies d’aigües continentals: la tenca (Tinca tinca), la carpa (Cyprinus carpio) i el cranc de riu (Austropotamobius italicus). Els resultats mostren com en el passat l’àmplia expansió de les tres espècies va ser facilitada per l’home, donant suport al seu estatus d’espècies introduïdes, fet molt controvertit en els casos de la tenca i el crac de riu. Els patrons de dispersió de les tres espècies son molt diferents. Encara que la tenca i el cranc de riu es van expandir ràpidament, la carpa es va expandir principalment al llarg del S.XX, probablement a causa de alteracions hidrològiques dels rius espanyols. Un Aquest lapse temporal tant dilatat per a l’expansió d’una espècie introduïda suggereix que cal aplicar el principi de precaució alhora de jutjar la capacitat invasiva de les espècies. El cranc de riu (Austropotamobius italicus) es objecte de nombroses accions de conservació a Espanya, una estratègia de conservació que cal posar en qüestió a la llum del seu probable nou estatus d’espècie introduïda.

Clavero, M & Villero, D. 2014. Historical ecology and invasion biology: long-term distribution changes of introduced freshwater species. Bioscience, 64:145-153.

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New article: Incorporating spatial constraints in different periods of the annual cycle improves species distribution model performance for a highly mobile bird species

Incorporating spatial constraints in different periods of the annual cycle improves species distribution model performance for a highly mobile bird species

A new article published in Diversity & Distributions and lead by Laura Cardador from the ECOLAND group, examines the role that pure distance effects and niche-based environmental responses can play in limiting the large-scale distribution of highly mobile species.

Using an expanding raptor species, the marsh harrier Circus aeruginosus, in Spain as a model, the article provides evidence that distribution of highly mobile species can be spatially constrained beyond environmental variables and that the effect of spatial constraints can vary in different periods of the annual cycle. Contrary to the equilibrium postulate, results found in this study support the prediction that environmental specializations do not necessarily result in complete habitat matching due to dispersal limitations. Thus, ignoring spatial constraints in species distribution models can lead to misunderstandings of the ecological mechanisms that explain species range limits. The sutdy was supported by the project Steppeahead, funded by CSIC, FGSIC and Banco Santander, during part of this study.

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La incorporació de constriccions espacials en diferents períodes del cicle anual millora la precisió dels models de distribució d’una espècie altament mòbil 

Un nou article publicat a la revista Diversity & Distributions i liderat per Laura Cardador de l’equip ECOLAND, analitza el paper que juguen les variables ambientals i les constriccions espacials en limitar la distribució d’espècies altament mòbils. Usant com a model, la distribució de l’arpella vulgar Circus aeruginosus a Espanya, l’article mostra que els patrons de distribució d’espècies altament mòbils poden no ajustar-se completament als requeriments climàtics i d’hàbitat d’aquestes espècies degut a l’existència de limitacions espacials, com per exemple les resultants de limitacions dispersives. Aquestes constriccions poden diferir, a més, entre diferents períodes del cicle anual. En aquest sentit, no tenir en compte les constriccions espacials en el models de distribució d’espècies pot portar a males interpretacions dels mecanismes ecològics que expliquen el rang de distribució d’aquestes.  La Laura Cardador forma part de l’equip del projecte Steppeahead, finançat pel CSIC, FGSIC i Banc Santander.

Cardador, L., Sardà-Palomera, F., Carrete, M. & Mañosa, S. (2013) Different periods of the annual cycle improves species distribution model performance for a highly mobile bird species. Diversity & Distributions.

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New article: Predicting species distributions for conservation decisions

The new article published in Ecology Letters aims at facilitating the use of Species distribution models (SDMs) in decision making and conservation. This article has been magnificently led by Antoine Guisan (Univ. Genève) and is derived from a series of workshops hosted by CEED on this topic and held in Melbourne and Brisbane (Australia) during 2011 and 2012.

SDMs are increasingly proposed to support conservation decision making. However, evidence of SDMs supporting solutions for on-ground conservation problems is still scarce in the scientific literature. Here, we show that successful examples exist but are still largely hidden in the grey literature, and thus less accessible for analysis and learning. Furthermore, the decision framework within which SDMs are used is rarely made explicit.

Using case studies from biological invasions, identification of critical habitats, reserve selection and translocation of endangered species, we propose that SDMs may be tailored to suit a range of decision-making contexts when used within a structured and transparent decision-making process.

