Discover how humbug damselfish use their striking black and white stripes to create a ‘motion dazzle’ effect, confusing predators and helping them evade capture. This groundbreaking research sheds light on the complex anti-predator strategies employed by these resilient coral reef inhabitants.
Camouflage Meets Movement
We are used to the idea of animals camouflaged in dense forests or grasslands, so motionless and invisible that they would escape our eyes. Yet the humbug damselfish defies this paradigm. The small striped coral reef fish are famous for moving often as they feed and find their way about.
Now, new research from Macquarie University shows that the high-contrast patterns of the humbug damselfish sort of act as both: in its resting state, these markings blend seamlessly into coral backgrounds to help escape detection, while in action this colouration causes a ‘motion dazzle’ effect. This way it messes with the tracker of potential predators, which provides incorrect measurements for the piecewise information of damselfish location, speed and direction, making it harder to turn these beautiful fish into dinner.
Adapting to the Environment
Researchers publishing in the journalPeerJ say humbug damselfish are one their most plastic — meaning highly adaptable — behaviors for preventing themselves from being eaten by predators. Unsurprisingly, when placed into the fish’s natural coral reef habitat — where their vertical stripes would be indistinguishable amid intertwining branching corals — they moved toward the background, and also generally reduced movement. This keeps the young safe and hidden from predators.
Yet when the damselfish are feeding outside the coral colony where camouflage is less effective, they move more and use their stripes for another purpose — ‘motion dazzle’. In this way, they generate a visual interference with which to confuse the position and movements of predators, thus also increasing the chances of escape and survival.
Conclusion
The results of this research on humbug damselfish reveal the impressive flexibility and sophistication of their defensive behaviors. Thus, by utilising both camouflage and motion dazzle, these tough coral reef inhabitants have employed a wonderful two-staged strategy for getting away from their predators. While our knowledge of deep-sea conundrums remain obscured in mystery, studies such as this shed light on the complex adaptations that allow marine life to flourish.
