If you love penguins, you probably won't like giant petrels.
Giant petrels (of the genus Macronectes) are impressive birds. They can reach a wingspan of around 2 metres (equaling that of small albatrosses) and live in Antarctic and sub-Antarctic regions. Their appearance is made all the more intimidating by their powerful bill, which they use to drag and hold prey and tear it apart. Should adultbirds or chicks be disturbed, they can regurgitate and spit stomach oils at their attacker.
Giant petrels have earned infamy through their appetites and hunting techniques. Like other birds they feed on krill, squid and fish, but they are also known to kill other seabirds (penguins, gadfly-petrels and the occasional albatross) and scavenge carcasses of marine animals. They've been seen to stab surfacing penguins with their bills and drop onto them from the air. But like crocodiles, they know how to make use of drowning - one report states penguins were "grasped by the hind-neck and held underwater for 5–6 minutes until they stopped struggling".
The report on an immature albatross attack highlights the same techniques, noting the "confident manner in which it immediately grasped the Albatross's head from behind, pushed it under water, then forced it down with its weight." The author concluded this petrel may have had experience killing large seabirds, but suggested these attacks only occur in extreme circumstances.
Photo: Northern giant petrel (one of the two Macronectes species) eating a dead elephant seal pup. Credit to Lauren Demongin.
The southern giant petrel: http://bit.ly/116O1l7
The northern giant petrel:l http://bit.ly/10ItFfL
The oil-spitting abilities of giant petrels and their relatives:http://bit.ly/11GipD8
Giant petrels and rockhopper penguins: http://www.bioone.org/doi/abs/10.5253/078.096.0116
A case of a giant petrel killing an albatross: http://bit.ly/XvNPfc
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