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It stands up to the blizzard and faces the raging oceans without flinching. The penguin is a funny animal. With its long beak, its very short scale-like feathers, its plump body resting on two short legs, it seems halfway between a bird and a fish. It is, however, a bird… which does not fly. But never mind, deprived of aerial pirouettes, the penguin twirls in the seas. And there he is like a fish in water: his little flightless wings are absolutely perfect for swimming; in fact, they even look like fins! This gregarious and social animal likes the company of its congeners and lives in large colonies, called penguins. And let’s remove any doubt right away: no, the penguin is not a penguin! The penguin flies, lives in the northern hemisphere and belongs to the family of alcidae while the penguin is a sphenisciform, found in the marine regions of the southern hemisphere, Antarctica, New Zealand, Africa or in Peru. Eh yes ! Contrary to the image we usually have of them, the penguin does not live exclusively on the ice floe: some like to bask in the pill on fine sandy beaches bathed in sunlight, while others take the air over the dark rocks of the Galápagos Islands. But make no mistake about it, our little beast is not afraid of the Deep South: in the icy Antarctic desert, we can see its small silhouette – which measures between 40 centimeters and a little more than a meter – waddling skillfully. Living conditions in Antarctica are difficult, the environment hostile. But there are nevertheless several species of penguins, including the largest of all: the famous emperor penguin.
Because under its air of adorable little stuffed animal, the penguin is an ace of survival. In the event of a storm, for example, nothing to panic: the whole colony unites! Tight against each other, the penguins all keep warm together: they take turns even at the most difficult positions so that the birds at the edge of the group, exposed to the wind, can find a little warmth. In addition to the solidarity of its companions, the penguin can also count on its thick plumage, which protects it from the most extreme cold and allows it to splash around in the most icy waters. And it’s very practical to fill the belly! Because our little beast makes its market in the seas: it feeds on fish, squid, molluscs or even krill, a kind of small shrimp. For this, he has an extraordinary talent: the penguin is indeed able to keep whole fish in his stomach without digesting them, for several days! This is how the penguin’s young, the chicks, which are born in the heart of the harshness of winter, are fed by their parents. They take turns fishing before regurgitating whole fish to feed their offspring. But very often, the fish runs out. Because global warming due to human activities has a direct impact on the penguin’s habitat. Glaciers are receding, the waters of the planet are less populated with fish and krill: penguin populations are decreasing and are threatened with extinction.
For a long time, the penguin was little studied in comparison with other birds. However, behind its friendly little silhouette with a funny gait, hides a brilliant animal whose abilities never cease to amaze scientists. To find out, we embark on an incredible journey: at the southern tip of Africa, at the very end of this immense continent, Cape Town and the Stony Point reserve await us.
African penguin behavior
We are far from the pristine expanses and freezing temperatures of Antarctica. Here in Cape Town, South Africa, in the heart of Stony Point Game Reserve, the skies and waters of Betty’s Bay shine with the same azure. The weather is good and on the rocky beaches, you can admire the intertwining of flowers, seaweed and weeds that the wind sweeps away relentlessly. And then suddenly, here it is. He arrives waddling from the top of his 60 centimeters. His white torso is dotted with black spots that draw a unique pattern. They appeared when he was between 3 and 5 months old and will remain the same until the end of his life. Above his eyes you can see two spots, pink this time: these are glands that become more and more pink as he warms up. He has a little black beak, and an absolutely adorable smug look when he closes his eyes. The Cape penguin is truly the cutest of them all. Spheniscus drowned, that is its Latin name, is endemic to the African coasts: it is found nowhere else on the globe. And studies on its abilities are numerous: it is able to recognize its congeners by their cry, to filter sounds in an extremely noisy environment to select those that interest it (a capacity that we humans also know how to demonstrate) or even to follow the gaze of a comrade – and this is very valuable for detecting a predator.
But Alistair McInnes’ team is waiting for us today to solve another mystery. This researcher knows the Cape penguin well, he works at the University of Cape Town and is a specialist in the study of endangered birds. Today, using good old waterproof tape, he hangs small cameras on the penguins’ backs that will allow us to dive into their world. Once the cameras are hooked up, we’ll be able to follow them on the hunt for sardines. It’s the big dive. On camera, we sometimes see the darkness of the underwater depths, sometimes the light piercing the surface. And that’s normal: the penguin carrying the camera twirls around. He begins a downward dive, the image becomes darker and darker, the water is murky, almost green, and then suddenly he comes back up. Above him, we see what mobilizes all his energy: a bench of sardines. He rushes to the bench, when, not far away, we see for a moment the other penguins doing the same. They try to wedge the school of sardines between them and the surface of the water. This is what researchers call the upswing. During this phase, the school of sardines is disunited and a sardine finds itself alone, away from the others: neither one nor two, our penguin makes short work of it. And the race continues. Then, suddenly, that’s it, we see the sardines struggling, in the bright light of the surface. Very quickly, we hear the cry of other birds, those that can fly: they are attracted by the feast. For the penguins, there is nothing left to do but feast.
In this study, the researchers analyzed more than 800 minutes of spearfishing video. That’s hundreds of scenes like these. And so they filmed Cape penguins hunting in groups. This technique requires you to coordinate with your comrades, to react quickly in the event of a change in the situation, to anticipate the movement of the fish. In short, group hunting is a feat of intelligence. You know it all the better if you listened to our episode on the sardine, which is rather clever, too. But that’s not all: the researchers noticed that the penguins put in place different types of strategies to catch fish that were alone, isolated, that had escaped the protection of their school, or to manage to catch them even when they are grouped. Another point, and perhaps the most important: when the penguin hunts with its congeners, its fishing is more fruitful. This cooperation is therefore effective. Incredible isn’t it? That said, the researchers also found that penguins hunted less in groups than before, when penguin populations were at normal levels. The decline in the number of individuals therefore has an impact on their social organization. Sardines and anchovies, so precious to the penguin, are directly threatened by overfishing and climate change. And their decline has hit penguin populations hard: since the beginning of the 20e century, they have thus decreased by 90%. Thus, the team of Alistair McInnes concludes this fascinating study by inviting us to protect the African penguin. And to do this, they insist, we must preserve the fauna and flora, protect biodiversity, safeguard our place of life.
