Penguin Deliberately Target Jellyfish
Scientific research has previously suggested that penguins accidentally consume jellyfish as they are low in calories. But a new study using penguin-cams has shown that the birds actually target these creatures deliberately.
Jellyfish and the other gelatinous creatures in the ocean are not the most energy-rich snacks in the food chain. But penguins clearly love them. In a new study, researchers spotted almost 200 instances of penguins eating a variety of gelatinous creatures.
The study has been published in the journal Frontiers in Ecology and the Environment after the researchers gathered 350 hours of footage from four different species of penguin. These were Adélie penguins (Pygoscelis adeliae), yellow-eyed penguins (Megadyptes antipodes), Magellanic penguins (Spheniscus magellanicus), and little penguins (Eudyptula minor). A total of 106 individuals were involved in the research.
The penguins could clearly be seen hunting various carnivorous species including jelly fish whilst choosing not to pursue plant-eating species. The penguins appeared to be targeting the jellyfish with prominent gonads because the carbon and protein content of the reproductive organs is greater than any other part of the creature. Gelata made up more than 1 percent of the daily needs for Adélie, Magellanic, and yellow-eyed penguins, and up to 2 percent for little penguins.
The research team fitted penguins with tiny video cameras weighing just 22g at seven breeding sites in the southern oceans. The cameras yielded extensive footage. Large animals, including sea turtles and ocean sunfish, were already known to thrive on a diet of jellies. But the researchers were surprised to discover this feeding tactic adopted by penguins. The birds are warm-blooded animals and so require an energy-rich diet to keep their bodies warm.
Higher Calorie Meals
Crustaceans and fish contain more calories per gram than jellyfish and so would appear to be a better choice of meal for the birds which live in regions where the ocean water is very cold. Calories are very important, especially to the penguins which are raising chicks. But the birds were definitely targeting gelatinous meals.
Further research will be required to establish why the penguins like to eat jellyfish. This behaviour could be indicative of changes to the available food caused by climate change. Perhaps penguins just enjoy eating jellyfish. It will be interesting to find out.