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These reports are from countries outside North America. I'll be compiled a limited number of these that fit the pattern of very elongated or crossed bills.
If you have any other reports of bill deformities (primarily crossed or overgrown bills) in passerines to report, please contact Julie Craves (jac AT rrbo.org); this page will be periodically updated. Please note that due to the high rate of bill deformities on eastern House Finches (which may be connected with the prevalent conjunctivitus disease or genetic bottlenecking) that House Finch reports will not be included.If you post your photos on the online photo sharing site Flickr, there is a photo pool called Birds with Deformed Bills. You can add your photos of any species of bird with a deformed bill by joining the pool.
This compilation of bill deformities is property of the Rouge River Bird Observatory. Do not use or cite without permission.
Maxilla = top; mandible = bottom
Flycatchers to European Starling
Warblers through House Sparrow, and literature cited
Non-North American reports
Bill tumors, most due to avian pox
| Species | Details | Source |
| Rook (Corvus frugilegus) | Feb 2008; both maxilla and mandible elongated and upcurved; Malahide, Dublin, Ireland | Flickr |
| Jackdaw (Corvus monedula) | Photo dated April 2007; maxilla elongated and strongly hooked; Wales, UK | Flickr |
| Blue Tit (Parus caeruleus) | Great Britain | Andy Mitchell (andy AT witsend.freeserve.co.uk) |
| Blue Tit | Photo dated Jan 2008; maxilla elongated and downcurved; Great Britian | Flickr |
| European Blackbird (Turdus merula) | Great Britain | Andy Mitchell (andy AT witsend.freeserve.co.uk) |
| Nightingale (Luscinia megarhynchos) | Great Britain | Andy Mitchell (andy AT witsend.freeserve.co.uk) |
| Whitethroat (Sylvia communis) | Photo dated April 2004; ;maxilla elongated and crossed; Upper Sheringham, Norfolk, England | Flickr |
| Arrow-marked Babbler (Turdoides jardineii) | Photo dated Sep 2007; crossed; Kruger National Park, South Africa | Flickr |