A Review of accounts of luminosity in Barn Owls Tyto alba

Paper by Fred Silcock 2004-06-04, last updated 2006-06-07

Page 5 of 6

Acknowledgements

I thank the following people for providing comments and information related to the subject of bioluminescence: B. Bartlett, Dr P. J. Herring, Prof. J. Lee, Dr M. McDonald, Dr T. May, Dr O. Parkinson, and W Stanhope.

Thanks to Leslie Attard, Kate Hill, and Jeff & Debbie Keniry for their invaluable help in seeking out important literature.

Thanks to Tom Garnett whose advice helped greatly in setting the research upon its present course. Thanks also to Ron Fink who assisted so much in getting the ball rolling, and Nick Mooney who opened a door. Michael Walters and Dr Robert Prys-Jones (Natural History Museum, Tring) kindly elucidated the Barn Owl's early nomenclature and otherwise assisted with information.

My very special thanks to Stephen Debus for his encouragement, advice, editorial assistance and reading of the paper to the Conference. Mrs Susie Debus expertly re-typed the manuscript onto computer disk. Not least, thanks to Albert Golden. Mark Holdsworth and two anonymous referees commented helpfully on a draft.

References

Allan, J., 1860 (reprinted 1970). Historical notes. Journal of the Quirindi & District Historical Society 2(1): 11.

Andriessen, E.H., 1987. Meat Inspection and Veterinary Public Health in Australia. Rigby, Sydney.

Anon. [= 'A Country Teacher'], 1907. Letter to the editor. The Times (London) 26.12.1907.

Anon. [= W.R.], 1908. The luminous owl. Letter to the editor, Eastern Daily Press (Norfolk) 3.1.1908.

Bunn, D.S., Warburton, A.B. & Wilson, R.D.S., 1982. The Barn Owl. Poyser, Calton.

Clarke, D., 1990. Lights in the sky. Country Life Magazine 19 April: 188 - 189.

Corliss, W.R., 1981. Incredible Life: A Handbook of Biological Mysteries. Bowker, Glen Arm (Maryland, USA).

Dobbs, M.E., 1911. Luminous owls. Irish Naturalist 20:124-126.

Dumbacher, J.P., Beehler, B.M., Spande, T.E, Garraffo, H.M. & Daly, J.W., 1992. Homo-batrachotoxin in the genus Pitohui: chemical defense in birds? Science 258:799-801.

Fleay, D., 1968. Nightwatchmen of Bush and Plain. Jacaranda Press, Brisbane.

Gurney, J.H., 1908. Ornithological report for Norfolk (1907). The Zoologist 12 (series 4):122-136.

Harvey, E.N., 1920. The Nature of Animal Light. Lippincott, Philadelphia & London.

Hollands, D., 1991. Birds of the Night. Reed, Sydney.

Jamieson, B.G.M. & Wampler, J.E., 1979. Bioluminescent Australian earthworms. II. Taxonomy and preliminary report of bioluminescence in the genera Spenceriella, Fletcherodrilus and Pontodrilus (Megascolecidae: Oligochaeta). Australian Journal of Zoology 27: 634-640.

Kozicka, M., 1994. The Mystery of the Min Min Light. Privately published, Mt Molloy, Queensland.

McAlpine, D., 1901. Phosphorescent fungi in Australia. Proceedings of the Linnean Society of New South Wales 25(4): 548-558.

McAtee, W.L., 1947. Luminosity in birds. American Midland Naturalist 38:207-215.

Macnamara, N., 1989. From Clancy's Day to Mine. ABC Enterprises, Sydney.

Moffatt, C.B., 1911. Luminous owls. Irish Naturalist 20: 127-128.

Pigott, T.D., 1908. Luminous owls and the `Will o' the Wisp'. Contemporary Review 84:64-72.

Purdy, R.J.W., 1908. The occasional luminosity of the White Owl (Strix flammea). Transactions of the Norfolk Naturalists Society 8 (4): 547-552.

Roth, W.D. & Gans, C., 1960. The luminous organs of Proctoporus (Sauna, Reptilia) - a re-evaluation. Breviora (Museum of Comparative Zoology) 125.

Rule, A., 1991. Thanks for the Memories. Floradale Productions, Kilmore (Vie.).

Taylor, I., 1994. Barn Owls: Predator-Prey Relationships and Conservation. Cambridge University Press, Cambridge.

Toms, M., 1996. The Lantern Man. Project Barn Owl Newsletter 1: 2-3 (BTOIHawk & Owl
Trust, UK).

Wannan, B., 1970. Australian Folklore. Lansdowne, Melbourne.

Warner, J.A. & Case, J.E, 1980. The zoogeography and dietary induction of bioluminescence in the Midshipman Fish, Porichthys notatus. Biological Bulletin 159: 231-246.

Postscript

In question time, following presentation of the paper, a comment from the floor cautioned against being too dismissive of other explanations for luminescing Barn Owls. It was suggested that intrinsic bioluminescence might be the least likely explanation for the phenomenon, and that perhaps other factors should be considered, such as greater moisture levels in the environment during autumn and winter in which fungi could flourish, e.g. in tree hollows; or perhaps a seasonal emergence of fireflies that Barn Owls consume and so acquire secondary luminescence. Therefore, before time and resources are expended on the suggested laboratory tests for photophores and luciferin in Barn Owl bodies, which may prove negative, better documentation of the phenomenon in the field, by ornithologists, is required. There is scope for use of modern technology, such as video cameras, to be employed.
Another comment raised the possibility of luminescence in other Tyto species.

Author's responses

Fungus: the possibility of fungus as a cause of avian luminosity, regardless of prevailing seasonal or weather conditions, has been addressed in this paper, and for the reasons given seems to offer the least promise as an explanation or fruitful avenue of research.
Fireflies: secondary luminescence as a result of Barn Owls eating fireflies seems, for anatomical reasons, an unlikely possibility. Also, the distribution of the Min Min Light, so often a phenomenon of open, arid country, does not coincide with the limited distribution of Lampyridae. Fireflies are found usually in damp shaded places such as forests and caves, habitats unlikely to used for hunting by Barn Owls. The Sturt's Stony and Strzelecki Deserts, and the fringes of the Simpson Desert, for example, are not likely to be inhabited by fireflies.
Priorities: documentation by ornithologists, in the field and using all available technology, would be a worthwhile exercise and should complement laboratory research. Wild Barn Owls may luminesce rarely. As Barn Owls and Min Mins are not accommodating to observers, expenditure of time and resources in the field may also be
unrewarding. At the time of going to press, laboratory research on Barn Owl bodies is proceeding in a voluntary capacity.
Other Tyto: the phenomenon would seem unlikely in dark-plumaged, forest-dwelling species. Perhaps it might also occur in the Grass Owl Tyto capensis, but so far all the indications point to the Barn Owl.

The Author has published a detailed book on this subject. Click here for more information.

Prev | Next