Tendencias poblacionales recientes de la avutarda hubara en las Islas Canarias: análisis metodológico y estado de conservación

El establecimiento del estatus de conservación demanda la existencia de datos rigurosos y fiables acerca de los efectivos y las tendencias poblacionales, especialmente si se han de aplicar en islas en donde las especies tienen poblaciones pequeñas. Este trabajo analiza la valía de los resultados previos para la hubara utilizando el método de transectos lineales adyacentes separados 200 m, como puntos de partida adecuados para establecer tendencias poblacionales robustas en las 30 localidades principales de las islas de Lanzarote y Fuerteventura. Para ello se efectuaron censos en las mismas fechas (noviembre–diciembre 2011) y localidades estimando la probabilidad de detección. Este método de censo, que estima el máximo número de hubaras diferentes detectadas, proporciona valores de densidad muy poco subestimados (detección del 95,2% de las aves), por lo que las estimas previas de abundancia pueden ser consideradas como fiables (i.e., probable subestima media de un 5%). No obstante, los intervalos de confianza de las estimas de hubaras en las zonas prospectadas mediante un solo censo fueron enormes. Por tanto, con un solo censo por localidad y año no es posible obtener estimas precisas con un escaso margen de variabilidad en torno al valor medio. Esto plantea un problema considerable a la hora de obtener evidencias sólidas acerca de la certeza de los aumentos–disminuciones de los efectivos poblacionales al comparar fechas o zonas diferentes. La avutarda hubara ha disminuido significativamente su densidad de 2004/2006 a 2011 en ocho zonas de Fuerteventura (Vega Vieja, Los Alares–Pocetas, Matas Blancas, Lorenzo–Diviso, Corralejo, Lajares y Fimapaire) y en dos de Lanzarote (Argana y La Santa). Por el contrario, la densidad de la hubara ha aumentado significativamente en tres localidades de Lanzarote (Zonzamas, Guatiza y llano de Las Maretas). Globalmente, las estimas medias por isla no difirieron significativamente entre 2004/2006 y 2011 en Fuerteventura (leve disminución del 29% en 2011), pero sí en Lanzarote (aumento del 60% en 2011). El cambio de densidad entre los dos periodos de estudio tendió al incremento en 2011 en las localidades más alejadas de la carretera asfaltada más cercana, y tendió a la disminución en 2011 en las zonas con suelo predominantemente arenoso.Determining conservation status requires rigorous and reliable data about population sizes and trends, especially if they have to be applied to islands where the species have small populations. The Canary bustard houbara (Chlamydotis undulata fuertaventurae) is catalogued as ‘in danger’ by the Red Book of the Birds of Spain. This work analyzes the value of previously published information on the species using the method of adjacent linear transects separated by 200 m, as a baseline for establishing robust population trends in 30 important areas (ranging from 1.3 to 12.8 km2) for the houbara in the islands of Lanzarote and Fuerteventura (Canary Islands). Censuses were repeated on the same dates (from November to December) and localities as those carried out in 1994, 2004 and 2006. The detection probability of the houbara was estimated by means of distance sampling, being 0.42 up to 250 m from the observer, and 0.82 in the main census belt of 100 m on either side of the line transect. The method of adjacent linear transects —counting the maximum number of hubaras detected— provides accurate figures of population densities (detection of 95.2% of the birds). The previous estimations of houbara densities can therefore be considered highly trustworthy, with a probable average underestimation of only 5 %. Nevertheless, the confidence intervals of density estimations using only one census were very large. Therefore, with only one census per sampling area and year it is not possible to obtain precise estimates of houbara densities with small variation around the average value. This raises concern when trying to obtain solid evidence about the increases–decreases of houbara populations comparing different dates or study areas. The density of the Canary Island hubara bustard decreased significantly from 2004/2006 to 2011 in eight areas of Fuerteventura (Vega Vieja, Los Alares–Pocetas, Matas Blancas, Lorenzo– Diviso, Corralejo, Lajares and Fimapaire) and in two areas of Lanzarote (Argana and La Santa). Conversely, the density of the houbara significantly increased in three areas of Lanzarote (Zonzamas, Guatiza and Llano de las Maretas). As a whole, average population density did not differ significantly between 2004/2006 and 2011 in Fuerteventura (slight decrease of 29% in 2011), but there was a significant increase in Lanzarote (increase of 60% from 2004/2006 to 2011). The change in density from 2004/2006 to 2011 tended to be an increase in areas further from paved roads, and a decrease in locations predominantly covered by loose sandy soils.El establecimiento del estatus de conservación demanda la existencia de datos rigurosos y fiables acerca de los efectivos y las tendencias poblacionales, especialmente si se han de aplicar en islas en donde las especies tienen poblaciones pequeñas. Este trabajo analiza la valía de los resultados previos para la hubara utilizando el método de transectos lineales adyacentes separados 200 m, como puntos de partida adecuados para establecer tendencias poblacionales robustas en las 30 localidades principales de las islas de Lanzarote y Fuerteventura. Para ello se efectuaron censos en las mismas fechas (noviembre–diciembre 2011) y localidades estimando la probabilidad de detección. Este método de censo, que estima el máximo número de hubaras diferentes detectadas, proporciona valores de densidad muy poco subestimados (detección del 95,2% de las aves), por lo que las estimas previas de abundancia pueden ser consideradas como fiables (i.e., probable subestima media de un 5%). No obstante, los intervalos de confianza de las estimas de hubaras en las zonas prospectadas mediante un solo censo fueron enormes. Por tanto, con un solo censo por localidad y año no es posible obtener estimas precisas con un escaso margen de variabilidad en torno al valor medio. Esto plantea un problema considerable a la hora de obtener evidencias sólidas acerca de la certeza de los aumentos–disminuciones de los efectivos poblacionales al comparar fechas o zonas diferentes. La avutarda hubara ha disminuido significativamente su densidad de 2004/2006 a 2011 en ocho zonas de Fuerteventura (Vega Vieja, Los Alares–Pocetas, Matas Blancas, Lorenzo–Diviso, Corralejo, Lajares y Fimapaire) y en dos de Lanzarote (Argana y La Santa). Por el contrario, la densidad de la hubara ha aumentado significativamente en tres localidades de Lanzarote (Zonzamas, Guatiza y llano de Las Maretas). Globalmente, las estimas medias por isla no difirieron significativamente entre 2004/2006 y 2011 en Fuerteventura (leve disminución del 29% en 2011), pero sí en Lanzarote (aumento del 60% en 2011). El cambio de densidad entre los dos periodos de estudio tendió al incremento en 2011 en las localidades más alejadas de la carretera asfaltada más cercana, y tendió a la disminución en 2011 en las zonas con suelo predominantemente arenoso

