Julia Gómez-Catasús

El Congreso Internacional sobre Aves Esteparias del Paleártico (International Conference on Palearctic Steppe Birds –ICPSB 2025), celebrado en Ciudad Real, reunió a especialistas de todo el Paleártico para compartir y sintetizar el conocimiento más reciente sobre la ecología y conservación de las aves esteparias en un contexto de declive acelerado. Este artículo presenta una síntesis de los principales avances científicos y mensajes clave del congreso, abarcando temas como tendencias poblacionales, estrategias vitales, movimientos y migración, cambios de hábitat, impactos de infraestructuras, cambio climático y marcos de política ambiental. Son destacables los progresos metodológicos en seguimiento poblacional, el uso de nuevas tecnologías y la integración de enfoques demográficos y espaciales para evaluar amenazas y medidas de gestión que se discutieron en el congreso. El congreso puso de manifiesto que la pérdida y degradación del hábitat, la intensificación agraria, la expansión de infraestructuras y el cambio climático actúan de forma conjunta y son causa del declive de las poblaciones de aves esteparias, generando cuellos de botella demográficos difíciles de revertir con medidas aisladas. Frente a ello, ICPSB 2025 subrayó la necesidad de estrategias integradas, multiescalares y basadas en la evidencia, así como de una mayor coordinación internacional y una conexión más efectiva entre ciencia, gestión y políticas públicas. El artículo concluye identificando prioridades de acción y líneas de trabajo futuras para mejorar la eficacia de la conservación de las aves esteparias en el Paleártico.—Bravo, C., Traba, J. y Gómez-Catasús, J. (2026). Síntesis científica del congreso internacional sobre aves esteparias del paleártico – Ciudad Real 2025: Avances y conclusiones sobre la conservación de las aves esteparias. Ardeola, 73: 3-14.

Scenario analysis allows assessing how complex socio‐ecological systems might respond to different policy pathways. We used an expert‐based participatory approach to explore how four different European socio‐ecological scenarios could impact (1) the implementation of the Kunming–Montreal Global Biodiversity Framework (KM‐GBF) and (2) the achievement of priority conservation actions for safeguarding European steppe ecosystems. KM‐GBF targets were expected to be met only under the scenario with increased commitment for sustainable development goals and global cooperation, but hardly achievable under the most environment‐adverse and resource‐demanding scenarios. Integrating different views from these scenarios, we identified six overarching recommendations for the conservation of European steppe ecosystems, including improving public awareness, empowering local communities, and promoting the engagement of private companies into conservation planning. Our approach identifies how socioeconomic drivers influence the success of the KM‐GBF and the conservation of European steppes, providing a range of general conservation actions structured and prioritized to be effective under a wide range of likely future developments.

En el presente estudio se investiga la presencia, identidad y prevalencia de infestación de garrapatas en distintas especies de aves esteparias en el centro de España, además del potencial papel que puede tener el pastoreo sobre ello. Además, se determina, a través de técnicas moleculares, la presencia de patógenos transmitidos por garrapatas en las distintas especies de aves y la presencia de malaria aviar en garrapatas. Por otro lado, se analiza la variación de prevalencia, tanto de infestación por garrapatas, como de malaria aviar, en función de la especie de ave y de la carga ganadera presente en la zona de estudio. La prevalencia de infestación por garrapatas varió entre el 1.7% en la collalba rubia (Oenanthe hispanica) y el 46.3% en la alondra ricotí (Chersophilus duponti), siendo significativamente más alta en la alondra ricotí. La presencia de garrapatas con malaria aviar se detectó en dos de las especies analizadas. El porcentaje de garrapatas en las que se detectó presencia de malaria aviar fue del 100% en el caso de la collalba rubia (dos garrapatas analizadas), y del 21.6% en el caso de la alondra ricotí (de las 409 garrapatas analizadas). La presencia de garrapatas y la prevalencia de malaria no se relacionaron significativamente con la intensidad de uso ganadero. Nuestros resultados proporcionan información nueva y relevante sobre la probabilidad de infestación por garrapatas en aves esteparias y su potencial papel como vector de enfermedades infecciosas.

