This blog tracks the scientific activity of the Animal Demography and Ecology Unit of the IMEDEA (CSIC-UIB). Contents on animal demography, capture-recapture, APHIS, upcoming workshop, publications
Friday, 13 October 2023
Shearwaters on the news!
Thursday, 5 October 2023
New publication on gulls as seed dispersers!
Ando, H., Martín-Vélez, V., Tavecchia, G., Traveset, A., Jiménez-Martín, I., Igual, J. M., Martínez-Abraín, A., & Hervías-Parejo, S. (2023). Gulls contribute to olive seed dispersal within and among islands in a Mediterranean coastal area. Journal of Biogeography, 00, 1–9. https://doi.org/10.1111/jbi.14735
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| Photo: wikipedia.org |
Tuesday, 26 September 2023
New publication on gulls and landfills!
Delgado, S., Tavecchia, G., Herrero, A. et al. Model projections reveal a recent decrease in a yellow-legged gull population after landfill closure. Eur J Wildl Res 69, 99 (2023). https://doi.org/10.1007/s10344-023-01723-w
In a shell: The study reveals that the closure of local landfills leads to a decline in survival rates, especially in younger birds, ultimately causing a population decrease with continuing consequences.
Abstract: The food available in open-air landfills, one of the most common predictable anthropogenic food subsidies (PAFS), can have a profound impact on animal biodiversity. Understanding how and to what extent PAFS affect wildlife is crucial for a sustainable management of resources. Most large gulls behave as opportunistic foragers and constitute a good avian model to analyze the effect of PAFS reduction on animal populations.
Using individual data from a yellow-legged gull population of the Basque coast (northern Iberia) collected over a 15-year period, we estimated survival and reproductive parameters and used them to parameterize an age-structured population model to explore the effects of the local landfill closure. Local survival probability declined with time as a consequence of the progressive closure of the local landfill sites. The top-ranked models included a quadratic function of time, suggesting an acceleration of mortality during the later years, especially in juveniles, while survival in adults was linear. An effect more pronounced in first year birds than in older birds. Population models predict a decrease of the population and confirmed a greater sensitivity of the population growth rate to adult survival probability. Overall, our results suggest that the reduced carrying capacity of the system resulted after landfill closures have caused a population decline which is expected to continue in the near future.Tuesday, 19 September 2023
New publication on illegal and accidental hunting!
Pérez‐García, J. M., Sebastián‐González, E., Rodríguez‐Caro, R., Sanz‐Aguilar, A., Botella, F. (2023). Blind shots: non‐natural mortality counteracts conservation efforts of a threatened waterbird”. Animal Conservation. https://doi.org/10.1111/acv.12906
In a shell: The study found that 60% of recorded mortalities of the marbled teal was due to non-natural causes, including illegal shooting. Hunters might kill marbled teals accidentally while shooting other game species. The study highlights the need to reduce illegal shootings to establish a viable population of marbled teal.
Abstract: Waterbirds are particularly affected by the high hunting pressure they face in many regions, which in some cases is compromising conservation actions for threatened species. The marbled teal Marmaronetta angustirostris is one of the most endangered waterbirds in Europe. In order to restore its population, several conservation actions have recently been undertaken, including a population reinforcement programme in Spain using captive-bred birds. With the aim of assessing the success of the reinforcement programme to establish a long-term self-sustaining population, we identified mortality causes of marbled teal, evaluated the survival of individual birds of the reinforcement programme and estimated the viability of the population under different management scenarios.
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| Pohto: Wikipedia.com |
We used data from wild and captive-bred individuals tracked by GPS since 2018 (n = 42) and from a mark–recapture programme initiated in 2015 (n = 297). We recovered 15 dead birds or transmitters: 20% died of natural causes, 60% of non-natural causes (including all anthropic causes) and 20% of unknown causes. Furthermore, the GPS tags of 24 birds unexpectedly stopped transmitting without any indication of malfunction, and for 66.7% of these disappeared birds, the cessation was suspected to be caused by illegal shooting. Survival during the hunting season was higher for males (31.3%) than for females (12.5%), and for the wild (50%) than for the captive-bred birds (9.4%), probably due to differences in migration patterns to North Africa. Population viability models revealed that maintaining the breeding population at the current mortality rates is only possible with a permanent release programme of captive-bred individuals, and that in order to establish a self-sustaining population, non-natural mortality would have to be reduced by at least 40%. We recommend management measures to reduce marbled teal mortality, such as limiting legal hunting to hours with clear visibility, prosecuting illegal shootings, controlling exotic predators and improving water management to reduce disease outbreaks. Some improvements can be implemented in captive-breeding programmes, such as earlier release times and incorporating anti-predator training.
