Clamator glandarius Linnaeus, 1758
Coccystes glandarius (L.): Klain, 1909: 65.
Conservation status: in Bulgaria: Critically endangered CR A[3(b+c)]+B[1(a+b(i)] +D+ E, BDA-III; International: BeC-II.
General distribution. An Ethiopian species. The breeding area embraces Africa, Asia Minor and Europe (Spain, Portugal, Southern France, Italy, the former Yugoslavia, Greece, Bulgaria, Cyprus). Reported in England, Belgium, Germany, Denmark, Sweden, the Netherlands, Albania. The birds breeding in the Palearctic winter in Tropical Africa.
Distribution and abundance in Bulgaria. A breeding summer visitor species. The distribution during the breeding period is directly dependent on the crow birds, mainly the Magpie, on which it parasitizes. Until about 1985, singular birds were rarely observed in the valleys to an altitude of about 600 m. . At present it is found mainly along the valleys of the rivers Struma, Maritsa, in the mountains Eastern Rhodopes, Sakar Planina and in the areas of the cities of Sofia, Stara Zagora and Pleven and the towns of Karnobat and Aytos, cape Kaliakra [2,3,4]. Recently it has been reported in the following habitats: to the north of the town of Elhovo, May 2003 – one adult bird, near the fish farms at Septemvri railway station, May 2003 – two adult birds, near the village of Zvanichevo, Pazardzhik region, May 2004 – one adult bird; near Pyasachnik Reservoir in the vicibity of the village of Belovitsa, May 2005 – one adult bird; near the fish farms of the village of Kovachevo; near the village of Golyamo Krushevo, Burgas region, May 2004 – one bird (A. Ignatov, personal communication); the valley of the Krumovitsa River in the area of Krumovgrad, near the village of Gorna Kula, 25.05.2005 – two adult birds (P. Roberts and M. Dimitrov, personal communication), ibid., 12.05.2006 – one bird (L. Profirov, personal communication). Between the village of Balgarevo and cape Kaliakra, 13.05.2006 – a pair of courting birds (M. Dimitrov, personal communication). The total breeding population in Bulgaria is estimated at 10 –20  and 20-30 breeding pairs .
Habitats.Valley and hilly areas with deciduous forests, agricultural areas and artificial landscapes, orchards, forestation belts, bush vegetation, parks and gardens in urban areas, industrial zones.
Biology. A nest parasite. It lays its eggs in the nests of crow birds, mainly the Magpie, rarely in the nests of Starlings, Hoopoes and Kites. Within one breeding season the female lays in the nests of its hosts up to 12–15 eggs. The incubation continues for 10 – 14 days. Food: large insects and their larvae.
Similar species. The Cuckoo (Cuculus canorus).
Negative factors. Illegal shooting, collecting, treating agricultural and forest cultures with insecticides. Destruction of the nests of the Magpie and other crow birds.
Conservation measures taken. Protected according to the Biological Diversity Act.
Conservation measures needed. Target treatment of agricultural and forest areas with selective insecticides, systematic raising of the ecological culture of the hunters.
References. 1. Nankinov et al. 1997; 2. Nankinov, 1999; 3. Miltschew, 1992; 4. Bedev, 2003; 5. Kostadinova, 1997; 6. Nankinov et al., 2004.
Author: Kiril Bedev