Skip to Content

Petrel, Southern Giant

Identify and index birds in Southern Africa
User avatar
Johan van Rensburg
Legendary Virtual Ranger
Legendary Virtual Ranger
Award: Birder of the Year (2015)
Posts: 2373
Joined: Wed Sep 06, 2006 3:33 pm
Location: Jam Street

Petrel, Southern Giant

Unread post by Johan van Rensburg » Tue Apr 19, 2016 5:59 am

The two similar-looking species of giant petrels, the Northern Giant Petrel (Macronectes halli) and the Southern Giant Petrel (M. giganteus), are renowned for being difficult to separate. If seen at close range under good light conditions, bill-tip coloration is a diagnostic feature that allows the observer to differentiate one species from the other: greenish in the southern and reddish in the northern.

The Southern Giant Petrel is the largest petrel, but not so much that size difference becomes a identifying trait in field observations.

Image

Opportunist scavenger and predator, giant petrels (both species) eat penguin, albatross, seal and whale carrion, ship offal and kelp. They also prey on small birds and take fish and squid off the surface.

Southern giant petrels are pelagic and circumpolar, generally found between subantarctic and Antarctic latitudes from 40°S to 68°S, with breeding as far south as continental Antarctica.
698 Latest lifers: Sooty falcon, American golden plover, Temminck's stint, Red-necked phalarope, Cape long-billed lark, Agulhas long-billed lark, Karoo eremomella

User avatar
hilda
Forum Assistant
Forum Assistant
FAC Member (2016)
FAC Member (2015)
Posts: 15284
Joined: Fri Apr 06, 2007 6:39 am
Location: Pretoria SA

Re: Petrel, Southern Giant

Unread post by hilda » Tue Apr 19, 2016 6:25 am

Very interesting of how to differentiate between the Northern and Southern Giant Petrel Johan! Thank you for sharing! :clap: :clap:

User avatar
Johan van Rensburg
Legendary Virtual Ranger
Legendary Virtual Ranger
Award: Birder of the Year (2015)
Posts: 2373
Joined: Wed Sep 06, 2006 3:33 pm
Location: Jam Street

Re: Petrel, Southern Giant

Unread post by Johan van Rensburg » Thu Dec 08, 2016 3:34 pm

Giant petrels were plentiful on a pelagic trip out of Cape Town early in December and I got some good shots of both southern and the closely related northern species, sometimes fitting both together in the camera frame.

Image

Southern Giant-Petrel Macronectes giganteus are a deep-sea pelagic species which spend most of their lives at sea, coming to land only to breed. Southern Giant-Petrels first breed at an age of 10 years and live for over 50 years. Parents incubate the egg and care for the juvenile together, an investment approaching 200 days before the juvenile is ready to feed on its own. Adult breeders tend to stay in the ocean surrounding their breeding site, while juveniles are more likely to disperse further afield. These birds are known to feed on carrion and offal and refuse from ships, as well as cephalopods, fish, and other birds. Interestingly, males and females show preference to different areas in their foraging ranges and males will chase females from their favourite feeding sites.

Southern giant petrels feed on krill, squid, fish, other small seabirds, and carcasses of marine mammals. However, it has been shown that there is a significant dietary difference between the sexes. Females feed more on live prey at sea such as krill, squid, and fish; whereas males feed tend more toward carrion.

Both adult birds and chicks can regurgitate foods and oils to a distance of a metre or more if they are disturbed. The old seal hunters found this out in encounters with these birds and subsequently named them “stinkers”.
698 Latest lifers: Sooty falcon, American golden plover, Temminck's stint, Red-necked phalarope, Cape long-billed lark, Agulhas long-billed lark, Karoo eremomella

User avatar
hilda
Forum Assistant
Forum Assistant
FAC Member (2016)
FAC Member (2015)
Posts: 15284
Joined: Fri Apr 06, 2007 6:39 am
Location: Pretoria SA

Re: Petrel, Southern Giant

Unread post by hilda » Fri Dec 09, 2016 4:33 pm

The Southern Giant Petrel is really a Giant Johan! They are huge! Thank you for the interesting information about them! :clap: :clap:

User avatar
Johan van Rensburg
Legendary Virtual Ranger
Legendary Virtual Ranger
Award: Birder of the Year (2015)
Posts: 2373
Joined: Wed Sep 06, 2006 3:33 pm
Location: Jam Street

Re: Petrel, Southern Giant

Unread post by Johan van Rensburg » Sat Dec 10, 2016 6:12 am

hilda wrote:The Southern Giant Petrel is really a Giant Johan! They are huge! Thank you for the interesting information about them! :clap: :clap:


With a wingspan of up to 2m and weighing as much as 6kg, the giant petrels are rather of medium size when one looks at tubenoses in general, here the wandering albatrosses steal the show with wingspans that can exceed 3.5m, sometimes weighing as much as 12kg!
698 Latest lifers: Sooty falcon, American golden plover, Temminck's stint, Red-necked phalarope, Cape long-billed lark, Agulhas long-billed lark, Karoo eremomella

User avatar
hilda
Forum Assistant
Forum Assistant
FAC Member (2016)
FAC Member (2015)
Posts: 15284
Joined: Fri Apr 06, 2007 6:39 am
Location: Pretoria SA

Re: Petrel, Southern Giant

Unread post by hilda » Sat Dec 10, 2016 8:56 am

Amazing! :dance: :dance:


Return to “Birding in Southern Africa”

Who is online

Users browsing this forum: bishop3006 and 4 guests

Webcam Highlights

Addo
Submitted by imcarthur at 14:09:05
orpen
Submitted by Ton&Herma at 20:36:27
satara
Submitted by Ton&Herma at 12:29:48
nossob
Submitted by Trrp-trrrrrrrr at 12:34:54