New Thesis defense with the GEDA!

Guillermo Gómez López had just obtained his Ph.D. at the University Complutense of Madrid with a thesis titled "Unravelling offspring sex ratios and survival in Old World vultures: insights from long-term monitoring" supervised by A. Sanz-Aguilar, G. Blanco y M. Carrete.  The thesis obtained the maximum note with laude. Congratulations Guillermo!!! Well done!!

New Publication on vultures !

Santangeli A, Fozzi I, De Rosa D, et al. Quantifying the regulation and cultural ecosystem services associated with Griffon Vultures Gyps fulvus in Sardinia, Italy. Bird Conservation International. 2024;34:e35. doi:10.1017/S0959270924000327 

 In a shell: The study shows the roles in carcass disposal, greenhouse gas mitigation, cultural identity, and ecotourism of Griffon Vultures in Sardinia, while emphasizing the need for their conservation to ensure sustainable human-wildlife coexistence.

Abstract: In the Anthropocene, recognising nature’s role in human well-being is pivotal for biodiversity conservation. Despite their significance, knowledge gaps persist regarding ecosystem services, even for well-studied species like vultures. Our study focuses on the Griffon Vulture Gyps fulvus in Sardinia, Italy, exploring their cultural and regulating services, including carcass disposal and resulting greenhouse gas (GHG) mitigation. Through surveys of natural reserve visitors and data on carcass provision and GHG emissions, we assess public perception, economic value, and environmental impacts associated with vultures. The public perception of Griffon Vultures is predominantly positive, with a strong acknowledgment of their role in disease prevention and carcass disposal, highlighting their contribution to regulation services. 

Furthermore, vultures are widely recognised as a key element characterising the agropastoral landscapes of Sardinia, underscoring their cultural importance. The economic evaluation, through willingness to pay for vulture-watching and photography opportunities, indicates a significant appreciation of these birds, with almost three-quarters of respondents willing to pay an entrance fee at vulture observation sites. We also show that supplanting the disposal role of vultures at studied feeding sites (during 2017–2022) would result in the emission of 96 tons of CO2 equivalent, which highlights the critical role of vultures in climate mitigation. This study not only sheds light on the ecological and cultural significance of Griffon Vultures in Sardinia but also underscores the economic and environmental benefits of their conservation. It emphasises the need for continued efforts in vulture conservation, integrating ecological, cultural, and economic perspectives to foster a sustainable coexistence between humans and wildlife.

New publication on vulture and mortality hotspots

Curk, T., [...] Santangeli, A., 2024 Integrating threat mapping and animal movement data to identify high-risk areas for endangered mobile species. https://doi.org/10.1111/acv.12980

In a shell: The work maps poisoning risks for the Lappet-faced Vultures in Southern Africa. It helps to identify hotspots that require conservation efforts. High food availability in these areas increases vulture risks of mortality.

Abstract:  Given the current biodiversity crisis, understanding how animals move across a landscape dotted with different anthropogenic threats and the consequences of those threats for animals is paramount to devising evidence-based conservation interventions. Vultures roam across large areas and are highly exposed to poisoning, which represents a particularly damaging form of wildlife crime. In this study, we introduce a framework for quantifying the exposure to threats and illustrate an example of poisoning risk as a threat in an endangered African vulture species, the Lappet-faced Vulture (Torgos tracheliotos). 

photo from ebird

We combined GPS tracking data of 19 individuals collected between 2012 and 2022 with food availability and spatial threat maps of both intentional (poachers directly targeting vultures) and unintentional (farmers aiming to kill carnivores, with vultures being secondarily affected) poisoning across most of Southern Africa. We identified poisoning hotspots in northern Botswana and south-eastern Namibia. These areas were also associated with a high number of vulture mortalities, providing additional support for poisoning risk. Northern Botswana and areas at the border between Botswana and South Africa were characterized by high food availability, potentially amplifying the mortality rate by attracting vultures from surrounding areas. Our results offer valuable insights for regional vulture conservation, together with a methodological framework for quantifying and mapping the spatial exposure to threats for mobile species of conservation concern, enabling improved targeting of conservation actions.

 

ECOPIC on Mallorcan vulture!

Cortés-Avizanda, A. and Tavecchia, G. 2021. New arrivals: natural colonization of an island by a large vertebrate. EcoPics 419 Front Ecol Environ doi:10.1002/fee.2398

The arrival of the Griffon vulture in Mallorca and the associated research project has been highlighted on the ECOPIC section of Fronters in Ecology and Environment here.

New publication on vultures!

Arrondo, E., García‐Alfonso, M., Blas, J., Cortes‐Avizanda, A., De La Riva, M., [...], Donazar, J.A. (2021), Use of avian GPS tracking to mitigate human fatalities from bird strikes caused by large soaring birds. Journal of Applied Ecology.  https://doi.org/10.1111/1365-2664.13893 

 Abstract:

1. Birds striking aircraft cause substantial economic loss worldwide and, more worryingly, human and wildlife fatalities. Designing effective measures to avoid fatal bird strikes requires in‐depth knowledge of the characteristics of this incident type and the flight behaviors of the bird species involved.
   
   
   
2. The characteristics of bird strikes involving aircraft crashes or loss of human life in Spain were studied and compared to flight patterns of bird monitored by GPS. We tracked 210 individuals of the three species that cause the most crashes and human fatalities in Spain: griffon and cinereous vultures (Gyps fulvus and Aegypius monachus) and white storks (Ciconia ciconia).
3. All the crashes involved general aviation aircraft, while none were recorded in commercial aviation. Most occurred outside airport boundaries, at midday and in the warmest months, which all correspond with the maximum flight activity of the studied species.
4. Bird flight altitudes overlapped the legal flight altitude limit set for general aviation.
5. Policy implications: Mitigation of fatal bird strikes should especially address the conflict between general aviation and large soaring birds. Air transportation authorities should consider modifying the flight ceiling for general aviation flights above the studied species’ maximum flight altitude. Moreover, policymakers should issue pilots with recommendations regarding the dates and times of peak activity of large soaring bird species to improve flight safety.
   