To construct appropriate SDMs to more effectively guide conservation actions, modellers need to better understand the decision process, and decision makers need to provide feedback to modellers regarding the actual use of SDMs to support conservation decisions. This could be facilitated by individuals or institutions playing the role of ‘translators’ between modellers and decision makers.

We encourage species distribution modellers to get involved in real decision-making processes that will benefit from their technical input; this strategy has the potential to better bridge theory and practice, and contribute to improve both scientific knowledge and conservation outcomes.

Guisan et al. 2013. Predicting species distributions for conservation decisions. Ecology Letters in press.

Ecoland participation in the workshops has been provided by the Catalan Government (BE grants, and CARTOBIO) and the SCALES project.

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Modelling the distribution of the European wild rabbit in fragmented environments

Ecoland members have investigated the factor affecting the occurrence of European wild rabbit in fragmented environments in a mountainous area of northwestern Spain (Gerês-Xurés Biosphere Reserve). The study has been led by Luis Tapia and conducted in collaboration with Jesús Domínguez and Maria Vidal from University of Santiago de Compostela. 

Field survey was carried out by sampling the presence/absence of pellets in 237 plots (100 x 100 m) selected at random below an altitude of 800 m. For modeling purposes, we considered eight predictors related to vegetation, topography, human influence and heterogeneity. All predictors were obtained from Landsat-derived maps by using a Neuronal Artificial Neural Networks algorithm, and a Global Digital Elevation Model (GDEM). Generalized linear model were used to describe the occurrence of the European wild rabbit.

The information on habitat requirements of European wild rabbit in the area provides a good framework for determining the habitat requirements of this keystone species in mountainous ecosystems in northwestern Iberian Peninsula and confirms that digital data-based models can solve many of the problems associated with field data in wildlife modelling.

TAPIA, L; DOMÍNGUEZ, J.; REGOS, A. and VIDAL, M. (2013). Using remote sensing data to model European wild rabbit (Oryctolagus cuniculus) occurrence in a highly fragmented landscape in northwestern Spain. Acta Theriologica, doi: 10.1007/s13364-013-0169-2.

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Conservation planning in a dynamic world: Biodiversity and fire in the Mediterranean region

In response to the processes threatening
biodiversity such as habitat loss, effective selection of priority conservation areas is required to ensure long term persistence of key species. However, reserve selection methods usually ignore the drivers of future habitat changes, thus compromising the effectiveness of conservation.

In a new article published in Landscape Ecology and led by Sara Vallecillo, we formulated an approach to explicitly quantify the impact of fire on the selection of priority conservation areas, considering such disturbance as a driver of land-cover changes. This work emphasizes the need to consider the opposing potential impacts of wildfires on species for an effective conservation planning.This is the first study originated from our collaboration with Australian researchers from the Griffith University, Virgilio Hermoso, and the Center of Excellence for Environmental Decisions, CEED lead by Hugh Possingham).

The estimated fire impact was integrated as a constraint in the reserve selection process to tackle the likely threats or opportunities that fire might cause to the targeted species depending on their habitat requirements. In this way, we selected conservation areas in a fire-prone Mediterranean region for two bird assemblages: forest and open-habitat species. Differences in conservation areas selected before and after integrating the impact of fire in the reserve selection process were assessed. Integration of fire impact for forest species moved preferences towards areas that were less prone to burn.However, a larger area was required to achieve the same conservation goals.

Conversely, integration of fire impacts for open-habitat species shifted preferences towards conservation areas in locations where the persistence of their required habitat is more likely (i.e. shrublands). In other words, we prioritized the conservation of not only the current distribution of open-habitat birds, but also the disturbance process (i.e. fire) that favours their preferred habitat and distributions in the long term.

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Planificació de la conservació en un món dinàmic: biodiversitat i foc a la regió Mediterrània.

En un nou article publiscat a la revista Landscape Ecology i liderat per  Sara Vallecillo, es formula una nova aproximació per quantificar de manera explíctia l’impacte del foc en la selecció d’àreas amb prioritat de conservació en paisatges dinàmics afectat pels incendis. Aquest és el primer treball originat a partir de la nostra colaboració amb investigadors Australians de la Griffith University, Virgilio Hermoso, i del Center of Excellence for Environmental Decisions, CEED lead by Hugh Possingham).

Vallecillo, S., Hermoso, V., Possingham, H. & Brotons, L. 2013. Conservation planning in a fire-prone Mediterranean region: threats and opportunities for bird species. Landscape Ecology in press.

