The white and sometimes red ibises of Belize

The bright colours of the scarlet ibis make it one of the most striking birds in the Burgers’ Bush. So bright in fact, that this deep pink bird is primarily mistaken by young children for a flamingo. 

Even pinker than a flamingo?

Its size and beak shape are not really that similar, but it definitely has the same colours! Both flamingos and scarlet ibises owe their colouration to pigments in their food. The tiny shrimp and crabs devoured by both species contain a pigment called canthaxanthine, which is derived from the better-known beta carotene, the pigment that gives carrots and oranges their colour. These pigments accumulate in the skin and feathers of scarlet ibises and flamingos.

Usually white, sometimes red

Although the scarlet ibis has been considered its own species for nearly 250 years since it was first described by the biologist Linnaeus, modern-day biologists have called this status into question. The scarlet ibis shares a highly substantial number of traits with the white ibis. In terms of their skeletons, beaks, and feet, these species appear to be the same. There is also no difference in the arrangement of their feathers.

Red offspring

On the inside, white and scarlet ibises are identical. The only thing that separates them is that dazzling colour! The white ibis has a broader range and often occurs in the mangrove forests of Belize, where it also breeds. In contrast, the scarlet ibis is more common along the northwest coast of South America. However, they do migrate and sometimes fly a bit too far. In any case, occasional vagrant specimens find their way to other areas, including the coast of Belize. Strangely enough, the differently coloured variants also seem to find each other attractive. They regularly mate with each other in both the wild and the zoo, resulting in light, orange-red hybrids. This has led to discussion amongst experts as to whether the scarlet ibis should be considered a true species or as a differently coloured variant of the white ibis.  

Never brown in the Bush

Both the white and scarlet ibises begin their lives with brown feathers. After a phase in which they exhibit an alternating pattern, they finally become the colour of the adult bird at roughly two years of age. However, there will never be a brown scarlet ibis at Burgers’ Bush. As this species is being bred often enough at other zoos and it takes a lot of effort to catch a scarlet ibis in such a large space, we only keep adult males here.