Prey detection
Prey detection is the process by which
Evolutionary struggle and prey defenses
Predators are in an
Often behavioral and passive characteristics are combined; for example, a prey animal may look similar to and behave like its hunter's own predator (see mimicry).
Prey detection using different senses
There are a variety of methods used to detect prey. Sensory systems used include the visual system, olfactory system (smell), auditory system (hearing) and the somatosensory system (such as touch). Some predators may use all of these senses in pinpointing their prey, while others may depend mainly or entirely on a single one. Detection methods may also be divided into direct detection of the prey organism itself, and indirect clues, such as the smell of its urine.
Visual
Visual predators may form what is termed a search image of certain prey.
Predators need not locate their host directly:
In experimental settings, animals have demonstrated perceptual switching: visual predator would form a searching image of the most abundant cryptic prey species in their environment; as the species is more predated, its number would decrease and the search image for that species would be less useful to the predator; the predator would then switch to a search image of a prey that became more abundant.[2]
Chemical
For many animals the chemical senses are far more important than vision or hearing. Some specialist predatory beetle(s) can locate their bark beetle prey using the pheromones their targets secrete. Pheromones that are exploited by an enemy like this are called kairomones.[3]
Auditory
Some predators rely mainly on sound cues to detect prey. In nocturnal predators non-visual clues are especially important. The barn owl (Tyto alba) relies on noises made by prey, and can locate prey animals with great precision. Bats have the added capability of echolocation to locate prey like flying insects; they can therefore locate prey even if they make no sound.[4]
Following detection
Once a predator has found its prey it will not always attempt to chase or eat it. Prey have other ways of deterring predators from eating them besides avoiding detection.
Animals living in groups have increased vigilance, and even solitary animals are capable of rapid escape when needed. Even if it does make a capture, its prey may attract competing predators, giving it a chance to escape in the struggle. It may also strike a non-vital organ: some species have deceptive appearances such that one part of their body resembles another, such as insects with false heads. This makes consumption (or fatal wounds) less probable, giving the prey a second chance at escaping.
Predators may have extensive capabilities in finding prey, but even when they are successful in doing so they may not end up with a meal.
See also
References
- ISBN 0-87893-009-4
Notes
- ^ Viitala, J., E. Korpimäki, Polakangas, P., Koivula, M. (1995) Attraction of kestrels to vole scent marks visible in ultraviolet light. Nature 373:423–425
- S2CID 14757135.
- ISBN 0-521-48526-6.
- ^ Moiseff, A. and Haresign, T. (2001) Prey Detection by Bats and Owls. Encyclopedia of Life Sciences. DOI: 10.1038/npg.els.0000096