Predators detect and locate their prey via sensory signals like sight, smell, sound and touch, as well a few uncommon ones.
Predatory animals use different senses like sight, smell, hearing for catching their prey and later feasting on it. But, there are other senses too which predators use for tracking their prey.
Image Source : Mark Mannetti [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
A category of venomous snakes known as pit vipers (Crotaline) are not named because they inhabit pits. They are known for their heat sensing pits near their nose for detecting warmth emitted by warm blooded prey. This hunting technique becomes useful when these snakes hunt in dark. So, no bird or mammal prey will get away when they are close to these hungry serpents.
Image source : Air wolfhound from Hertfordshire, UK [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)]
We used to read stories and we know that foxes are cunning creatures. In real life, they are cunning mainly because of their hunting strategy. Red foxes(Vulpes Vulpes), a common species of fox, is a brilliant hunter of small animals which are under snow or long grass. As scientists were baffled by its behavior, they believe that these foxes might be making use of a magnetic field. When these creatures track a prey which is underneath thick snow, the fox aligns itself with the Earth’s magnetic field i.e. along the axis of the North East direction. It knows exactly where its meal is. Then, it cunningly dives into the snow emerging with a prey in its mouth.
Image source : Olga Ernst [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]
We often wonder how sharks track their prey underwater. The answer lies in the cells of their noses which contain electro receptors which collect the signals emitted by its prey. When an animal like fish or seal contracts, electricity waves are produced underwater. These waves are detected by the cells in shark’s nose. It’s meal time.
Image source : dizfunkshinal [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]
The best known predatory sense for some creatures is by their own vocalizations. They use this procedure known as echo-location, i.e. locating objects using sound. Bats are one of the best known animals for using this procedure. Their stapedius (middle ear muscle) separates the three bones in middle ear avoiding the animal to be temporary deafened by the intensity of their own calls which can be as loud as around 120 db. Toothed whales (odontocetes) which also include dolphins, are the other animals known for using this technique.