New publication on Vultures and lead!

Arrondo, E., [..], Cortés-Avizanda, A., [...], Donázar, J.A. 2020. Dust and bullets: Stable isotopes and GPS tracking disentangle lead sources for a large avian scavenger. Enviornmental Pollution, in press https://doi.org/10.1016/j.envpol.2020.115022

Abstract: Lead intoxication is an important threat to human health and a large number of wildlife species. Animals are exposed to several sources of lead highlighting hunting ammunition and lead that is bioavailable in topsoil. Disentangling the role of each in lead exposure is an important conservation issue, particularly for species potentially affected by lead poisoning, such as vultures. The identification of lead sources in vultures and other species has been classically addressed by means of stable-isotope comparisons, but the extremely varied isotope signatures found in ammunition hinders this identification when it overlaps with topsoil signatures.

In addition, assumptions related to the exposure of individual vultures to lead sources have been made without knowledge of the actual feeding grounds exploited by the birds. Here, we combine lead concentration analysis in blood, novel stable isotope approaches to assign the origin of the lead and GPS tracking data to investigate the main foraging grounds of two Iberian griffon vulture populations (N = 58) whose foraging ranges differ in terms of topsoil lead concentration and intensity of big game hunting activity. We found that the lead signature in vultures was closer to topsoil than to ammunition, but this similarity decreased significantly in the area with higher big game hunting activity. In addition, attending to the individual home ranges of the tracked birds, models accounting for the intensity of hunting activity better explained the higher blood lead concentration in vultures than topsoil exposure. In spite of that, our finding also show that lead exposure from topsoil is more important than previously thought

GEDA at AESA

Ainara Cortés-Avizanda presented her project on the space use of vultures in Mallorca at the "Agencia Estatal de Seguridad Aerea" (AESA).

New Publication on rewilding and scavangers!

Arrondo, E., Morales-Reyes, Z., Moleón, M., Cortés-Avizanda, A., Donázar, J.A. and Sánchez-Zapata, J.A. 2019 Rewilding traditional grazing areas affects scavenger assemblages and carcass consumption patterns Basic and App Ecol, https://doi.org/10.1016/j.baae.2019.10.006

Abstract: The abandonment of traditional livestock farming systems in Mediterranean countries is triggering a large-scale habitat transformation, which, in general, consists of the replacement of open grazing areas by woodlands through non-managed regeneration. As a consequence, wild ungulates are occupying rapidly the empty niche left by domestic ungulates. Both types of ungulates represent the main trophic resource for large vertebrate scavengers. However, a comparison of how vertebrate scavengers consume ungulate carcasses in different habitats with different ungulate species composition is lacking. This knowledge is essential to forecast the possible consequences of the current farmland abandonment on scavenger species. Here, we compared the scavenging patterns of 24 wild and 24 domestic ungulate carcasses in a mountainous region of southern Spain monitored through camera trapping. Our results show that carcasses of domestic ungulates, which concentrate in large numbers in open pasturelands, were detected and consumed earlier than those of wild ungulate carcasses, which frequently occur in much lower densities at more heterogenous habitats such as shrublands and forest. Richness and abundance of scavengers were also higher at domestic ungulate carcasses in open habitats. Vultures, mainly griffons (Gyps fulvus), consumed most of the carcasses, although mammalian facultative scavengers, mainly wild boar (Sus scrofa) and red fox (Vulpes vulpes), also contributed importantly to the consumption of wild ungulate carcasses in areas with higher vegetation cover. Our findings evidence that the abandonment of traditional grazing may entail consequences for the scavenger community, which should be considered by ecologists and wildlife managers.

See a press note (in Spanish) here

New Publication on scavangers in the Anthropocene!

Sebastián-González, E., [...], Cortés-Avizanda, A., [...] 2019. Scavenging in the Anthropocene: human impact drives vertebrate scavenger species richness at a global scale. Global Change Biology https://doi.org/10.1111/gcb.14708

Photo: Chris Johns, Nat. Geogr. Education

Abstract: Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. 

Here, we aim to describe large‐scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion‐consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using 2,485 carcasses monitored between 1991‐2018. First, we evaluated how scavenger richness (number of species) and diversity (Shannon diversity index) varied among seasons (cold vs. warm, wet vs. dry). Then, we studied the potential effects of human impact and a set of macroecological variables related to climatic conditions on the scavenger assemblages. Vertebrate scavenger richness ranged from species‐poor assemblages to species‐rich (4 ‐ 30 species). Both scavenger richness and diversity also showed some seasonal variation. However, in general, climatic variables did not drive latitudinal patterns, as scavenger richness and diversity were not affected by temperature or rainfall. Rainfall seasonality slightly increased the number of species in the community, but its effect was weak. Instead, the human impact index included in our study was the main predictor of scavenger richness. Scavenger assemblages in highly human‐impacted areas sustained the smallest number of scavenger species, suggesting human activity may be over‐riding other macroecological processes in shaping scavenger communities. Our results highlight the effect of human impact at a global scale. As species‐rich assemblages tend to be more functional, we warn about possible reductions in ecosystem functions and the services provided by scavengers in human‐dominated landscapes in the Anthropocene.