In recent decades, Europe has seen a notable decrease in extensive grazing by domestic livestock; endangering semi‐natural open habitats; and impacting soil, vegetation, arthropods and insectivores. Despite the known ecological consequences of grazing decline, little research has explored the role of sheep dung in influencing plant cover, arthropod biomass and higher trophic levels, such as insectivorous birds. To address this gap, a 3‐year study (2017–2019) was conducted in a Mediterranean shrub‐steppe in central Spain. Two 10‐hectare non‐grazed experimental plots received different doses of sheep dung, while a grazed area served as a reference. Vegetation structure was assessed annually, arthropods were sampled six times per year and the breeding space use of a threatened insectivorous bird was estimated annually. While dung input did not affect vegetation structure, it had short‐term positive effects on some arthropods, particularly epigeous and coprophagous species. Additionally, the insectivorous bird increased its use of space in response to dung application, likely due to the rise in arthropod biomass, a critical food resource. In areas where sheep grazing is declining, sheep dung inputs may serve as an effective short‐term strategy to increase the biomass of specific arthropod groups, indirectly benefiting their predators. Further research is needed to assess long‐term effects on arthropod communities and a wider range of insectivorous species, aiding conservation efforts in areas facing low grazing pressures.

A species’ diet is highly dependent on the availability of food resources in space and time, as well as on intrinsic factors such as sex or age. Accurate assessments of variations in the diet composition of bird populations across spatial scales, seasons and demographic groups are essential not only for understanding the basic ecology of species, but also for the conservation of endangered ones. However, our current knowledge about how birds’ diet change according to spatio-temporal variations or intrinsic factors is very limited. Here, we used a multi-marker metabarcoding approach to characterize the diet of a declining shrub-steppe passerine, the Dupont’s Lark (Chersophilus duponti), throughout a large part of its global distribution range. We also investigated spatial, phenological and sexual variations in its diet. Using markers from two genomic regions (18S and COI), we analyzed fecal samples from 303 adult Dupont’s larks from Morocco and Spain during the breeding and non-breeding seasons. Overall, arthropods from the orders Coleoptera, Lepidoptera, Julida and Orthoptera were the main prey consumed by Dupont’s Larks. We found that Dupont’s Lark diet varied spatially, as well as temporally, reflecting dietary plasticity in response to changes in prey availability across landscapes and the species’ phenological periods. High dietary overlap and no differences between sexes were observed, suggesting similar foraging behavior and nutritional requirements in both sexes. This is the first study providing detailed information on Dupont’s Lark food ecology over much of its distribution, which is fundamental for the management and conservation of this declining steppe species.

Mediterranean natural steppes have drastically changed in the last few decades due to land abandonment, agricultural intensification, and land use change, such as tree afforestations. These factors have caused large declines in steppe bird populations, one of the most threatened bird groups in Europe. Conservation of steppe birds may require active land restoration actions, but little is known about how to manage steppe habitats and their impact on steppe birds’ populations. LIFE Ricotí project carried out actions to restore steppe habitat by removing 50 ha of pine afforestations and tree-thinning in 250 ha, mainly holm oaks (Quercus ilex). These actions aimed to conserve the Dupont’s lark (Chersophilus duponti), a threatened insectivorous and strict steppe bird with dramatic population and habitat reduction in the last years. We tested the efficiency of these restoration actions by monitoring arthropod biomass – used as a surrogate of habitat quality for insectivorous birds – and Dupont’s lark abundance, both in reference and restored areas following a BACI design over four years (including three after restoration). Biomass of most arthropod groups did not vary between restored and reference areas, although restoration significantly increased the biomass of epigeous arthropods in the case of pine removal, and specifically Coleoptera. In the case of holm oak tree-thinning, arthropod biomass was barely affected by restoration. Dupont’s lark male territories significantly increased (from 15 to 27) in restored areas, especially in the two holm oak thinning areas, while they decreased in the reference area (from 145 to 91). Our results show a significant increase of Dupont’s lark abundance in restored areas, likely owing to an improvement in habitat suitability, since this species avoids forested areas. Our results show a successful restoration of steppe habitats and improvement of the conservation status of a threatened species, such as Dupont’s lark, while not affecting or even increasing arthropods biomass.

