Explanation
Shrimp can contribute, but this is an incomplete explanation for flamingos as a group. Their pink and reddish colors come from carotenoid pigments obtained through food, including algae and small crustaceans such as brine shrimp.
The Smithsonian explains that brine shrimp consume microscopic algae containing these pigments. Flamingos obtain and metabolize carotenoids when they eat algae or the shrimp. San Diego Zoo independently identifies algae and crustaceans as dietary sources of the birds' coloration.
Diet differs between species: some flamingos filter very fine foods such as algae, while others eat more invertebrates. San Diego Zoo also maintains its flamingos' coloration with pigment-containing pellets. Shrimp are therefore one possible route for the pigments, not a necessary explanation for every pink flamingo.
Key takeaway
Flamingos get their pink color from dietary pigments that can come through algae or shrimp.