0000000001312818
AUTHOR
Rubén Limiñana
Ecological specialization to fluctuating resources prevents long-distance migratory raptors from becoming sedentary on islands
[Background]: The adaptive transition between behavioral strategies, such as the shift from migratoriness to sedentariness, remains an outstanding question in evolutionary ecology. Density-dependent variation in the age of first breeding has been proposed as a feasible mechanism through which long-lived migratory birds with deferred sexual maturity should become sedentary to persist on islands. Although this pattern seems to hold for most raptors and herons, a few exceptions have been identified. One of these exceptions is the Eleonora's falcon, a long-distance migratory bird, which shows one of the most peculiar adaptations in the timing of reproduction and food requirements among raptors.…
Pre-Migratory Movements of Adult Montagu's HarriersCircus pygargus
Pre-migratory and migratory movements of Montagu's Harrier Circus pygargus, a long-distance migrant, are poorly documented by ring recoveries and observations. In the present study, we tagged 10 adult Montagu's Harriers in NE Spain with satellite transmitters and tracked their movements until their arrival on the wintering grounds. To identify the end of the breeding season and the onset of the migration based on our satellite-telemetry data we developed and applied a statistical approach, defining the time period between these two events as the pre-migratory stage. We then compared habitat preferences during the breeding season and the pre-migratory stage. The duration of the pre-migratory…
Interspecific comparison of the performance of soaring migrants in relation to morphology, meteorological conditions and migration strategies.
This is an open-access article distributed under the terms of the Creative Commons Attribution License.-- et al.
Large birds travel farther in homogeneous environments
Aim: Animal movement is an important determinant of individual survival, population dynamics and ecosystem structure and function. Nonetheless, it is still unclear how local movements are related to resource availability and the spatial arrangement of resources. Using resident bird species and migratory bird species outside the migratory period, we examined how the distribution of resources affects the movement patterns of both large terrestrial birds (e.g., raptors, bustards and hornbills) and waterbirds (e.g., cranes, storks, ducks, geese and flamingos). Location: Global. Time period: 2003–2015. Major taxa studied: Birds. Methods: We compiled GPS tracking data for 386 individuals across 3…
Wintering habitats of Eleonora's FalconsFalco eleonoraein Madagascar
[Capsule]: Eleonora's Falcons wintering in Madagascar selected degraded humid forests and cultivated areas close to pristine humid forest. [Aims]: To identify the habitat preferences of Eleonora's Falcon Falco eleonorae on their wintering grounds in Madagascar, and to use this information to gain insights into the conservation priorities of this species. [Methods]: A total of 11 Eleonora's Falcons were captured in Spain in 2007 and 2008 and equipped with solar-powered satellite transmitters. We obtained information on five complete wintering events for three birds, two of them tracked for two consecutive years. Data were analyzed using geographic information system-based cartography. [Resul…
Diurnal timing of nonmigratory movement by birds: the importance of foraging spatial scales
Timing of activity can reveal an organism's efforts to optimize foraging either by minimizing energy loss through passive movement or by maximizing energetic gain through foraging. Here, we assess whether signals of either of these strategies are detectable in the timing of activity of daily, local movements by birds. We compare the similarities of timing of movement activity among species using six temporal variables: start of activity relative to sunrise, end of activity relative to sunset, relative speed at midday, number of movement bouts, bout duration and proportion of active daytime hours. We test for the influence of flight mode and foraging habitat on the timing of movement activit…
Regional and age-dependent differences in the effect of wind on the migratory routes of Eleonora's Falcon.
During migration, birds can show different responses to wind in relation to distance to the goal, experience, ecological barriers and visibility of landmarks. We analysed the effect of wind (tailwinds and crosswinds) on daily movement rates (forward and perpendicular) of Eleonora’s falcons using ARGOS satellite telemetry, during their trans-continental autumn migration to Madagascar, in relation to the different crossed regions and individuals’ age class. Our results showed that the effect of wind on daily movement rates was not uniform, being stronger in the farthest region from the migration goal, the Sahara desert, with adults being more affected than juveniles in this region. In the Sah…
The First Case of Successful Breeding of a Golden EagleAquila chrysaetosTracked from Birth by Satellite Telemetry
The natal dispersal of a Golden Eagle from its natal eyrie to the site where it reproduced for the first time was monitored. After covering > 16 000 km2 in its three years of juvenile dispersal, and despite flying > 130 km from its natal site, the eagle finally settled in a vacant territory just 26 km away from the place where it had hatched. Almost 95% of the total dispersal area was visited for the first time during the first year of tracking; less than 40% of the disper- sal area was used during the remainder of the dispersal period. During dispersal the eagle regularly visited territories occupied by adult Golden Eagles. Previous records of the occupancy of the territory the eagle curre…
Enseñanza y aprendizaje del Consumo Sostenible como motor del cambio ante las desigualdades sociales y el deterioro ambiental
El modelo insostenible de consumo en el que se basa la sociedad actual ha derivado en la crisis climática, social y ambiental que está soportando nuestro planeta desde hace décadas y que ha generado profundas desigualdades sociales y conflictos internacionales, como el que existe en el este del Congo, que es el conflicto bélico que más vidas se ha cobrado desde la Segunda Guerra Mundial con más de cinco millones de fallecidos y millones de refugiados que huyen de la violencia extrema de los grupos armados que controlan la extracción de coltán en ese territorio. Ante esta situación, los y las docentes que estamos formando a futuros maestros y maestras no podemos mirar hacia otro lado y hemos…
Data from: Large birds travel farther in homogeneous environments
Aim: Animal movement is an important determinant of individual survival, population dynamics, and ecosystem structure and function. Yet it is still unclear how local movements are related to resource availability and the spatial arrangement of resources. Using resident bird species and migratory bird species outside of the migratory period, we examined how the distribution of resources affect the movement patterns of both large terrestrial birds (e.g., raptors, bustards, hornbills) and waterbirds (e.g., cranes, storks, ducks, geese, flamingos). Location: Global Time Period: 2003 - 2015 Major taxa studied: Birds Methods: We compiled GPS tracking data for 386 individuals across 36 bird specie…