Chris Farman recently sent a series of photographs of birds visiting his garden near Dormston. Amongst the photos were two different Blue Tits with grossly distorted beaks (01, 02) and a comment that said they had been visiting the garden regularly. I had not seen anything quite like these before so I thought I would see what I could find out. With two birds being affected I wondered if they were siblings and if it was genetic. Alternatively, was it something the parents had fed to the birds when they were young? I was informed that bird-ringers occasionally report such beaks (Harry Green pers. comm.) so I turned to the internet for more information. I found that such beaks have been noted in various species and in many countries but was still non-the-wiser about what caused the deformation.
I gave the matter little more thought until a further email reached me on 22nd March with the message that the Blue Tits were no longer visiting but a Wood Pigeon with a distorted beak was now present (03). A further internet search took me to the British Trust for Ornithology's web site and a page dedicated to “Big Garden Beak Watch”. The page states that “A number of probable reasons for beak deformities have been suggested, but in many cases exact causes are unknown in the UK and Ireland”. BTO are asking for records and it would be interesting to know if there are any hot spots in Worcestershire. So if you have a bird with a mega-beak coming to your garden send me a photo and details (and don't forget to let BTO know) so we can see which species are affected and in which areas of the county. (Send images to firstname.lastname@example.org)
Big Garden Beak Watch, British Trust for Ornithology (BTO) web site. http://www.bto.org/volunteer-surveys/gbw/about/background/projects/bgbw. [Accessed 27.03.2015].
01. Blue Tit with elongated up turned and curved lower mandible. Chris Farman.
02. Blue Tit head showing elongated upper mandible. Chris Farman.
03. Wood Pigeon with deformed bill. Chris Farman.