Enhancing monitoring and transboundary collaboration for conserving migratory species under global change: The priority case of the red kite

Calls for urgent action to conserve biodiversity under global change are increasing, and conservation of migratory species in this context poses special challenges. In the last two decades the Convention on the Conservation of Migratory Species of Wild Animals (CMS) has provided a framework for several subsidiary instruments including action plans for migratory bird species, but the effectiveness and transferability of these plans remain unclear. Such laws and policies have been credited with positive outcomes for the conservation of migratory species, but the lack of international coordination and on-ground implementation pose major challenges. While research on migratory populations has received growing attention, considerably less emphasis has been given to integrating ecological information throughout the annual cycle for examining strategies to conserve migratory species at multiple scales in the face of global change. We fill this gap through a case study examining the ecological status and conservation of a migratory raptor and facultative scavenger, the red kite (Milvus milvus), whose current breeding range is limited to Europe and is associated with agricultural landscapes and restricted to the temperate zone. Based on our review, conservation actions have been successful at recovering red kite populations within certain regions. Populations however remain depleted along the southern-most edge of the geographic range where many migratory red kites from northern strongholds overwinter. This led us to a forward-looking and integrated strategy that emphasizes international coordination involving researchers and conservation practitioners to enhance the science-policy-action interface. We identify and explore key issues for conserving the red kite under global change, including enhancing conservation actions within and outside protected areas, recovering depleted populations, accounting for climate change, and transboundary coordination in adaptive conservation and management actions. The integrated conservation strategy is sufficiently general such that it can be adapted to inform conservation of other highly mobile species subject to global change.Financial and logistic support were provided by GREFA, IREC, UCLM (Universidad de Castilla-La Mancha), CSIC and MITECO.Peer reviewe

First diclofenac intoxication in a wild avian scavenger in Europe

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) with a well-known toxicity for old world vultures that ingest the carrion of domestic animals treated with it. Diclofenac intoxication was directly related to the dramatic declines in the populations of three native South Asian Gyps vulture species two decades ago. In 2013, this NSAID was authorised for veterinary use in Spain, which has the largest vulture populations in Europe. One of these species is the cinereous vulture (Aegypius monachus), which is classified as “near threatened” by the International Union for Conservation of Nature (IUCN). This species has been reintroduced and monitored in Catalonia (NE Spain) since 2007, and in 2020 its current population consisted of 15 breeding pairs and a total number of 61 individuals. In September 2020, one fledgling was found dead in the nest. Post-mortem examination revealed severe generalised visceral and articular gout, which was confirmed histologically. Diclofenac was detected at average concentrations of 26.5 ng/g in the liver and 51.4 ng/g in kidney replicates (n = 3), respectively. These findings support a diagnosis of fatal gout caused by diclofenac intoxication. This is the first case of diclofenac poisoning in Spain (and in Europe), in addition to being the first report of diclofenac poisoning in cinereous vultures. This case report, therefore, supports the need to closely monitor vulture populations and carry out strict regulatory measures with which to prevent these poisonings.The programme to reintroduce the cinereous vulture into the Catalan pre-Pyrenees has been funded by “Obra Social la Caixa” (through a contract with the “Generalitat de Catalunya”), the “Red Eléctrica de España” and the “Fundación Biodiversidad” from the Spanish Ministry of Ecological Transition and Demographic Challenge (MITECO).Peer reviewe

