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 ===== Introduction =====
-Whilst doing a bit of research around this contentious topic, it became quickly apparent that there is no study or paper to find, which conclusively proves that feeding bread to waterfowl is the sole cause for the development of angel wing deformities. Despite this fact, most wildlife and waterfowl experts seem to agree that the overwhelming cause of angel wing is an unhealthily high protein and / or carbohydrate based diet. Unsurprisingly, it was not difficult to find plenty of advice and warnings suggesting not to feed bread to birds, and in particular not to waterfowl. However, with all the advice being provided, no scientific references were given, which would certainly help to clarify and understand the situation.
+{{ :swan.jpeg?200|}}Whilst doing a bit of research around this contentious topic, it became quickly apparent that there is no study or paper to find, which conclusively proves that feeding bread to waterfowl is the sole cause for the development of angel wing deformities. Despite this fact, most wildlife and waterfowl experts seem to agree that the overwhelming cause of angel wing is an unhealthily high protein and / or carbohydrate based diet. Unsurprisingly, it was not difficult to find plenty of advice and warnings suggesting not to feed bread to birds, and in particular not to waterfowl. However, with all the advice being provided, no scientific references were given, which would certainly help to clarify and understand the situation.
 On the other hand, we did find a variety of research, which has been undertaken with the aim to establish possible causes for angel wing deformities. Most of the available literature has been produced by using and abusing domestic birds raised for human food production, or by doing questionable feeding trials with captive raised wild bird species. However, we didn’t find any useful research, which has been undertaken to establish the causes for angel wing deformities at the source, meaning in the wild. In this context, please note that the list of research reviewed and used for this blog post is not meant to be exhaustive.
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 Disease transmission is better facilitated under dense population conditions. Habituation of swans, geese and ducks being fed in parks potentially creates further conflict, if for example large geese or swans are defending a nesting female or a brood of goslings or cygnets. Also, supplemental feeding of migrant birds can interfere with normal migration patterns by delaying departure or suspending the behaviour altogether.
 The best solution for waterfowl problems situated around public parks is to minimise uncontrolled excessive supplemental feeding. Feeding a balanced diet will decrease the likelihood of nutritional disorders to occur. However, feeding a balanced diet will not prevent overcrowding, disease concerns, habitat degradation, habituation or the risks associated with premature breeding attempts or delayed migration.
-Bibliography
-Kreeger, T.J. & Walser, M.M., Carpometacarpal deformity in giant Canada geese (Branta canadensis maxima Delacour), 1984, volume 20, pages 245-248
-Kreeger, T.J. & Walser, M.M., Carpometacarpal deformity in giant Canada geese (Branta canadensis maxima Delacour), 1984, volume 20, pages 245-248.
-Zoological Society of London, London, UK, Kear, J., Notes on the nutrition of young waterfowl, with special reference to slipped-wing, 1973, volume 13, pages 97-100
-Yeisley, C.L., Surgical correction of valgus carpal deformities in waterfowl, Proceedings of the Association of Avian Veterinarians, 1993, pages 161-163
-Zoological Society of London, London, UK, Kear, J., Notes on the nutrition of young waterfowl, with special reference to slipped-wing, 1973, volume 13, pages 97-100
-T.N. Tully, M.P.C. Lawton & G.M. Dorrenstein (Eds.), Butterworth Heinemann, Oxford, UK, 2000, Cranes, Olsen, G.H., pages 215-227
-Tully, T.N. Jr., Dorrestein, G.M., & Jones, A.K., Saunders, Elsevier Limited., 2009, Cranes, Olsen, G.H. , pages 243-257
-Lin, M. J., Chang, S. C., Lin, T. Y., Cheng, Y. S., Lee, Y. P., & Fan, Y. K. (2015). Factors Affecting the Incidence of Angel Wing in White Roman Geese: Stocking Density and Genetic Selection. Asian-Australasian journal of animal sciences, 29(6), 901-7
-Zoological Society of London, London, UK, Kear, J., Notes on the nutrition of young waterfowl, with special reference to slipped-wing, 1973, volume 13, pages 97-100.
-B.W. Ritchie, G.J. Harrison & L.R. Harrison, Wingers Publishing Inc., Lake Worth, Fl., 1994, Anseriformes, Olsen, J.H., pages 1237-1275.
-]D. Brown, ABK Publications, South Tweed Heads, NSW, Australia, 1998
-Serafin, J.A. The influence of diet composition upon growth and development of sandhill cranes, 1982, valume 84, pages 427-434
-Bilateral Valgus Deformity of the Distal Wings (Angel Wing) in a Northern Goshawk (Accipiter gentilis), Petra Zsivanovits, Deborah J. Monks, and Neil A. Forbes, Journal of Avian Medicine and Surgery 2006 20 (1), 21-26
-L. Pitman, Robert & Ballance, Lisa & Bost, Charles. (2012). Incidence of Wing Deformities (‘Angel Wing’) Among Masked Boobies at Clipperton Island: Life History Consequences and Insight into Etiology. The Wilson Journal of Ornithology. 124. 597-602. 10.2307/23324568
-Helen M. Thompson, Alwyn Fernandes, Martin Rose, Shaun White, Adrian Blackburn, Possible chemical causes of skeletal deformities in grey heron nestlings (Ardea cinerea) in North Nottinghamshire, UK, Chemosphere, volume 65, Issue 3, 2006, pages 400-409
-Reed, D. H. (2004), Extinction risk in fragmented habitats. Animal Conservation, 7: 181-191. doi:10.1017/S1367943004001313