Pinker flamingos are more aggressive than their paler counterparts, a new study says

The pinker the flamingo, the more aggressive they are when fighting for food, according to new research published Monday.

In the study, published by the University of Exeter and WWT Slimbridge Wetland Centre, zoologists scored the color of the birds and observed their behaviors as they foraged for food in different-sized situations.

The pink color in flamingos comes from carotenoids, the pigments that the flamingos ingest with their food, which include algae and crustaceans. The pink color symbolizes an “honest signal” which reflects the animal’s health and its ability to forage, according to Dr. Paul Rose, a zoologist and professor with the University of Exeter, who led the study.

“Birds use this pink color during courtship — the pinker the flamingo, the better quality it will be as a mate,” Rose told CNN. “This pink color may also help some [flamingos] gain access to resources, but more research is needed in this last point.”

Flamingos, both male and female, with deeper pink pigmentation are more aggressive as they are healthier and able to better dominate resources over their paler rivals. Other flamingos recognize their strength and give them space.

The study also found that paler flamingos are more relaxed when they are given more space to search for food. When flamingos were held outdoors in larger pools, they exhibited less aggressive behaviors and spent more time foraging.

“This research has important animal welfare implications,” Rose told CNN. “Zoos can make small changes to how they feed their birds to improve the performance of natural behavior. All they need to do is give their flamingos more room to forage in and that improves their foraging patterns and reduces aggression, therefore keeping birds calmer and more relaxed.”

Rose uses this research to find ways to make small changes to how captive flamingos are fed so they can behave more like wild birds and use their time performing behaviors that will lead to better health.

“Wild flamingos spend a large proportion of their day feeding, we can mimic this natural activity easily in the zoo,” Rose said. “This is why I love doing my research at WWT Slimbridge, because they are open to new ideas and were happy to change how the birds were fed to see what may happen to the bird’s activity.”