Meeting Place For People Interested In Corvids
Pododermatitis, commonly known as “bumblefoot”, has become a frequently seen disease in companion and aviary birds. Pododermatitis is a general term for any inflammatory or degenerative condition of the avian foot. Pododermatitis may occur in any avian species, but is particularly problematic in permanently and temporarily captive birds, such as birds of prey, chickens, turkeys, ducks, geese, swans, waders, seabirds as well as canaries, finches, budgerigars and cockatiels.
Most avian species are susceptible to one or more of the avian poxvirus strains and / or species. It has been reported that naturally occurring avian pox infections can affect about 60 species of wild birds, comprising 20 families. Poxviruses can be transmitted in a number of different ways. Even though they are unable to penetrate unbroken skin, small abrasions are sufficient to permit infection. The most common method of transmission is by means of biting insects such as mosquitos, mites, midges or flies. Many biting insects have been shown to be mechanical vectors only, transferring the virus from infected to susceptible birds by contamination of their skin-piercing mouthparts. Transmission can also occur directly by contact between infected and susceptible birds or by contact with contaminated objects, such as bird feeder perches. Aerosol transmission, although rare, can occur from viruses being carried along with dust, particularly in confined situations such as aviaries. At the time of year when vectors are at the highest numbers, avian pox transmission is greatest. 1
We rescued jackdaw Saber as a juvenile bird in June 2014, after we managed to free him from his entanglement in an insufficiently deployed and damaged nylon bird net. We found him hanging head down on his leg whilst his wing was twisted and entangled in the loose strands of the damaged net. Saber must have been trapped in this position for a prolonged period of time, as he was very weak, barely responsive and in shock. Saber suffered severe soft tissue injuries to his left wing, a subluxated hock joint and a paralysis of the left foot caused by nerve damage.
The most common causes in the wild for birds loosing a leg is entanglement with thread, fishing line, balloon ribbons or other litter. This can happen at all ages, even as a nestling. Other causes include predator attacks, birth deformities or injuries caused by traps and snares.
Over the years we have been contacted repeatedly by rescuers and lay people, who were caring for corvids such as magpies, jackdaws and crows, and who observed that their foster birds showed difficulties with flying despite appearing otherwise fit and healthy. Some of these birds demonstrated abnormal flight feathers and showed an unusual or even abnormal behaviour not normally expected in wild birds. A closer assessment of the plumage showed quite quickly that these birds had been wing clipped.
