top of page

Boilers: Theory of operation and Energy Efficiency المراجل البخارية: نظرية العمل وكفاءة الطاقة

Public·9 members

Breed Book Corax Pdf Download

First confirmed breeding record of Northern Raven Corvus corax in Lebanon for over four decades and recent records in Lebanon of Black-winged Kite Elanus caeruleus, Pin-tailed Sandgrouse Pterocles alchata and Black-bellied Sandgrouse P. orientalis

Breed Book Corax Pdf Download

Download Zip:

Northern Raven Corvus coraxOn 13 April 2012 we observed a Northern Raven leaving one of the rocky cliffs at Qalaat Niha, central Lebanon (Plate 1), flying north, but after 100 m he returned cawing to chase away two Short-toed Eagles Circaetus gallicus that were in courtship, with outstretched necks, near the cliffs. We immediately recognized that the Northern Raven (Plate 2) must be defending its nest or chicks but we were still lacking real proof. A visit to the site on 8 February 2013 revealed the presence of five Northern Ravens (Plate 3). On 9 March 2013, we visited the site at 09.30 h with the hope of seeing the bird again but instead we watched a tribe of hyraxes on nearby sunny rocks. However, before we left at 10.45 h, the Northern Raven appeared with a bundle of fine sticks in its beak flying to the same previously frequented cliff. This observation of the carrying of nesting material confirmed breeding by Northern Raven, the first record of breeding by this species for over 43 years in Lebanon. A Northern Raven was seen, by a group of birdwatching trainees, nesting again (carrying food) at Qalaat Niha on 4 April 2014.

Warne, London.BirdLife International. 2014. Species factsheet: Corvus corax. [Downloaded 06/02/2014]. Jennings, MC. 2010. Atlas of breeding birds of Arabia. Fauna of Arabia 25.Kirwan, GM, RP Martins, G Eken & P Davidson. 1998. A checklist of the birds of Turkey. Sandgrouse, Suppl

Common ravens (Corvus corax) attract attention for their advanced socio-cognitive skills19. Notably, their life as non-breeders appears to be socially challenging: they often form groups during foraging20, 21 and actively recruit others in order to overcome the food defence of territorial breeding pairs22. Even though non-breeding ravens compete heavily with each other for access to food and for keeping their food caches23, 24, outside of feeding events they also play, socialize and roost together25. Individuals thereby engage in various affiliative interactions, which may result in the formation of social bonds, which is advantageous in conflicts26,27,28: bonded birds tend to support each other in fights29, 30, they win more conflicts than non-bonded birds and obtain high dominance status26, 27; bonding partners also engage in forms of post-conflict affiliation31, 32, indicating sophisticated relationship repair and support mechanisms. Captive ravens remember their relationship valence to former group members up to three years after being separated from them33 and they notice dominance reversals among conspecifics within and outside of their social group34.

Long-term monitoring is fundamental in assessing changes in breeding populations in response to environmental changes, including land management, and can provide important insights into ecological processes, although it has some limitations in inferring causality in comparison with experimental approaches. Here, we describe changes in the abundance of four raptor species and Common Raven (Corvus corax), a protected corvid, during a 27-year study on a grouse moor in southwest Scotland, where raptors have not been illegally killed since 1990 (Thirgood and Redpath 2000). In contrast to previous between-moor comparisons, our study enabled us to semiexperimentally test the responses of raptors and Raven to successive periods of grouse moor management, i.e., its cessation, restoration, and further cessation at the same site. First, we examined changes in both numbers and breeding success of two ground-nesting species (Hen Harrier and Merlin [Falco columbarius]) and three tree- or crag-nesting species (Peregrine, Common Buzzard [Buteo buteo], and Raven) in relation to these periodic changes in grouse moor management. We predicted that both breeding success and abundance of ground-nesting raptors would be higher when the moor was actively managed for Red Grouse, with gamekeepers reducing numbers of potential predators, especially foxes. Second, we tested whether changes in the abundance of key prey species (passerines, Red Grouse, and field voles (Microtus agrestis) could have contributed to the observed changes in abundance and breeding success of ground-nesting raptors. We hypothesized that changes in prey abundance would influence brood size at fledging (Newton 1979, Salamolard et al. 2000), while changes in nest predation rates, which often result in the loss of the whole clutch or brood, would influence the proportion of successful breeding attempts.

Predation also represents a higher risk to nests located at the colony edge (Tenaza 1971). Although our study islands do not have terrestrial predators, we documented predation of adult birds by raptors such as Peregrine Falcon (Falco peregrinus) and Goshawk (Accipiter genitilis), of chicks by White-tailed Eagle (Haliaeetus albicilla), Marsh Harrier (Circus aeruginosus), and Kites (Milvus migrans and Milvus milvus), and of eggs by Ravens (Corvus corax) and Crows (Corvus corone cornix). We observed that all these raptors tended to hunt at the edges of the colony, because the communal defense behavior of the breeding birds was much stronger in the center. Therefore, we assume that even in our colonies, predation risk is higher at the edges.

  • bottom of page