Skip to Content

Prion, Antarctic

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: 2544
Joined: Wed Sep 06, 2006 3:33 pm
Location: Jam Street

Prion, Antarctic

Unread post by Johan van Rensburg » Mon Jul 31, 2017 12:06 pm

The pelagic birding trip out of Saint Lucia this past weekend produced very good views of Antarctic prions and subsequently I got a few good shots of this species.


I have come to appreciate that the identification of prions at sea is very difficult making them the LBJs (Little blue jobs) of the oceans. :doh: They are abundant and the four species of whalebirds that occur in South African waters have very similar plumages: a white body, bluish grey upperparts with a dark M on the back and upper sides of the wings when seen from above. The main difference between the species lies in the shape of the bills.

The prion species that may be encounter in our waters listed in order of width of the bill, broadest first:
1. Broad-billed Prion, Pachyptila vittata
2. Salvin’s Prion, Pachyptila salvini
3. Antarctic Prion, Pachyptila desolata
4. Slender-billed Prion, Pachyptila belcheri.

Most abundant is the Antarctic Prion that has an estimated global population of around 50 000 000. It is also the default prion in our region. When a flock is encountered, you hope that is a mixed group and the challenge then is to find the odd one and get good photographs of it for later feeding your “prionitis” – the craving for finding and collecting one of the rarer prions for your life list.

Like some other forms of marine birds, the Prions store a nutrient-rich kind of oil in a section of their stomach. This foul-smelling oil can be sprayed out at predators in a defensive measure, used to feed themselves during long flights, or can be used to feed their young.

Also, like many other marine birds, Prions have a gland that excretes a saline solution to help get rid of excessive amounts of salt swallowed while feeding from the ocean.

A flock of Prions at sea is sometimes evidence of nearby whales. Whales drive fish to the surface of the water, making it easier for the Prions to grab their lunch. This association with whales may account for the reference “whalebirds” to describing this collection of prions.

Another interesting and quite plausible take on the name “whalebird” suggests that it was earned by the feeding mechanism of prions, most pronounced in the Broad-billed Prion. They feed on tiny copepods using their specialized filter-feeding bill. Like mini baleen whales, they use an extendable throat pouch to gulp in a good serving of copepod soup, and then sieve out the water through the rows of lamellae on the sides of their upper mandible, retaining the critters.

Prions live about 15 to 20 years.
728 Latest lifers: Hartlaub's babbler, Coppery-tailed coucal, Red-billed spurfowl, White-browed coucal, Scharlow's turaco, Copper sunbird, Long-toed lapwing, Eastern bronze-naped pigeon, Malagasy pond heron, Soft-plumaged petrel, Orange-winged pytilia.

User avatar
Karin Mitton
Senior Virtual Ranger
Senior Virtual Ranger
Posts: 9300
Joined: Fri Jul 25, 2014 10:56 am
Location: Jhb

Re: Prion, Antarctic

Unread post by Karin Mitton » Mon Jul 31, 2017 3:01 pm

Wonderful info on a really pretty bird!
:clap: :clap:

User avatar
Forum Assistant
Forum Assistant
FAC Member (2016)
FAC Member (2015)
Posts: 19606
Joined: Fri Apr 06, 2007 6:39 am
Location: Pretoria SA

Re: Prion, Antarctic

Unread post by hilda » Sat Aug 05, 2017 1:51 pm

Perfect shot of this beautiful Prion Johan! Very interesting information, and I love the description "LBJs (Little blue jobs) of the oceans". :clap: :clap:
"It is during our darkest moments that we must focus to see the light". Aristotle Onassis.

Return to “Birding in Southern Africa”

Who is online

Users browsing this forum: No registered users and 2 guests

Webcam Highlights

Submitted by Pikkewyn101 at 23:32:42
Submitted by EElse at 12:10:59
Submitted by SYLVIAC at 20:27:10
Submitted by Jennie at 21:41:29