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New article: The combined effects of land-use and novel fire regimes on bird distributions in the Mediterranean

In a new article published in Journal of Biogeography co-authored with M.J. Fortin, members of the ECOLAND group have investigated whether fire regimes resulting from the combination of climate change, fire-fighting policy and the spatial legacy of historical land use may affect the distribution of species in Mediterranean landscapes.

The study was conducted using Catalonia as study area and 64 bird species with different habitat preferences as target species. The MEDFIRE fire-succession model was used to stochastically simulate land-cover changes between 2000 and 2050 under different scenarios and species distribution models were used to predict habitat suitability and occupancy dynamics under either no dispersal or full dispersal assumptions. Under many simulated scenarios, the succession from shrubland to forest dominated over the creation of new low-vegetation areas derived from wildfires. Consequently, open-habitat specialists were the group most affected by losses of suitable habitat. Moreover, fire regimes obtained under scenarios including high fire suppression efficiency resulted in a larger number of bird species experiencing reductions in their distribution area.

These two simulation results stress that anthropogenic factors, such as historical land-use change and fire suppression, can drive regional distribution dynamics in directions opposite to those expected from climatic trends. This raises the question of what drivers and interactions should be given priority in the prediction of bio- diversity responses to global change at the regional scale.

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Els efectes combinats dels canvis d’ús i el foc sobre els canvis de distribució d’ocells

En un article publicat recentment a la revista Journal of Biogeography, i en co-autoria amb M.J. Fortin, tres membres del grup ECOLAND han investigat fins a quin punt el règim d’incendis resultant de la interacció entre el canvi climàtic, les polítiques d’extinció i el llegat espaial de usos històrics del sòl afectarà la distribució d’espècies en paisatges Mediterranis.

L’estudi ha estat realitzat prenent Catalunya com a àrea d’estudi i modelitzant la distribució de 64 espècies d’ocells amb diferents preferències d’hàbitat. El model de simulació de paisatge MEDFIRE ha estat utilitzat per a simular estocàsticament els canvis de cobertes en el paisatge entre 2000 i 2050, sota diferents escenaris sorgits de la combinació de tractaments de canvi climàtic i polítiques d’extinció. Models de distribució d’espècies foren utilitzats per a predir canvis en la adequació de l’hàbitat o canvis en la dinàmica de la ocupació assumint una capacitat de dispersió nul·la o il·limitada.

Sota la majoria d’escenaris simulats, la successió de matollar a bosc predominà per sobre de la creació de nous hàbitats amb vegetació baixa derivats de l’acció del foc. En conseqüència, els ocells especialistes d’espais oberts foren els més afectats per la pèrdua d’habitat. Consequently, open-habitat specialists were the group most affected by losses of suitable habitat. A més, els règims d’incendis obtinguts en escenaris que incloïen una major eficiència de suppressió conduïren a un major nombre d’espècies on els canvis d’hàbitat reduïren la seva àrea de distribució. Aquests resultats de simulacions posen èmfasi en el fet que els factors antropogènics com els canvis d’usos o la política d’extinció d’incendis poden tenir una importància més gran que els canvis climàtics com a determinants dels canvis en la distribució de les espècies a escales regionals. Aquest fet posa sobre la taula la qüestió de quins factors i interaccions cal prioritzar en la predicció de la resposta de la biodiversitat al canvi global a escala regional.

Cáceres M, Brotons, L, Aquilué, N, Fortin, MJ (early view) The combined effects of land use legacies and novel fire regimes on bird distributions in the Mediterranean. Journal of Biogeography (http://dx.doi.org/10.1111/jbi.12111).

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New article: Effects of the non-native amphibian species Discoglossus pictus on the recipient amphibian community: niche overlap, competition and community organization

A new article led by Alex Richter-Boix (Uppsala University, Sweden) and Núria Garriga (Barcelona University, Spain), with support of Dani Villero from ECOLAND, examines the effects of the non-native Discoglossus pictus (Amphibia: Discoglossidae) on amphibian assemblages from the north-east of the Iberian Peninsula, suggesting that competition between native and non-native species can cause recipient communities to become less structured, and thus, more vulnerable to other impacts threatening amphibian populations at the Mediterranean basin.

Niche overlap analyses between species in regions with and without D. pictus revealed differences in the co-occurrence patterns of species, with structured communities in the non-invaded area and random non-structured communities in the invaded area. One possible cause of the alteration of species co-occurrence patterns in the recipient community on a regional scale are competitive interactions in larval communities at breeding sites. Laboratory assessments on competition consequences with D. pictus tadpoles supported that hypothesis, showing significant negative interactions with the two most commonly overlapped species, Bufo calamita and Pelodytes punctatus, which reduced survival, body mass, activity and consumption rate, and delayed metamorphosis.

