It can be distressing to see a bird hobbling on one leg, whether the other leg is completely missing or only the foot is amputated. Understanding these injuries, however, can help birders accept how birds react and take steps to prevent unnecessary disabilities.
How Birds Lose Their Legs
There are different ways birds can have a foot or leg amputated. Depending on the extent of the injury it isn't always possible to tell how the bird was disabled, but common causes include…
- Tangling: When thread, fishing line, wire or a similar thin, durable string is tightened around a bird's leg, it will eventually cut off circulation to the limb and cause amputation. This is particularly true if the thread is tightened so far that it is cutting into the leg, or if the bird is young and still growing. Many tangles occur in the nest, when hatchlings get wrapped in unsafe nesting material.
- Predators: A hunting predator may surprise a bird, and as the bird takes flight, the predator may be able to catch hold of a leg. Depending on the type of predator and the strength of their grip, the leg may be broken or bitten off right away, or it may be twisted or torn off in the course of struggling as the bird escapes.
- Deformities: Some birds are naturally hatched with bad legs, due to deformities inside the egg. Many of these young birds will not survive to leave the nest or learn to forage effectively with the disability. If the initial deformity is not severe, however, they may mature but be handicapped with a bad or missing leg.
- Injuries: On rare occasions, birds may suffer unusual injuries that can lead to leg amputation. If the leg is caught in something – wedged in a niche, snapped in a rodent trap, stuck to a glue trap, etc. – the bird may struggle and free itself, but with a grievous injury that leads to the leg tissue dying and eventually falling off. Despite the severity of the injury, the bird may be able to recover and adapt to its new handicap.
Is That Leg Really Gone?
Before assuming a one-legged bird really is an amputee, it is important to know that birds can often appear to have lost a leg without really missing any limbs. Many birds tuck one leg into their plumage to warm it up on cool days, or else to keep it off a hot surface in the summer. This is a common form of temperature regulation, and any birds – flamingos, ducks, geese, raptors, shorebirds, songbirds – may seem to be missing a leg now and then. Birders can watch carefully, however, and will notice that the birds will switch legs periodically, shifting their balance to the other leg.
To truly note whether a bird has one leg, watch for movement. A one-legged bird will hop, or may bounce on its abdomen. It may have more difficulty landing or perching, or may seem to dip or weave as if unbalanced, without putting down that missing leg to correct itself. Right after takeoff, when most birds dangle their legs as they gain altitude, a one-legged bird will, of course, show only one leg.
When a Bird Loses a Leg
Many times when a bird is horribly injured or disabled it will not survive. Other consequences of the injury, such as weakness or infection, may take a toll as well, but there are times when birds adapt amazingly well to being one-legged. Birds do not suffer the psychological trauma of a lost limb as humans would, but instead adapt their behavior to compensate for the missing leg.
Life is more challenging for a bird with one leg. These birds often lose their mates or have more difficulty finding a mate, particularly if the species' courtship displays require two healthy legs. If the bird needs two legs to forage – such as a double-footed scratch in leaf litter or using two sets of talons to capture prey – they must either adapt quickly or they will succumb to starvation. One-legged birds are more vulnerable to predators, and their lifespans are typically shorter than uninjured birds.
Birds that adapt most readily to losing a leg are generally omnivores that can take advantage of multiple food sources. They may not migrate and not have to deal with the stresses of migration. Birds in urban or suburban habitats may adapt even more easily because of the availability of feeders and bird-friendly backyards that provide ample resources.
Helping Disabled Birds and Minimizing Disabilities
A birder's first instinct may be to catch a disabled bird and take it to a rescue or rehabber, hoping it can be helped. Unless a bird still has open wounds or is obviously struggling, however, attempting to rescue a one-legged bird will only cause the bird additional distress, which could itself be fatal. Instead, if birders notice one-legged birds nearby, it is best to…
- Provide Easily Accessible, Nutritious Food: Because one-legged birds have more difficulty foraging, providing a healthy diet in an accessible feeder will give these birds more opportunities to feed. Wide platform feeders or hoppers are best, as birds cannot balance on narrow perches very easily. Positioning these feeders away from busier feeding areas will help disabled birds avoid bully birds more easily as well.
- Provide Abundant Shelter: Because handicapped birds are more vulnerable to predators, they will need safe, secure shelter near any feeding area. A sturdy brush pile or coniferous plantings are useful options. Backyard birders should opt for landscaping to discourage cats and take other steps to discourage feral cats and other predators in the backyard.
- Keep Feeders and Baths Clean: Because one-legged birds are more likely to visit easy bird feeders and baths more frequently, they are more susceptible to any contamination that may spread diseases. Regular cleaning and disinfecting both feeders and baths will minimize that risk while still giving these birds plenty to eat and drink.
- Provide Safe, Appropriate Nesting Material: Birds use a wide variety of nesting material, and birders who provide bits of string, thread or similar materials should be sure lengths are no longer than 2-3 inches to minimize tangling risk. Never offer dryer lint as nesting material because it may contain long threads, and avoid any plastic strings that will not yield or soften if they are part of accidental tangles.
- Pick Up Fishing Line: Because fishing line is the top source of tangles that can cause amputated limbs or fatal injuries, it should always be discarded appropriately rather than left in the riparian environments so many birds favor. Similar materials, such as kite string or balloon ribbons, should also be kept out of reach of wild birds.
While it can be startling to see a one-legged bird, learning more about these injuries can help birders take steps to provide for disabled birds and minimize the risks of more injuries. Seeing how these birds adapt will strengthen any birder's respect and appreciation for just how resilient birds can be.