Inheritance of plumage morphs in Little Eagles Hieraaetus morphnoides in northern New South Wales
Candice Larkin, S. J.S. Debus
pp. 124-128
Abstract
Polymorphism and inheritance of plumage colour in the Little Eagle Hieraaetus morphnoides were studied in northern New South Wales, by tallying records of parental morph combinations in breeding pairs and the morphs of their offspring in the 1980s, 2000s and 2017–2019 (n = 41 pair combinations). The average ratio in breeding adults was 4.9 light:1 dark, with dark males outnumbering dark females (1.8:1). Light × light pairs always produced light young (n = 32). Dark male × light female pairs variously produced light and dark offspring of both sexes (n = 12). Light male × dark female pairs produced dark young of either sex (n = 4) and one light young of unknown sex. One dark × dark pair produced a dark young. We conclude a Mendelian inheritance pattern with the dark morph recessive. From a small sample of mixed pairs with a dark male, the ratio of offspring morphs did not differ significantly from that expected by the Hardy–Weinberg equation, but mixed pairs with a light
male produced 4 dark offspring to one light, versus the expected Hard –Weinberg ratio of 1.95 light: 1 dark. This outcome suggests a non-random transmission of the dark allele by heterozygous light males, and a similar pattern of inheritance to that in the related Booted Eagle H. pennatus.
References
Amar, A., Koeslag, A. & Curtis, O. (2013). Genetic plumage polymorphism in a newly colonized Black Sparrowhawk population: Classification, temporal stability and inheritance patterns. Jounal of Zoology 289, 60–67.
Bosch, J. (2019). Clinal polymorphism variation in the Booted Eagle Hieraaetus pennatus: The influence of climate during the breeding season. Bird Study 66, 306–316.
Bosch, J., Calvo, J.F., Martínez, J.E., Baiges, C., Mestre, J. & Jiménez-Franco, M.V. (2020). Evidence of non-random mating in a colour polymorphic raptor, the Booted Eagle. Journal of Ornithology 161, 849–857.
Bosch, J., Mestre, J., Baiges, C., Martínez, J.E., Calvo, J.F. & Jiménez-Franco, M.V. (2019). Colour plumage polymorphism in the Booted Eagle: Inheritance pattern and temporal stability of the morph frequencies. Journal of Zoology 308, 212–220.
Clark, W.S. (2012). The eagle genus Hieraaetus is distinct from Aquila, with comments on the name Ayres’ Eagle. Bulletin of the British Ornithologists’ Club 132, 295–298.
Cupper, J. & Cupper, L. (1981). Hawks in Focus. Jaclin, Mildura, Vic.
Debus, S. (2017). Australasian Eagles and Eagle-like Birds. CSIRO Publishing, Melbourne.
Debus, S.J.S. (1989). Plumages and moult of the Little Eagle. Australian Bird Watcher 13, 103–113.
Debus, S.J.S. (1991). Further notes on territory, breeding and plumage of the Little Eagle. Australian Birds 25, 1–10.
Debus, S.J.S. (2008). Biology and diet of the White-bellied Sea-Eagle Haliaeetus leucogaster breeding in northern inland New South Wales. Australian Field Ornithology 25, 165–193.
Debus, S.J.S. (2011). Parental time-budgets and breeding behaviour of the Little Eagle Hieraaetus morphnoides in northern New South Wales. Corella 35, 65–72.
Debus, S.J.S. & Ley, A.J. (2009). Aspects of the breeding cycle of the Little Eagle Hieraaetus morphnoides. Australian Field Ornithology 27, 76–99.
Ferguson-Lees, J. & Christie, D.A. (2005). Raptors of the World, A Field Guide. Helm, London.
Galeotti, P., Rubolini, D., Dunn, P.O. & Fasola, M. (2003). Colour polymorphism in birds: Causes and functions. Journal of Evolutionary Biology 16, 635–640.
Galván, I., Gangoso, L., Grande, J.M., Negro, J.J.,
Rodríguez, A., Figuerola, J. & Alonso-Alvarez, C. (2010). Antioxidant machinery differs between melanic and light nestlings of two polymorphic raptors. PLoS ONE 5 (10), e13369.
Gjershaug, J.O., Lerner, H.R.L. & Diserud, O.H. (2009). Taxonomy and distribution of the Pygmy Eagle Aquila (Hieraaetus) weiskei (Accipitriformes: Accipitridae). Zootaxa 2326, 24–38.
Hollands, D. (2003). Eagles, Hawks and Falcons of Australia.
2nd edn. Bloomings Books, Melbourne.
Krüger, O., Lindström, J. & Amos, W. (2001). Maladaptive mate choice maintained by heterozygote advantage. Evolution 55, 1207–1214.
Larkin, C., Jenkins, R., McDonald, P.G. & Debus, S.J.S. (2020). Breeding habitat, nest-site characteristics and productivity of the Little Eagle (Hieraaetus morphnoides) near Armidale, New South Wales. Pacific Conservation Biology 26, early online https://doi.org/10.1071/PC19033
Lerner, H., Christidis, L., Gamauf, A., Griffiths, C., Haring, E., Huddleston, C.J., Kabra, S., Kocum, A., Krosby, M, Kvaløy, K., Mindell, D., Rasmussen, P., Røv, N., Wadleigh, R., Wink, M. & Gjershaug, J.O. (2017). Phylogeny and new taxonomy of the booted eagles (Accipitriformes: Aquilinae). Zootaxa 4216, 301–320.
Marchant, S. & Higgins, P.J. (Eds) (1993). Handbook of Australian, New Zealand & Antarctic Birds, Volume 2: Raptors to Lapwings. Oxford University Press, Melbourne.
Martínez, J.E., Calvo, J.F., Jiménez-Franco, M.V., Zuberogoitia, I. & López-López, P. (2016). Colour morph does not predict brood size in the Booted Eagle. Ornis Fennica 93, 130–136.
McDonald, P.G. (2003). Variable plumage and bare part colouration in the Brown Falcon, Falco berigora: The influence of age and sex. Emu 103, 21–28.
Rae, S., Wimpenny, C., Mulvaney, M., Davies, M., Fletcher, D., Roberts, D. & Olsen, P. (2019). Preliminary results from study of Little Eagles in the ACT and nearby NSW in 2018–2019. Canberra Bird Notes 44, 145–151.
Romano, A., Séchaud, R. & Roulin, A.. (2019). Climate-driven convergent evolution of plumage colour in a cosmopolitan bird. Global Ecology and Biogeography 28, 496–507.
Roulin, A. (2004). The evolution, maintenance and adaptive function of genetic colour polymorphism in birds. Biological Reviews 79, 815–848.
Roulin, A. & Wink, M. (2003). Predator-prey relationships and the evolution of colour polymorphism: A comparative analysis in diurnal raptors. Biological Journal of the Linnean Society 81, 565–578.
Roulin, A., Müller, W., Sasvári, L., Dijkstra, C., Ducrest, A.-L.,Riols, C., Wink, M. & Lubjuhn, T. (2004). Extra-pair paternity, testes size and testosterone level in relation to colour polymorphism in the Barn Owl Tyto alba. Journal of Avian Biology 35, 492–500.
Tate, G.J. & Amar, A. (2017). Morph specific foraging behavior by a polymorphic raptor under variable light conditions. Scientific Reports 7, 9161.
Tate, G.J., Bishop, J.M. & Amar, A. (2016). Differential foraging success across a light level spectrum explains the maintenance and spatial structure of colour morphs in a polymorphic bird. Ecology Letters 19, 687–694.