Spatial and Temporal Variability in Migration of a Soaring Raptor Across Three Continents

© Copyright © 2019 Phipps, López-López, Buechley, Oppel, Álvarez, Arkumarev, Bekmansurov, Berger-Tal, Bermejo, Bounas, Alanís, de la Puente, Dobrev, Duriez, Efrat, Fréchet, García, Galán, García-Ripollés, Gil, Iglesias-Lebrija, Jambas, Karyakin, Kobierzycki, Kret, Loercher, Monteiro, Morant Etxebarria, Nikolov, Pereira, Peške, Ponchon, Realinho, Saravia, Sekercioğlu, Skartsi, Tavares, Teodósio, Urios and Vallverdú. Disentangling individual- and population-level variation in migratory movements is necessary for understanding migration at the species level. However, very few studies have analyzed these patterns across large portions of species' distributions. We compiled a large telemetry dataset on the globally endangered Egyptian Vulture Neophron percnopterus (94 individuals, 188 completed migratory journeys), tracked across ~70% of the species' global range, to analyze spatial and temporal variability of migratory movements within and among individuals and populations. We found high migratory connectivity at large spatial scales (i.e., different subpopulations showed little overlap in wintering areas), but very diffuse migratory connectivity within subpopulations, with wintering ranges up to 4,000 km apart for birds breeding in the same region and each subpopulation visiting up to 28 countries (44 in total). Additionally, Egyptian Vultures exhibited a high level of variability at the subpopulation level and flexibility at the individual level in basic migration parameters. Subpopulations differed significantly in travel distance and straightness of migratory movements, while differences in migration speed and duration differed as much between seasons and among individuals within subpopulations as between subpopulations. The total distances of the migrations completed by individuals from the Balkans and Caucasus were up to twice as long and less direct than those in Western Europe, and consequently were longer in duration, despite faster migration speeds. These differences appear to be largely attributable to more numerous and wider geographic barriers (water bodies) along the eastern flyway. We also found that adult spring migrations to Western Europe and the Balkans were longer and slower than fall migrations. We encourage further research to assess the underlying mechanisms for these differences and the extent to which environmental change could affect Egyptian Vulture movement ecology and population trends

Spatial and Temporal Variability in Migration of a Soaring Raptor Across Three Continents

© Copyright © 2019 Phipps, López-López, Buechley, Oppel, Álvarez, Arkumarev, Bekmansurov, Berger-Tal, Bermejo, Bounas, Alanís, de la Puente, Dobrev, Duriez, Efrat, Fréchet, García, Galán, García-Ripollés, Gil, Iglesias-Lebrija, Jambas, Karyakin, Kobierzycki, Kret, Loercher, Monteiro, Morant Etxebarria, Nikolov, Pereira, Peške, Ponchon, Realinho, Saravia, Sekercioğlu, Skartsi, Tavares, Teodósio, Urios and Vallverdú. Disentangling individual- and population-level variation in migratory movements is necessary for understanding migration at the species level. However, very few studies have analyzed these patterns across large portions of species' distributions. We compiled a large telemetry dataset on the globally endangered Egyptian Vulture Neophron percnopterus (94 individuals, 188 completed migratory journeys), tracked across ~70% of the species' global range, to analyze spatial and temporal variability of migratory movements within and among individuals and populations. We found high migratory connectivity at large spatial scales (i.e., different subpopulations showed little overlap in wintering areas), but very diffuse migratory connectivity within subpopulations, with wintering ranges up to 4,000 km apart for birds breeding in the same region and each subpopulation visiting up to 28 countries (44 in total). Additionally, Egyptian Vultures exhibited a high level of variability at the subpopulation level and flexibility at the individual level in basic migration parameters. Subpopulations differed significantly in travel distance and straightness of migratory movements, while differences in migration speed and duration differed as much between seasons and among individuals within subpopulations as between subpopulations. The total distances of the migrations completed by individuals from the Balkans and Caucasus were up to twice as long and less direct than those in Western Europe, and consequently were longer in duration, despite faster migration speeds. These differences appear to be largely attributable to more numerous and wider geographic barriers (water bodies) along the eastern flyway. We also found that adult spring migrations to Western Europe and the Balkans were longer and slower than fall migrations. We encourage further research to assess the underlying mechanisms for these differences and the extent to which environmental change could affect Egyptian Vulture movement ecology and population trends