Why striped marlin change colour when hunting

It has long been known that striped marlin (Kajikia audax) can “light up” their skin, making their stripes appear much brighter. But why do they do it? Past suggestions include everything from reflecting their mood to confusing their prey. Now, after studying drone footage of hunting blue marlin, Alicia Burns of Humboldt University in Berlin and her colleagues have concluded that the main reason for the colour change is to warn off other marlin during hunts. The footage demonstrates that as one fish moves in to attack, its stripes get brighter and other marlin keep their distance. After an attack, an individual’s stripes dim as it moves away, and then another marlin takes its turn to attack. This behaviour may reduce the risk of the predators colliding with each other, the team conclude. The findings have been published in Current Biology. DOI: – Subscribe ➤ Get more from New Scientist: Official