Solar photovoltaic (PV) has become the second renewable energy source, giving rise to potential conflicts with biodiversity conservation. However, the information available about the impacts and mitigation measures of solar PV energy is scarce and scattered, and a rigorous and comprehensive review on the topic is lacking. Here, we review the state of knowledge on its impacts and mitigation measures and identify main knowledge gaps. For that, we reviewed more than 2000 articles, out of which only 180 assessed the impacts of solar PV ( N = 138) and/or propose mitigation measures (65). Even though Asia and Europe head the list of regions with the highest PV installed capacity (59% and 22%, respectively), a large portion of the existing knowledge is drawn from North American environmental contexts (48% of the studies), specifically from deserts (41%). Impacts were addressed on plants (26%), arthropods (14%), birds (10%), microorganisms (10%), reptiles (7%), mammals (4%), and bats (1%), but also on abiotic factors (e.g., humidity and temperature; 20%) and ecosystem services (3%). Most studies addressed the impact of PV on habitat alteration at landscape (33%) and microhabitat scale (20%), and on microclimate at microhabitat scale (17%), but other topics have been scarcely addressed (e.g., impact on microclimate at landscape scale or the potential of agrivoltaic systems). Lastly, 53% of the studies employed a single PV facility, and preconstruction situations were rarely reported (8%). There is a strong environmental context bias in the current understanding of PV impacts, which might not be extrapolable to other environmental situations like farmlands, where most of the solar PV capacity is being installed. Moreover, standardized and robust sampling designs are lacking to address cumulative, long‐term, and long‐scale impacts and produce comparable findings across contexts. Given the lack of empirical evidence and the irrepressible development of PV energy, it is advisable to apply an iterative monitoring and adaptive process to guarantee a safe energy transition. This review may provide useful guidance on prioritizing research efforts for a smooth shift to renewable energy.

A species’ diet is highly dependent on the availability of food resources in space and time, as well as on intrinsic factors such as sex or age. Accurate assessments of variations in the diet composition of bird populations across spatial scales, seasons and demographic groups are essential not only for understanding the basic ecology of species, but also for the conservation of endangered ones. However, our current knowledge about how birds’ diet change according to spatio-temporal variations or intrinsic factors is very limited. Here, we used a multi-marker metabarcoding approach to characterize the diet of a declining shrub-steppe passerine, the Dupont’s Lark ( Chersophilus duponti ), throughout a large part of its global distribution range. We also investigated spatial, phenological and sexual variations in its diet. Using markers from two genomic regions (18S and COI), we analyzed fecal samples from 303 adult Dupont’s larks from Morocco and Spain during the breeding and non-breeding seasons. Overall, arthropods from the orders Coleoptera, Lepidoptera, Julida and Orthoptera were the main prey consumed by Dupont’s Larks. We found that Dupont’s Lark diet varied spatially, as well as temporally, reflecting dietary plasticity in response to changes in prey availability across landscapes and the species’ phenological periods. High dietary overlap and no differences between sexes were observed, suggesting similar foraging behavior and nutritional requirements in both sexes. This is the first study providing detailed information on Dupont’s Lark food ecology over much of its distribution, which is fundamental for the management and conservation of this declining steppe species.

Territorial defence depends on highly interrelated factors such as food abundance and conspecific density. We used Dupont's Lark Chersophilus duponti as a model species to evaluate the response of a territorial bird to a foreign male playback, examining how conspecific density, habitat quality and male body condition impact responses. The study was conducted in central Spain with variable male density. Response (yes/no), latency time, distance to the playback speaker, and the number of songs and other vocalizations were monitored for 5 min. Habitat quality was estimated using BlueNDVI vegetation index extracted from high‐resolution drone imagery, which is a proxy for arthropod prey biomass. Conspecific density (Kernel Density Estimator) and male body condition were calculated to assess their effect on response and intensity. We applied generalized linear mixed models (GLMMs) to determine which factors predicted the response and its intensity. There was a greater response probability in areas with a higher density of conspecifics and in areas of poorer habitat quality (i.e. lower BlueNDVI values). In contrast, latency time was longer in areas with lower conspecific density. Intrasexual communication (singing and calling rates) increased with habitat quality. Intraspecific communication (other vocalizations) increased in poorer quality habitats and at a higher density of conspecifics. Body condition was not related to any variables. Our results suggest that male density, sometimes used as an indicator of an area being well conserved for the species, may reflect areas of poorer habitat quality occupied by unpaired floater males, whereas paired territorial males would occupy and defend higher quality areas, leading to lower density.