Experimental food subsidies keep eagles inside protected areas: implications for conservation and resource management

The conservation and management of mobile species, populations and dynamic habitats, presents significant challenges since such species face diverse threats during various stages of their life cycle. Protected areas (PAs) are essential tools in conservation efforts, aiming to preserve native species and their habitats. However, larger mobile animals, such as the Bonelli's eagle (Aquila fasciata), may require much larger areas outside PAs for essential life moments, including foraging, resting, and wintering. As a result, the efficacy of PAs in conserving such species may be questionable. We designed an experiment in an eastern Spain PA that is home to nesting Bonelli's eagles to determine if increasing food availability through experimental feeding within the PA could result in an effective reduction of space use outside the protected area by the eagles and lead to reduce death risk. Over the period of 2016 to 2021, we tracked 10 Bonelli's eagles from six different territories using GPS-GSM transmitters. We evaluated their space use before, during, and after the feeding experiment. Our results indicate that the availability of food within PAs restricted the eagles' movement, resulting in a higher concentration of locations inside the PAs. The eagles spent less time outside the PAs when they were fed and less time in highly human-dominated habitats. Consequently, this reduced mortality risks that were higher outside the PAs. Our findings suggest that management decisions aimed at increasing food availability within PAs, could be critical in conserving endangered species populations such as the Bonelli's eagle in Mediterranean landscapes.Fieldwork seasons (2017 – 2018) were partially supported by the Wildlife Service of the Valencian Community Regional Government (Conselleria d'Agricultura, Desenvolupament Rural, Emergència Climàtica i Transició Ecològica, Generalitat Valenciana, Spain). Red Eléctrica de España provided financial support to track Bonelli's eagles under the supplementary feeding project. The corresponding author A. L-P. is supported by a Val I+D predoctoral grant (ACIF/2020/051) and an internship grant (CIBEFP/2021/75), both funded by the Generalitat Valenciana (Spain). This paper is part of the Ph.D. thesis of A. López-Peinado at the University of Valencia (Spain)

Analysis of monoterpenoids in inclusion complexes with β-cyclodextrin and study on ratio effect in these microcapsules.

In recent studies, the insecticide activity against some stored products pests of monoterpenoids, such as linalool, S-carvone, camphor, geraniol, γ-terpinene and fenchone, and phenylpropanoids, like E-anethole and estragole, has been proved. Currently, applications of these volatile compounds are complicated due to their chemical and physical properties. This is one of the major problems for their use as insecticides; therefore, microencapsulation could be the solution to problems of stability, evaporation and release. Microencapsulation of these chemicals was carried out with β-cyclodextrin using a chemical precipitation method at four different ratios (β-cyclodextrin: monoterpenoids), 1.33:1, 3.33:1, 4.66:1 and 6.66:1 (w/w) in order to determine the ratio effect. This study establishes that encapsulation at the ratio of 3.33:1 to linalool and γ-terpinene was higher, whereas S-carvone, camphor, E-anethole, geraniol, estragole and fenchone showed the greatest encapsulation when the ratio was 6.66:1. Furthermore, the efficiency of encapsulation was estimated by measuring the content of the compounds in the powder by gas chromatography. The maximum inclusion efficiency of β-cyclodextrin was reached by camphor (52%) followed by geraniol (34%) using 10 g of β-cyclodextrin and linalool (31%) using 5 g of this matrix. The present study indicates that natural products such as monoterpenoids or phenylpropanoids could be microencapsulated in an efficient way using an appropriate amount of β-cyclodextrin. Keywords: Microencapsulation, β-cyclodextrin, Camphor, Geraniol and Linaloo

Post-fledging dependence period and onset of natal dispersal in Bearded Vultures (Gypaetus barbatus): new insights from GPS satellite telemetry.

Utilizamos telemetría satelital para estudiar el periodo de dependencia post emplumamiento de tres individuos silvestres y seis individuos cautivos de Gypaetus barbatus. El primer vuelo tuvo lugar cuando los pollos tenían 126 ± 7 días de edad (rango  =  111-134 días) y el inicio de la dispersión ocurrió a los 193 ± 40 días desde el primer vuelo (rango  =  143-231 días). Los jóvenes permanecieron en sus áreas natales (o de liberación, en el caso de aves criadas en cautiverio) durante los primeros dos meses desde la fecha de emplumamiento. Luego, comenzaron a incrementar progresivamente la distancia a sus áreas natales; durante este tiempo, la mayoría de los desplazamientos de larga distancia (>15 km) tuvieron lugar antes del mediodía. Los tamaños de las áreas de acción registrados en este estudio fueron superiores a los descritos con anterioridad para la especie, principalmente debido a la diferencia en los métodos de rastreo empleados: la telemetría satelital permitió la detección de movimientos de larga distancia más allá del rango de medición del rastreo por radio convencional. Finalmente, la adquisición de la independencia (i.e., emancipación) se solapó con la siguiente temporada de cría de los adultos