A Northern Giant Petrel drowns and feeds on a Cape Gannet

Jean Tresfon 1

Jean Tresfon 0
"A Northern Giant Petrel grabs an unfortunate Cape Gannet by the neck"

Jean Tresfon is a marine conservation photographer noted for his work along and off the South African coastline.  His recent observation of an ACAP-listed Northern Giant Petrel Macronectes halli (Least Concern) attacking and killing an Endangered Cape Gannet Morus capensis, and then feeding from its corpse, is noteworthy, both for his photographs and his use of dramatic language, made offshore from Tshani on the Wild Coast, Eastern Cape in the Indian Ocean.

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"The Northern Giant Petrel forcibly holds a Cape Gannet by the neck and shoves its head underwater"

He writes; “The ocean is full of surprises and despite having been on the sardine run [of South African Pilchard Sardinops sagax] almost every year since 2009, I continue to witness animal behaviour that I would not have thought possible.  This year was no different and on one particular morning, shortly after having launched, we spotted circling gannets nearby and went to take a closer look.  The gannets were circling high up, clearly interested in the splashing that was happening on the surface below them but making no attempt to dive.  Getting closer we could see a pair of large brown wings flapping and something white.  As we arrived it turned into the amazing sight of a Northern Giant Petrel fighting with a Cape Gannet.

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"Using its savage look beak to good effect, the Northern Giant Petrel rips flesh from the back of a Cape Gannet and eats it"

Gannets are big birds, with a 1.8-m wingspan and weighing in at around 2.5 kg, but this was not an even match. The Northern Giant Petrel is in another class entirely, with a wingspan of over 2 m and weighing up to 5 kg.  But why was it attacking the gannet?  The giant petrel grabbed the gannet by the neck, shoved its head underwater and proceeded to drown it.  The gannet put up a good fight, but the outcome was inevitable, and the gannet finally succumbed to its brutal attacker.

The giant petrel then proceeded use its savage-looking beak to pluck feathers from the gannet before ripping it open and partially eating the belly innards as well as some of the meat from the gannet's lower back” [edited].

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Jean Tresfon 5"The remains of the Cape Gannet immediately after being killed and partially eaten by a Northern Giant Petrel"

Information and photographs from the Facebook page of Jean Tresfon.

John Cooper, ACAP Information Officer, 20 July 2022

The Agreement on the
Conservation of Albatrosses and Petrels

ACAP is a multilateral agreement which seeks to conserve listed albatrosses, petrels and shearwaters by coordinating international activity to mitigate known threats to their populations.

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