Camouflage - Dazzle Patterning

Dazzle Patterning

Further information: Military camouflage, Dazzle camouflage, and Ship camouflage

Most forms of camouflage are made ineffective by movement: a deer or grasshopper may be highly cryptic when motionless, but instantly seen when it moves. But one form of 'camouflage' works only when in motion: dazzle patterning.

Dazzle camouflage superficially resembles disruptive patterning, but has a different purpose. It was used on ships during the First World War, not to make vessels hard to see, but to make their speed, size, range and direction difficult to ascertain by eye. Dazzle patterning is therefore arguably (by definition) not camouflage, though it has been called camouflage since the First World War. Non-aligning dazzle patterns may have helped to confuse gunners using optical rangefinders, where two halves of the image had to be aligned by eye to estimate the range to the target ship. However the evidence for its success in naval warfare is mixed. Remarkably, some United States Navy camouflage schemes in World War II attempted to combine disruptive camouflage and dazzle.

Motion dazzle is caused by rapidly-moving bold patterns of contrasting stripes, as when zebras run from a lion. Motion dazzle may degrade predators' ability to estimate the prey's speed and direction accurately, giving the prey an improved chance of escape. Motion dazzle distorts speed perception, and is most effective at high speeds; stripes can also distort perception of size (and so, perceived range to the target). Since dazzle patterns (such as a zebra's stripes) make animals more difficult to locate accurately when moving, but easier to see when stationary, there is an evolutionary trade-off between dazzle and crypsis.

• A ship painted with dazzle camouflage to confuse enemy gunners as to her speed, direction, and range

• The Zebra's bold pattern may momentarily confuse predators, especially when many animals are close together and moving rapidly