For the most part, crows come in the same general size, shape and color, but every once in a while individuals will deviate from this template in eye catching ways. These deviations can manifest as missing or elongated beaks, color abnormalities such as white plumage, or jarring metamorphoses into rudderless, flying orbs.
Tailless crows are fairly uncommon; in a typical year I’ll maybe spot a couple afflicted individuals. Although feather loss and replacement is a normal part of a crow’s annual cycle, crows don’t shed their tail feathers simultaneously so we can’t blame molting season for this odd appearance. Instead, a tailless crows most often indicates that the bird recently escaped a predator or other kind of threat.
Similar to some lizards, many bird species can drop their tails defensively as a last resort to avoid being injured or killed. In fact, tail feathers require less force to detach in contrast to other feathers on a bird’s body. In addition, the force required to remove tail feathers decreases with how vulnerable a species is to predation.1 Tail feathers can also be broken, rather than completely lost. Although that might sound painful, unlike a bird’s beak which is full of nerve endings, mature feathers are dead structures like hair or fingernails. While a bird surely feels and avoids the sensation, it’s not painful.
Tails are crucial to most birds not only for their visual appeal but also because they allow birds to steer and maneuver in flight. Without one a crow can still fly and land, but they’re not nearly as agile in the air and you’ll notice their take offs and landings are a bit awkward. Fortunately, the tail will eventually grow back though just how quickly is contingent on what happened to the feathers themselves. If the feathers were pulled out, so long as the follicles weren’t damaged they will begin to regrow immediately. If, on the other hand, the feathers were broken rather than pulled out, the crow will need to wait until its annual summer molt to replace them.
For crows fortunate enough to be brought into a wildlife care facilities, there’s also a secret second option to correcting a broken flight feather: imping. Although little known outside of rehab or falconry circles, imping is an age-old technique dating back to at least the 1240’s when it was mentioned in The Art of Falconry by the Holy Roman Emperor, Frederick II. The procedure involves trimming the broken feather to about one inch above the skin and then inserting a thin piece of wire, fiberglass, or wood (called the imping needle) into the empty feather shaft. A matching donor feather is then affixed to the exposed portion of the imping needle. Picture sheathing a double sided samurai sword, where the sword is the imping needing and the sheaths are the imbedded, trimmed feather shaft and the donor feather respectively. Historically, rust was used as a bonding agent but today vet safe epoxies are the standard adhesive.
So the next time you see a tailless crow go ahead and give it a few extra treats. It’s not in any pain, but it’s been through something fierce. And to quite literally add insult to injury, it looks absolutely ridiculous.
Literature cited
- Moller, A.P., Nielsen, J.T., Erritzoe, J. (2006). Losing the last feather: feather loss as an antipredator adaptation in birds. Behavioral Ecology 17: 1046-1056
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