Have you ever noticed how bobcats move through their habitat? Its a slow, steady, halting sort of pace. In contrast to some predators like coyotes or foxes, who move quite rapidly through their terrain, cats seem to be taking their own sweet time. So you might ask, are cats slow? Lazy? Or just cautious?
One reason for their slow gait has to do with how they detect prey. Cats, and most every other predator, visually detect prey using a system of image formation. That is, they have in their mind an image of what the prey looks like, and as they search through their habitat, they are looking for patterns, shapes, or colors which match the pre-formed image of the prey. It's really no different than what you and I do when we go deer hunting, for example. Successful deer hunters don't go wandering around looking for a broadside image of a mousy-brown deer with large antlers. Rather, experienced deer hunters look for patches of white, subtle movements like the flick of an ear or the twitch of a tail. We have in our mind, an image of what our prey looks like so we go tromping around looking for patterns that correspond with our pre-formed image.
Canines, on the other hand, use image formation less, and their nose much more. Certainly a hungry coyote has in mind what a hiding rabbit looks like, and is seeking a corresponding matching pattern of shape and color. However, canines depend much more on their noses to detect and verify the identity of their prey. Look at the size of a bobcat's eyes in relation to the rest of its body and you can quickly see that while they have a keen sense of smell, their forward-placed eyes are one of their primary detection senses.
In order to combat a cat's method of using image formation to locate prey, the prey animals themselves have evolved to use crypsis to counteract the image formed by a hungry bobcat. Crypsis is a camouflage of any of the sensory indicators (sight, sound, smell, etc)that give away the prey's location or identity. For example, an obvious form of crypsis is a hen pheasant and her drab-brown-dappled plumage. Contrasted to the bright, colorful rooster bird, the hen uses visual crypsis to hide from a hungry cat. Not to be outdone, bobcats (and other predators) are always "adjusting" their image formation to account for these variations. In effect, its always an "arms race" between predators and prey as the prey animals use varying camouflage techniques to avoid predators, and predators have to sharpen their detection skills.
One way a bobcat seeks to overcome crypsis is by altering its search rate. That is, it slows down its gait, allowing it to more thoroughly search for the image patterns of the prey it seeks. Several studies have discussed how altering the search rate by predators enhances not only the predator's ability to visually locate its prey, but it also counteracts the prey's attempted camouflage by allowing the predator to sort of "pick apart" the landscape rather than gloss over a jumbled set of images. Contrast the bobcat's hunting style with a coyote for example. The cat works slowly, carefully placing its feet so as not to alert a potential prey animal that it is near. The coyote, on the other hand, works quickly, steadily, almost like a land-based shark always in motion to constantly sense the air for the smell of its next meal. Once prey is detected, the coyote usually rushes its prey, while the cat sneaks as close as possible before making one short dash to seize its meal.
What does it all have to do with trapping? Well, a number of things but one obvious conclusion would be to use visual objects that correspond to the image formed by your intended target animal. For example, I know a successful -- and outside-the-box thinker -- bobcat trapper who uses full color, life-size cottontail silhouettes at some of his bobcat sets. They are set up under a bush in a natural location for a bunny to hide, and then he uses trail sets to catch the cats as they hunt the faux bunny. There has been much debate over the types of visual attractors that work best on bobcats. Everyone has their favorite. However, those visual objects that correspond to a bobcat's image formation patterns would seem to work the best. It may be as simple as small tufts of polyfil used to represent small bits of fur, or a brown piece of faux fur with a string for a tail to mimic a mouse. Reid Aiton of California used to sell a faux fur "critter" with big doll eyes for use in cage trapping. Those big doll eyes were the same shape and color as a jackrabbit's eyes and I'm sure many a bobcat met his fate because his image formation of a rabbit corresponded to Reid's deceptive critter eyes.
Conversely, some visual attractors like aluminum foil balls, CD's, and other objects may work from time to time to attract a cat, but they do little to resemble a prey animal or another bobcat. Do they work? Sure! Why? Again, scientist hypothesize that cats investigate these unusual objects for two reasons. One reason for closer inspection is due to the cat's near-sightedness. The cat simply has to get closer to determine with visual acuity what the object really is. Second, remember that arms race analogy I made at the beginning of this piece? Well, cats are always on the lookout for prey animals/birds trying to fool their eyesight by masquerading in some form other than the common image formation typically used by the cat. As a result, almost any strange object bears closer inspection to avoid being fooled by a clever camouflage tactic. However, once a cat gets close enough to determine that the object is not food or companionship, it generally loses interest rather quickly.
Good luck on the bobcat trapline!
Edited by Lazarus (09/13/18 11:38 AM)