Dietary overlap of co-occurring Barn Owl Tyto alba Scopoli and Spoted eagle Owl Bubo africanus Temnick in urban and rural environments

• Autorzy: Kopij G. , Symes C. T. , Bruyns R.
• Języki publikacji: EN

Abstrakty

EN

Diet of co-occurring Barn Owl and Spotted Eagle Owl has been studied by means of pellet contents analysis in urban and rural environments in the Highveld of South Africa. In urban environment, diet of both owl species was dominated by murid rodents (mainly Otomys, Mastomys and Rhabdomys). In rural environment, Barn Owl diet was also dominated by murid rodents, but in the diet of the Spotted Eagle Owl higher proportion of birds and non-murid rodents was recorded. Although in the rural environment the breadth of diet niche was wider in Spotted Eagle Owl (DB = 35.41) than in Barn Owl (DB = 12.67), there was almost total dietary overlap (DO = 0.98) between these two co-occurring owl species. For contrast, there was only slight food niche overlap (DO = 0.12) between these owl species co-occurring in the urban environment, but the diet breadth here was also wider in Spotted Eagle Owl (DB = 29.02) than in Barn Owl (DB = 17.90). In the urban environment diet breadth of the Spotted Eagle Owl is, therefore, slightly wider than in rural environment, while in the case of the Barn Owl the reverse is true. Probably there is lower abundance of available prey in urban and rural areas in the Highveld, in comparison with more natural habitats. This may force both species to resort to a more diverse diet to meet their energy requirements. Both species show, therefore, high plasticity of foraging.

Słowa kluczowe

EN

dietary overlap; Barn Owl; Tyto alba; Spotted Eagle Owl; Bubo africanus; diet composition; rural environment; urban environment; South Africa

• Wydawca: -
• Czasopismo: Polish Journal of Ecology
• Rocznik: 2014
• Tom: 62
• Numer: 4
• Opis fizyczny: p.801-805,ref.

Twórcy

autor

Kopij G.

• Department of Wildlife Management, University of Namibia, Private Bag 1096 Katima Mulilo, Winela Rd., Namibia

autor

Symes C. T.

• School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa

autor

Bruyns R.

• School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa

Bibliografia

• Acocks J.P.H. 1975 - Veld types of South Africa - Mem. Bot. Surv. S.A. 40: 1-128.
• Avenant N.L. 2007 - Barn Owl pellets: a useful tool for monitoring small mammal communities? - Bel. J. Zool. 135: 39-43.
• Berry M.E., Bock C.E., Haire S.L. 1998 - Abundance of diurnal raptors on open space grasslands in an urbanized landscape - Condor, 100: 601-608.
• Cavia R., Cuetoa G.R., Suárez O.V. 2009 - Changes in rodent communities according to the landscape structure in an urban ecosystem – Landsc. Urban Plan. 90: 11-19.
• Dean W.R.J. 1973 - The ecology of owls at Barberspan, Transvaal (In: Proc. Symp. Afr. Pred. Birds, Ed: A.C. Kemp) - Pretoria, Northern Transvaal Orn. Soc. pp. 25-45.
• De Graaf R.M., Geis A.D., Healy P.A. 1991 - Bird population and habitat surveys in urban areas – Landsc. Urban Plan. 21: 181-188.
• Dixon J.E.W., Perrin M.R. 1994 - Prey selection by owls at Etosha, Namibia - J. Orn. 135: 172.
• Grzędzicka E., Kus K., Nabielec J. 2013 - The effect urbanizationon the diet composition of the Tawny Owl (Strix aluco L.) - Pol. J. Ecol. 61: 391-400.
• Hockey P.A.R., Dean W.R.J., Ryan P.G., Maree S. 2005 - Roberts’ birds of southern Africa. 7th ed. - John Voelcker Bird Book Fund, Cape Town, 1296 pp.
• Kopij G. 1997 - Food of the Barn Owl Tyto alba in a farmland near Bloemfontein, South Africa - J. Afr. Raptor Biol. 12: 20-23.
• Kopij G. 2004 - Winter diet of the Barn Owl Tyto alba in Roma, Lesotho - Gabar, 15: 5-9.
• Kopij G. 2006 - The structure of assemblages and dietary relationships in birds of South African grasslands - Wydawnictwo AR we Wrocławiu, Wrocław, 126 pp.
• Kopij G. 2013 - Food niche overlap in co-existing Barn Owl Tyto alba (Scopoli 1769) and Great Horned Owl Bubo virginianus Gmelin 1788 in intensively used farmland - Pol. J. Ecol. 61: 179-181.
• Mendelsohn J.M. 1989 - Habitat preferences, population size, food and breeding of six owl species in the Springbok Flats, South Africa - Ostrich, 60: 183-190.
• Meyer S. 2008 - The Barn Owl as a control agent for rat populations in semi-urban habitats - M.Sc thesis, Faculty of Science, University of the Witwatersrand, Johannesburg.
• Olkowski W., Olkowski H., Van Den Bosch, R., Hom R. 1976 - Ecosystem Management: A framework for urban pest control – BioScience, 26: 384-389.
• Panka E. 1976 – Comparative ecology of twelve species of nocturnal lizards (Gekkonidae) in the Western Australian desert - Copeia, 1976: 125-142.
• Riegert J., Sedlacek O., Hutterer R. 2007 - Diet of sympatric African Grass Owl (Tyto capensis) and Spotted Eagle Owl (Bubo africanus) in the Bamenda Highlands, NW Cameroon - Afr. J. Ecol. 46: 428-431.
• Schneider M.F., Jorge A.A. 2007 - Prey selection of the Barn Owl and the Spotted Eagle-owl in human-degraded and natural environments in southern Mozambique – Ostrich, 78: 655-657.
• Skinner J.D., Smithers R.H. N.1990 - The Mammals of the Southern African Subregion - University of Pretoria, Pretoria, 769 pp.
• Symes C.T., Kruger, T.L. 2012 - The persistence of an apex avian predator, Verreauxs’ Eagle Aquila verreauxii, in a rapidly urbanizing environment - S. Afr. J. Wildl. Res. 42: 45-53.
• Tilson L.R., Le Roux P. 1983 - Resource partitioning in coexisting Namib Desert owls, Bubo africanus and Tyto alba - Madoqua, 13: 221-227.
• Vernon C.J. 1980 - An analysis of owl pellets collected in southern Africa – Ostrich, 43: 109-124.
• Vernon C.J. 1980 - Prey of six species of owl at the Zimbabwe Ruins – 1970–1975 - Honeyguide, 101: 26-28.