A press note (in Spanish) here
Monday, 18 September 2023
New publication on the effect of protected areas!
Santangeli, A., Weigel, B., Antão, L.H. et al. Mixed effects of a national protected area network on terrestrial and freshwater biodiversity. Nat Commun 14, 5426 (2023). https://doi.org/10.1038/s41467-023-41073-4
In a shell: Only a small fraction of species benefits of protected areas and it is not linked to species traits or conservation status. This indicates that additional measures like expanding coverage, enhancing connectivity, and better management are essential to address the broader biodiversity crisis effectively.
Abstract: Protected areas are considered fundamental to counter biodiversity loss.
However, evidence for their effectiveness in averting local extinctions
remains scarce and taxonomically biased.
We employ a robust
counterfactual multi-taxon approach to compare occupancy patterns of 638
species, including birds (150), mammals (23), plants (39) and
phytoplankton (426) between protected and unprotected sites across four
decades in Finland. We find mixed impacts of protected areas, with only a
small proportion of species explicitly benefiting from
protection—mainly through slower rates of decline inside protected
areas. The benefits of protection are enhanced for larger protected
areas and are traceable to when the sites were protected, but are mostly
unrelated to species conservation status or traits (size, climatic
niche and threat status). Our results suggest that the current protected
area network can partly contribute to slow down declines in occupancy
rates, but alone will not suffice to halt the biodiversity crisis.
Efforts aimed at improving coverage, connectivity and management will be
key to enhance the effectiveness of protected areas towards bending the
curve of biodiversity loss.
Wednesday, 13 September 2023
New publication on plastic and Storm Petrels!
Clark, B.L., Carneiro, A.P.B., [...] Sanz-Aguilar, A.,[...] Rotger, A., et al. Global assessment of marine plastic exposure risk for oceanic birds. Nat Commun 14, 3665 (2023). https://doi.org/10.1038/s41467-023-38900-z
In a shell: Unevenly distributed plastic pollution in the ocean can impact on vulnerable marine organisms, particularly petrel seabirds. High exposed zones were found in the Mediterranean, Black Seas, Pacific oceans, South Atlantic, and Indian Ocean. We emphasize the need for international collaboration to mitigate these risks.
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| Photo: Y.Muzika - eBird |
Thursday, 7 September 2023
The gender equality problem on the news!
Here (in catalan) an intervew to A. Sanz-Aguilar who co-signed the manuscript.
Below other press releases in csatellano and english:
Monday, 28 August 2023
New publication on global changes and distribution shifts!
Marjakangas EL, Bosco L, Versluijs M, Xu Y, Santangeli A, [...] and Lehikoinen A. 2023 Ecological barriers mediate spatiotemporal shifts of bird communities at a continental scale. Proc Natl Acad Sci USA, 120 (23):e2213330120. doi: 10.1073/pnas.2213330120.
In a shell: Overlooked barriers such as landscapes' edges, coastlines, and elevation, hinder animal movement and constrain adaptations. This study emphasizes the need to consider these barriers for predicting future changes in animal communities.
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| From: wikipedia.com |
Abstract: Species’ range shifts and local extinctions caused by climate change lead to community composition changes. At large spatial scales, ecological barriers, such as biome boundaries, coastlines, and elevation, can influence a community's ability to shift in response to climate change. Yet, ecological barriers are rarely considered in climate change studies, potentially hindering predictions of biodiversity shifts. We used data from two consecutive European breeding bird atlases to calculate the geographic distance and direction between communities in the 1980s and their compositional best match in the 2010s and modeled their response to barriers. The ecological barriers affected both the distance and direction of bird community composition shifts, with coastlines and elevation having the strongest influence. Our results underscore the relevance of combining ecological barriers and community shift projections for identifying the forces hindering community adjustments under global change. Notably, due to (macro)ecological barriers, communities are not able to track their climatic niches, which may lead to drastic changes, and potential losses, in community compositions in the future.
Subscriptions to CMRR 2026 workshop open!
Subscription to the upcoming workshop on CMRR analysis, now open. INTRODUCTORY COURSE : 23 - 27 Nov. 2026, Mallorca, Spain (places: 20,...
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Mingozzi, T., Storino, P., Venuto, G., Massolo, A., Tavecchia, G., 2021. Climate warming induced a streth of the breeding season and an incr...
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S Bolumar and A Santangeli are participating to the XXII Italian Ornithology Conference in Lecce
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Here is a short video by A. Rotger of the exhibition at the Natural History Museum in Soller "When data speak". The exhibition w...






