Bobcats do not possess long, full tails like many other cat species. The bobcat, scientifically known as Lynx rufus, is named for its defining physical feature: a truncated, or “bobbed,” tail. The tail typically measures between 9 to 20 centimeters (about 3.5 to 7.9 inches) in length, which is significantly shorter than the tail of a domestic cat or a cougar. This naturally short tail is a fixed trait of the species, determined by its skeletal structure and genetics.
The Genetic Basis for a Shortened Tail
The short tail is an inherited trait of the Lynx genus. The anatomical reason for the bobbed appearance is a reduction in the number of caudal vertebrae, the bones that make up the tail. A typical long-tailed cat has between 18 and 23 caudal vertebrae, but the bobcat’s tail contains far fewer bones, resulting in the stubby length.
The short-tail characteristic is often associated with a dominant mutation in the Brachyury gene, which influences the development of the vertebral column. This genetic trait is expressed consistently across the population, ensuring the short tail is passed down.
The consistent short tail provides several theorized advantages in the bobcat’s varied habitats. A shorter tail requires less energy to maintain and move, which may contribute to energy conservation during hunting. In colder northern environments, a smaller appendage reduces the surface area exposed to the cold, potentially minimizing heat loss.
Differentiating the Bobcat’s Tail from Related Felines
The question of a long-tailed bobcat often arises from confusion with other wild cats, particularly the cougar and the Canadian Lynx. The Cougar (Puma concolor) possesses a long, thick tail that can measure two to three feet in length. The cougar’s tail is nearly two-thirds the length of its body and is used as a substantial counter-balance for agility and speed.
The bobcat’s tail, in contrast, is characteristically marked with dark bars or spots and has a black tip with a small tuft of white hair on the underside. Its closest relative, the Canadian Lynx (Lynx canadensis), also has a bobbed tail. The lynx’s tail tends to be uniformly black at the tip with less pronounced banding or spotting. The bobcat’s tail is also proportionally longer relative to its body size than that of the Canadian Lynx.
The distinction between the two Lynx species is subtle and relies on careful observation of tail markings and length proportion. However, the difference between the bobcat’s short, marked tail and the cougar’s long, flowing tail is unmistakable.
When Misidentification or Anomalies Occur
The possibility of rare exceptions or misidentification is the most common source of confusion. The typical bobcat tail length of 9 to 20 centimeters represents a natural range of expression for the bobbed-tail gene. In rare instances, a partial expression of the gene or an isolated genetic mutation may result in a bobcat with a tail slightly longer than the average.
These slightly longer tails, sometimes reported up to 8 or 9 inches, are still significantly shorter than a full-sized cat tail and remain truncated relative to the animal’s body length. Such an anomaly is not the same as a bobcat having a long, full, counter-balancing tail like a cougar.
Misidentification is a far more likely explanation for alleged sightings of long-tailed bobcats. A juvenile cougar, which has a long tail but is closer in size to an adult bobcat, is often mistaken for the smaller cat. Conversely, long-tailed domestic cats or juvenile cougars that have suffered an injury or amputation to their tail may be misidentified as a bobcat. In these cases, the observer is seeing a long-tailed animal that is not a bobcat, or a different species that has an acquired short tail.