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Published an article in the journal Bird Conservation International about the demographic evolution of the Egyptian vulture in Catalonia
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A
new study about the increasing population of the Egyptian vulture in
Catalonia entitled "Identifying key demographic parameters for the
viability of a growing population of the endangered Egyptian Vulture
Neophron percnopterus" has been published in the journal Bird
Conservation International. The paper explains the growth experienced
by the population of this species in Catalonia and also it is carried
out an Analysis of the Viability of the species to make predictions of
the conservation status of the population in the future.
The
Egyptian vulture population in central and eastern Catalonia has
increased from 1 to 22 pairs during the period 1988-2012, and today is
still growing. To explain this population increase, a series of models
based on different demographic parameters (population growth rate,
survival and productivity) have been designed to simulate various
scenarios that could have happened in the last 20 years. One of the
main conclusions of the models is that to explain the population
observed growth rate, survival of adult individuals in our population
should be higher than adult survival of individuals from other parts of
the Iberian Peninsula (specifically the Ebro valley).
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Adult Egyptian vulture in flight. Photo: Kiku Parés (Conservation Biology Group of the UB)
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One
possible explanation for this high adult survival would be that in our
area the use of poisons is lower than in other areas of the peninsula,
where poisoning is the main cause of unnatural mortality of adult
individuals. However, the models also suggest that the arrival of
individuals from other populations could contributed to the demographic
increase, since a high adult survival is not enough to explain the
population growth experienced in recent years.
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a Population Viability Analysis was carried out to predict the future
of the Egyptian vulture in Catalonia under different scenarios. This
analysis establishes that if conditions do not change and vital
parameters of the population remain, all scenarios predict that the
population will maintained or continue to grow, depending on whether
immigrants are still arriving to the population or do-leave it.
This
positive trend of the population of eastern Catalonia is an exception
to the overall situation of the Egyptian vulture, a species classified
as 'endangered' by the IUCN for its declining in a wide part of its
range. For this reason, it is important to highlight that although the
actual situation of the population is favorable is still susceptible
and any change could cause a population decline again.
This
study was carried out by the Conservation Biology Group (Joan Real,
Antonio Hernández-Matías and Helena Tauler) together with expert
naturalists from “Grup de Naturalistes d’Osona” (Jordi Baucells and
Carles Martorell) and from Berguedà and Solsonès (Per Aymerich and Joan
Santandreu).
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Evolution of the number of occupied territories of Egyptian vulture in central and eastern Catalonia during 1988-2012. Source: Tauler et al., 2015
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Thanks to the rest of
naturalists that provided information for the study (S. Arís, J. Arrey,
E. Bassols, M. Batriu, J. Bosch, J. Calaf, J. Faus, J. Fort, J. Garcia
Petit, J. Gracia, P. Isern, G. Lampreave, T. Mampel, D. Mañas, J.
Montserrat, A. Miño, F. Parés and A. Peris), to the Natural Parcs and
institutions that participated (“Parc Natural de Montserrat”, “Parc
Natural de Sant Llorenç de Munt”, “Parc Natural de la Zona Volcànica de
la Garrotxa”, “Consorci dels Espais Naturals del Ripollès”), as well as
the “Institut Català d’Ornitologia” to make avaliable its data base ornitho.cat.
Thank to “Red Eléctrica de España” the support received and especially
to Mercedes Gil Pozo her interest on the monitoring and the development
of the project. Helena Tauler was supported by a predoctoral grant
IRBIO-UB (APIF 2014).
For further information:
- Tauler,
H., Real, J., Hernández-Matías, A., Aymerich, P., Baucells, J.,
Martorell, C. & Santandreu, J. 2015. Identifying key
demographicparameters for the viability of a growing population of the
endangered Egyptian Vulture Neophron percnopterus. Bird Conservation International, doi:10.1017/S0959270914000392 pdf
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