Marine selfies: the scientists took video of how penguins prey on jellyfish

© Photo : Pierre Chevaldonné / CNRS / IPEVМедуза and the penguin in the Antarctic waters of the oceanMarine selfies: the scientists took video of how penguins prey on jellyfish© Photo : Pierre Chevaldonné / CNRS / IPEV

. Environmentalists saw as the penguins purposefully find translucent jellyfish in the sea and catch them by attaching an unusual «hidden camera» to the neck of birds, according to a paper published in the journal Frontiers in Ecology and the Environment.

«According to our observations, jellyfish and other «gelatinous» sea organisms are not just random prey for the penguins during their travels around the southern oceans. In the past, we have found evidence that seabirds and Tunas can sometimes eat jellyfish, however, our videos show that the penguins can eat a huge number of these creatures every year,» says Jean-Baptiste Thibault (Jean-Baptiste Thiebot) from the National Institute of polar research in Tokyo (Japan).

The food habits of many birds, mammals and other large vertebrates remain a scientific mystery. The reason for this is their habitat — marine life is extremely difficult to find in the thickness of oceanic waters, and even more difficult to follow their movements and even what foods they prefer to eat and how they are produced.

For example, today scientists believe that penguins feed mainly on fish and krill, however, the analysis of the contents of their stomachs often shows that these birds do not disdain and invertebrate sea creatures and other types of animal food that they are able to produce.

Thiebaud and his colleagues, under the leadership of Watanabe Yuki (Yuuki Watanabe) for several years trying to uncover the role of these unusual sources of calories in the survival of penguins, observing their behavior using self-contained hidden cameras that are attached to the backs of birds. Four years ago they found out that penguins like to eat small fish Pagothenia borchgrevinki and shrimp from the family of Euphausia, and uncover some strategies of their hunt.

Continuing these observations, the researchers found a similar camera on the back of a new «batch» of birds belonging to the species of penguins that live or swim far enough to the North and removed long distances from nesting.

Analysis of approximately 350 hours of «video selfie» taken with the penguins for a few months of their travels in the South seas, scientists have discovered an unusual thing. It turned out that just four species of birds – Adelie penguins, Magellanic, and yellow-eyed their «cousins» and small piquini — sought out, caught and ate jellyfish, a large number of which appears in the waters of the oceans of the southern hemisphere in the summer months.

Such a lunch, as scholars have noted, was hardly the only means of sustenance for the feathered inhabitants of the Arctic – jellyfish almost completely consist of water and they gave the birds only 1-2% of the calories needed for their survival. On the other hand, you can not say that birds were caught jellyfish by accident, as they pursued only a predatory jellyfish that was more «calories» and didn’t touch them planktivorous «cousins».

In the near future, scientists plan to conduct repeated observations of similar hunting penguins with the new cameras, as the batteries inserted in the camera Little Leonardo DVL200, only enough for 15 hours of shooting that does not allow scientists to track how the birds are returning home. These observations, as I hope Watanabe and his colleagues, will help to understand what is the role of jellyfish in the diet of penguins and hunting of birds they affect the entire ocean ecosystem as a whole.