Winter ranging behaviour of a greater spotted eagle (Aquila clanga) in southeast Spain during four consecutive years

Abstract

Knowing the winter behaviour is essential for deciding on conservation strategies for threatened migratory species such as the greater spotted eagle (Aquila clanga). Fidelity and inter-annual variation in winter home range of an Estonian greater spotted eagle were studied during the first four years of its life by means of GPS satellite telemetry in south-eastern Spain. Results show the eagle exploited a small area (12.7 km 2 , 95% kernel) with high inter-annual fidelity during all winter stages. The A. clanga preferred marshes and water bodies and avoided irrigated crops and urban areas. Waterfowl hunting did not show any effect on the spatial pattern of the eagle's behaviour, although water level management in reservoirs could influence their use by the A. clanga. Our study highlights that the wintering home range may be limited to a small suitable habitat patch where human activities, especially water reservoir management, should be regulated.Abstrakt: Nevyhnutným predpokladom efektívnych ochranárskych opatrení je poznanie zimného správania ohrozeného migrujúceho druhu, akým je orol hrubozobý (Aquila clanga). Fidelita a medziročná variabilita charakteristík zimného okrsku jedinca orla hrubozobého pochádzajúceho z Estónska sa sledovala počas prvých štyroch rokov jeho života pomocou GPS-satelitnej telemetrie v juhovýchodnom Španielsku. Z výsledkov vyplýva, že orol využíval počas zimy len malé územie (12,7 km 2 , 95 %-ný kernel) s vysokou medziročnou fidelitou. A. clanga preferoval mokrade a vodné plochy a vyhýbal sa zavlažovaným poľným kultúram a urbanizovaným územiam. Poľovačky na vodné vtáctvo neovplyvnili charakter priestorového správania orla, avšak výška vodnej hladiny vodných rezervoárov mala vplyv na ich využitie sledovaným jedincom. Z výsledkov našej štúdie možno zdôrazniť, že zimný domovský okrsok môže byť priestorovo obmedzený na malé plochy vhodného habitatu, kde by ľudská čin-nosť, najmä manažment vodných rezervoárov, mala byť regulovaná.

Spatial and temporal differences in migration strategies among endangered European Greater Spotted Eagles Clanga clanga

“…Indeed, Greater Spotted Eagles winter in small, restricted habitat patches (Pérez-Garcia et al . 2014, Maciorowski et al . 2019), but there are no data on intraspecific competition at wintering sites; instead, several birds are recorded to share roosting and foraging sites in wintering grounds.…”

The importance of wetlands for the Greater Spotted Eagle Clanga clanga wintering in the Mediterranean Basin

“…The model built on telemetry data strongly agreed with literature data and ringing recoveries from European individuals, and therefore can be used for planning future counts of the wintering population. However, one fact has to be considered – the GSE breeding population is shifting eastwards towards the Mediterranean Basin, and telemetry studies showed GSE are mainly moving south and south-east during the autumn migration (Maciorowski et al 2014), while only single birds from Estonia and Poland were heading south-west (Pérez-García et al 2014, Maciorowski unpubl. ringing recoveries).…”

“…comm.). In scarce wintering sites in Spain this species also prefers marshes, wetlands and coastal lagoon, abundant in waders, coots and rats (Pérez-García et al 2014). Accordingly, the winter preference of the GSE towards marshes may result from two factors.…”

“…The other broad wintering area is the Mediterranean Basin, especially the Middle East and southern Europe. In Europe most individuals are seen in Greece, while some are also recorded in Spain, France, Italy, Serbia, Montenegro, Romania and Albania (Hallmann 1989, Francois 1992, Handrinos and Akriotis 1997, Trebušak et al 1999, Yeatman-Berthelot 2000, Alivizatos et al 2004, Schneider-Jacoby et al 2006, De Dochy 2008, Perez-Garcia et al 2014, De Juana and Garcia 2015, Marco and Pérez-García 2017). In the Mediterranean Basin it also winters in the Asian part of Turkey and in the Middle East, mainly Israel (Allon and Shirihai 1991, Shirihai 1996, Dan et al 2005, Kirwan et al 2008a, 2008b).…”

Movements of a male greater spotted eagle (Clanga clanga) during its 2nd and 3rd calendar years

“…Greater spotted eagles tracked in those studies migrated south in autumn, some southwest towards Iberia, others south and south east towards Greece, the Balkan countries, Turkey and the Levant. Some birds migrated only as far as the northern rim of the Mediterranean, but others wintered in Arabia and north east and East Africa, as far south as Zambia (Meyburg et al 1998, PérezGarcía et al 2014. Tracking studies from farther east are few and of limited duration, but show birds from wintering grounds in Arabia migrating toward summering areas in northern Kazakhstan, and bordering areas of Russia in eastern Europe and western Siberia (Meyburg et al 1995, Strick et al 2011.…”