Whilst bumbling round South America during our little Andes adventure this year, we were really excited to see flamingos in the wild for the first time. Flamingos are bizarre in appearance with unusual characteristics which set them apart from every other bird, and you’d be blind to miss them in this part of the world. In actual fact we ended up bumping into flamingos at every turn (not quite), but they were present in every country we visited (Argentina, Chile, Peru, Bolivia). If you’re as curious as we were about them, you’d probably ask the obvious few questions, which I’ve set out to answer below. So read on to discover three (not so) secrets of the flamingos.
Why are flamingos pink?
Seriously, how many other birds are pink? I’m struggling to think of one off the top of my head. Somehow, flamingos must have found a peculiar physical niche where it is beneficial to be pink, as it’s not a favoured trait amongst birds. Firstly let’s answer ‘how’, and then we will tackle ‘why’.
It’s all in the diet. Flamingos generally dine on small crustaceans on muddy shores and shallow lakes. If not they pick at algae, which contain pigments called carotenoids – these carotenoids are further broken down by the liver to produce orange and red pigments. The pigments are absorbed by the fat and oil which is secreted all over a flamingo’s body, yes, they’re kind of sweating pink.
Crustaceans also eat the algae, so the same process occurs when they are consumed. However, since the pigments have already been someone absorbed by the crustacean, a flamingo eating solely crustaceans will be lighter than one on a diet of algae. This is why in zoos, they feed flamingos pigment additives and bright pink shrimps, to make them look as vivid as possible.
So why does a bright colour help, or is it a side-effect of having a healthy coating of fats? Well in fact it’s a combo of the two. A study from Spain showed that both sexes of flamingo secreted excess oils coming up to the mating season. It is therefore believed that pinker birds appear more appealing to the opposite sex, suggesting an ability to collect more food and a consequential increase in overall fitness.
Why do flamingos stand on one leg?
The classic image of a flamingo is nearly always on one leg, almost statuesque in a shallow pool. Indeed they do have two legs, and they do move – so why this bizarre resting posture? Well, this is where a bit of physics comes into play, as well as some flamingo biology you might never have guessed…
Firstly you’ll be surprised to hear that what we thought was the flamingo’s knee, was actually it’s ankle. They just have an extremely long vertical ‘foot’ and webbed toes, you could imagine it a bit like them standing on tip-toes all day long. The real knee is hidden inside their feathers just out of sight, so a flamingo is basically doing life-long tip-toe squats – intense.
The benefit of standing like this is (rather counter-intuitively) stability. When the other leg is raised, the foot comes up just in front of the hidden knee, this shifts the centre of gravity towards the head. The bird tilts slightly forwards, pulling the hip and knee joint forwards too, locking them directly above the standing ankle. It’s a process of small shifts, all coming together in a remarkably stable outcome – so much so that flamingos can remain standing perfectly after they’ve died. This position can only happen thanks to the shifting weight provided by the folded leg, so a two legged flamingo is a wobbly flamingo.
The reason behind this adaptation is still a mystery however. Some believe it is to save energy (which certainly happens) as they remain completely still. Also theories to do with retaining body heat are very possible; only one leg becomes cold in the lake whilst the other is warmed up inside the feathers, a study could be done to examine whether flamingos have a preferred leg.
Why do you find flamingos in such extreme environments?
Flamingos are tough beasts. We found them all the way up the Andes range, from southern Patagonia to the coast of Peru, with altitude varying from 0 – 5000m. So what makes flamingos so tough, and where do they prefer to live?
Flamingos love a good shallow lake or coastal (littoral) zone. Their beaks are perfectly designed to scoop up crustaceans and molluscs on silty substrates. They waved their head from side to side and filter the food on a sieve like structure in their mouths.
Ideally a lake would be salty and slightly alkaline in order to support their preferred diet. Luckily there are a lot of these environments round the world, and although enjoying large flat areas, they thrive on the Andean Altiplano which stretches for thousands of miles up the west of South America. Furthermore, these environments are often relatively uninhabited, so flamingos have little competition or predation.
It is believed that flamingos prefer a tropical environment, one which they’re commonly associated with. However, in colder regions, flamingos also thrive, often being frozen on one leg overnight in icy lakes! This shows that the chemical and biological balance of the habitat is more important for the flamingo. Acid rain from nearby urbanisation is something can severely affect this habitat, by disrupting the pH balance of the water. After a particularly heavy bout of rainfall during prior months, we observed a distressing graveyard of body parts washed up on the shores of Laguna Colorada in Bolivia.
It is important to remember that something seemingly so isolated can still be negatively affected by cities hundreds of miles away. The chemicals released into the air travel huge distances within clouds, and the repercussions are seen here. Sadly the link will appear too tenuous for industries to do anything about it, yet another argument for renewable energy sources. Hopefully flamingos are tough enough to wait it out until we can make the world a cleaner place, and amazingly unique animals such as this one will continue to thrive without threat.