Lesser flamingos (Phoeniconaias minor), a species of flamingo found in sub-Saharan Africa and India, do not have a breeding season — they breed when they’re in good enough condition; and this is often displayed by a ‘pink flush’ in the feathers. So when the birds squabble over food, the pinkest individuals tend to push the others around, according to new research.
A bright pink lesser flamingo shoving a paler bird. Image credit: Paul Rose.
“Flamingos live in large groups with complex social structures. Color plays an important role in this,” said Dr. Paul Rose, a researcher at the University of Exeter.
“The color comes from carotenoids in their food, which for lesser flamingos is mostly algae that they filter from the water.”
“A healthy flamingo that is an efficient feeder — demonstrated by its colorful feathers — will have more time and energy to be aggressive and dominant when feeding.”
Dr. Rose and his colleague, Laura Soole of University Centre Sparsholt, studied the behavior of lesser flamingos housed at the Wildfowl & Wetlands Trust (WWT) Slimbridge Wetland Centre.
The scientists observed the birds in different feeding situations: at an indoor feeding bowl, a larger indoor feeding pool, and outdoors with food available in a large pool.
In the outdoor pool, the flamingos spent less than half as much time displaying aggression, while foraging time doubled (compared to when fed from a bowl).
“When birds have to crowd together to get their food, they squabble more and therefore spend less time feeding,” Dr. Rose said.
“It’s not always possible to feed these birds outdoors, as lesser flamingos only weigh about 2 kg and are native to Africa, so captive birds in places like the UK would get too cold if they went outside in the winter.”
“However, this study shows they should be fed over as wide an area as possible.”
“Where possible, creating spacious outdoor feeding areas can encourage natural foraging patterns and reduce excess aggression.”
“This research shows that zoos don’t have to make huge changes to how they keep their animals to make a big, beneficial difference to animal behavior.”
The findings were published in the journal Ethology.
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Paul Rose & Laura Soole. What influences aggression and foraging activity in social birds? Measuring individual, group and environmental characteristics. Ethology, published online June 8, 2020; doi: 10.1111/eth.13067
