We tracked a breeding adult female lesser spotted eagle (Clanga pomarina) from Germany using GPS technology, and provide details of her collision with a small aircraft at Rzeszów (SE Poland) during April 2016, when she was migrating towards her breeding territory. The ultimate fate of the bird was not established until the tag was found by chance and the data were recovered. Bird strikes are a global problem with sometimes lethal consequences for animals and people. This account highlights the way technology allows us to closely monitor events during bird migration, and document human-raptor interactions. The collision illustrates how food availability might affect bird-strike risk, and indicates that removing animal carcasses from the vicinity of airports could reduce that risk. We discuss the data in relation to risks faced by lesser spotted eagles (and other soaring birds) of collision with aircraft, especially along flyways during migration seasons.
Cainism, nestling management in Germany in 2004-2007 and satellite tracking of juveniles in the Lesser Spotted Eagle (Aquila pomarina)
The Lesser Spotted Eagle belongs to a species with obligatory cainism, which means that in the natural state it is rare that two young eagles fledge, although as a rule two chick's hatch. The breeding population in Germany is at the western edge of the species' range and is declining (a 23% decrease between 1993 and 2007). Local extinction can be anticipated and therefore nestling management has been implemented in the German federal state of Brandenburg since 2004 as a conservation measure by using human intervention to prevent the death of the younger sibling. This is in addition to other methods such as nest-site protection, habitat preservation, legislation etc. Furthermore, in 2007, second hatched eagle chicks (Abels) from Latvia were translocated for the first time. The managed pairs (nests physically inspected) were on average more successful than the unmanaged pairs (nests not physically inspected). It cannot be determined as to whether the inspection of the nests had a negative effect on breeding. Breeding success of the pairs present in Brandenburg, including non-breeders, increased by 57 % in 2007 due to nestling management, and that of the managed pairs alone by 67 %. In 2007 the behaviour of six young eagles was studied using satellite telemetry. This study determined that the Abels migrated as well as the first hatched eagle chicks (Cains), and that their survival chances were equally good. The Abels imported from Latvia migrated in two out of three cases along the same route as the German Lesser Spotted Eagles to the Bosporus. One Latvian Abel which fledged in Germany was tracked by satellite to Zambia where many Lesser Spotted Eagles winter. A German Abel wintered North of the Equator in the Sudan and neighbouring countries for over six months and started its return migration on 27 April 2008.
Colour ringing of the Spotted Eagles (Aquila pomarina, Aquila clanga and their hybrids) in Europe - a review
During the years 2000-2008 1377 Spotted Eagles (SE) (Aquila pomarina, Aquila clanga and their hybrids) have been colour ringed in Europe. Out of these, 1303 (94.6 %) were young birds and 74 (5.4 %) were adults. Out of the total, 1290 (93.7 %) were the Aquila pomarina Lesser Spotted Eagles (LSE) - 1229 (95.3 %) young and 61 (4.7 %) adults, 50 (3.6 %) were the Aquila clanga Greater Spotted Eagles (GSE) - 44 (88.0 %) young and 6 (12.0 %) adults and 37 (2.7 %) were the Aquila pomarina x Aquila clanga hybrids (LSE x GSE) - 30 (81.1 %) young and 7 (18.9 %) adults. With respect to the individual European countries the following SE species and numbers were ringed: Slovakia 636 (46.2 %), Poland 333 (24.2 %), Estonia 153 (11.1 %), Germany 116 (8.4 %), Lithuania 68 (4.9 %), Latvia 45 (3.3 %) and Belarus 26 (1.9 %). In the article authors presents a review on Spotted Eagle colour ringing programmes running in individual European countries.
A long-living species like A. heliaca has a natal dispersal period lasting several years. This period is crucial for the survival and conservation of the eagles. In this study we present mortality factors and the survival rate of juvenile and immature A. heliaca from Bulgaria as established by satellite telemetry. A total of 20 juvenile A. heliaca were fitted with GPS/Argos transmitters in their nests in Bulgaria. Fourteen birds were tracked till their death and the bodies were found. Tracking allows the survival rate of juvenile and immature A. heliaca to be estimated for the first time. It is 59.1% for the first calendar year, 83.3% for the second calendar year and 80.0% for the third calendar year. The main mortality factor for juvenile and immature A. heliaca from the Bulgarian population is electrocution, which caused 59.0% of the mortality cases. Other threats identified are shooting, poisoning and collisions. Most of the fatalities of these tracked eagles occurred in Bulgaria (50%) and Turkey (43%). Thus, Turkey is a key country for conservation of the Bulgarian population ofA. heliaca during its dispersal period. Eagles from Bulgaria have been recorded dispersing further south, to Sudan and Saudi Arabia. Conservation efforts are needed both inside and outside Bulgaria in order to reduce mortality. International collaboration and the exchange of experiences should be part of any conservation strategy or plans focused on the eastern imperial eagle.