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Un nou treball, liderat per Alex Richter-Boix (Uppsala University, Sweden) i Núria Garriga (Universitat de Barcelona), i amb el suport de Dani Villero d’ECOLAND, examina els efectes de l’espècie introduïda Discoglossus pictus (Amphibia: Discoglossidae) en les comunitats d’amfibis del nord-est de la Península Ibèrica, suggerint que la competència amb altres espècies pot provocar la desestructuració de les comunitats autòctones d’amfibis i, per tant, més vulnerables als impactes que amenacen les poblacions d’amfibis a la conca Mediterrània.

L’anàlisi de solapament del nínxol entre espècies en regions amb o sense D. pictus va posar de manifest diferències en els patrons de co-occurrència de les espècies, amb comunitats d’amfibis desestructurades en àrees envaïdes per D. pictus i comunitats ben estructurades en àrees on l’espècie encara no ha arribat. Una possible causa de l’alteració d’aquests patrons de co-occurrència en les comunitats receptores a escala regional és la competència en les comunitats de larves en els llocs de reproducció. Els assajos de laboratori per avaluar les conseqüències de la competència amb larves de D. pictus van donar suport a aquesta hipòtesi, mostrant interaccions negatives significatives amb les espècies que mostren major solapament de nínxol, Bufo calamita i Pelodytes punctatus, amb la reducció de la supervivència, massa corporal, activitat i taxes de consum, i el retard de la metamorfosi.

Richter-Boix, A., Garriga, N., Montori, A., Franch, M., San Sebastián, O., Villero, D. & Llorente, G.A. (2013).Effects of the non-native amphibian species Discoglossus pictus on the recipient amphibian community: niche overlap, competition and community organization. Biol. Invasions (2013) 15:799–815 DOI 10.1007/s10530-012-0328-4.

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New article: TEASIng apart alien species risk assessments

Members of the ECOLAND group have participated in a new article in the journal Ecology Letters in which a rigorous, conceptual risk assessment framework to assess risks posed by invasive species has been proposed.

The European Science Foundation (ESF) and the Agency for Management of University and Research Grants (AGAUR) of the Government of Catalonia jointly funded a workshop on methods and applications of risk assessment analysis in managing biological invasions. The workshop was hosted at the University of Girona during April 2011. The meeting brought together 21 researchers from around the world with expertise in various aspects of invasion ecology and an interest in contributing to the development of a more robust framework for and standard protocols for effective risk assessment.

Much research is focussing on developing risk assessment protocols that identify species that pose a high risk of becoming established, spreading and having negative impacts. Formal risk analysis for invasive species aims to provide systematic and comprehensive methodologies for evaluating risks and uncertainties associated with the introduction/spread of organisms, based on the magnitude of possible adverse consequences and the likelihood of occurrence of these consequences. In many countries, legislation relating to invasive species calls for the implementation of formal risk assessment tools to reduce further invasions.

A sub-group of workshop participants lead by Prof. Brian Leung (McGill University, Montreal, Canada) was tasked with producing a rigorous conceptual risk assessment framework by reviewing more than 300 published risk assessment studies. The paper, published in the journal Ecology Letters, defined risk in relation to each of the major stages in the invasion process: Transport, Establishment, Abundance, Spread, and also with regard to Impact — the “TEASI” framework. TEASI components, subcomponents, dependencies, and relationships among these elements are discussed, and combined mathematically into a quantitative RA structure.

By mapping each risk assessment in the conceptual TEASI framework, the authors illustrate that the qualitative/semi-quantitative scoring methods are special cases of quantitative models. This framework thus provides the skeleton structure and serves as a starting point for advances in risk modelling. Importantly, the aim in promoting such an integrative approach was not to suggest that all elements need to be estimated to yield a useful risk assessment, but rather to identify opportunities for improvement, by explicitly demonstrating how different processes in invasion are linked. Most implementations of risk analysis do not cover all elements of the invasion process and the new framework provides guidance on which elements should be included in risk assessments and how they should be combine

Leung, B., Roura-Pascual, N., Bacher, S., Heikkilä, J., Brotons, L., Burgman, M.A., Dehnen-Schmutz, C. Essl, F., Hulme, P.E., Richardson, D. M., Sol, D. & Vilà, M. (2012) TEASIng apart alien species risk assessments: a framework for best practices. Ecology Letters, in press.

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