Alexi is an American flamingo (Phoenicopterus ruber) who hatched at Denver Zoo in 2008. There are 6 species of flamingo and Denver Zoo is home to 2 species: Chilean and American. Alexi’s species, the American flamingo, is from the Caribbean region and lives in saline lagoons and muddy shallow lakes.

You can tell the American Flamingo apart from the Chilean because the Americans are the brightest pink of all the flamingo species. All flamingos get their coloring from the food they eat. They eat food that contains carotenoids such as Canthaxanthin, which colors the feathers and Astaxanthin, which colors the skin and legs. In the wild they would eat invertebrates, mollusks, insects, crustaceans, algae and other plant material. Here at the zoo, Alexi eats a formulated soaked pellet for flamingos and krill for a treat. Flamingos can’t make the color on their own so they will fade to grey or white if they don’t eat foods containing the red pigments. The chicks are born grey or white and get the pink color as they age. Alexi is one of 18 other American flamingos here at the Denver Zoo and there are 75 total with both species.

Alexi has a very special way of eating. She filters her food like some whales. Flamingos hold their head upside down in water and suck in water and food with their piston-like tongue that fits inside the lower beak. The tongue has barbs facing the throat that pulls the food in and the water is pushed out through the lamellae (rows of keratinous plates covered in tiny hairs called cilia) similar to some whales. Sometimes you will see her stamping her feet in the water to flush up more food from the bottom.

When you look at Alexi, you might think that she has a backward facing knee.  What looks like a knee to us is actually the equivalent to her ankle joint. Her knee joint is up high in her feathers and hidden from view. Her upper leg (tibio-tarsus) is the same as the human lower leg. Her lower leg is what we would call the upper foot bones also called the tarsometatarsus in birds. There is also minimal muscle in bird legs below the knee. Instead of muscle they mostly have tendons in their lower legs.

During the winter you can find Alexi in her winter quarters near the How Far Can You Jump sign.  In the summer she can be found in the flamingo pond across from Primate Panorama.  You can tell her apart from the other flamingos with her leg band. It is on her left leg, Green 39.