BACKYARD BIRDING IN MERIDA, YUCATAN AND BEYOND – PUNCTURED PELICAN POUCHES: AMERICAN WHITE PELICAN, PART 1 OF 2

American White Pelican with blue tilapia (fish)

AMERICAN WHITE PELICAN, Pelicans erythrorhynchos, Pelicano Blanco Americano(Spanish), Sak p’onto’ (Mayan)

Every time I see American White Pelicans I am awestruck at their size. Wing spans of these behemoths can attain 9.5 ft.  They are among the largest flying birds in North America and usually weigh 11-20 pounds with some reaching almost 30 lbs.! Compare these giants with their cousin, the Brown Pelican, or their wading bird neighbors such as Wood Storks, Great Egrets, Roseate Spoonbills, or even with Double-crested Cormorants.

Swimming Brown Pelican approaches flock of American White Pelicans along shore. Two Black-necked Stilts stand close to the pelicans
Size comparison of white pelican to wading birds
3. Double-crested Cormorant size next to American White Pelican

Recently I encountered a migratory flock of three hundred in Florida that stopped over at a shallow lake for three days to forage for sushi and to rest and preen on sandy islands. From a distance they looked like a flock of sheep. I agree with villagers of Lake Chapala, Mexico where these huge birds overwinter, who call them borregones, large sheep. Plus I also photographed them at Chelem and Celestun, Yucatan as non-breeding winter residents of the peninsula along with a small summer population.

Fascinated by their fishing techniques, I compared this Florida flock with what I read about their feeding behaviors and became entranced with pelican bills and pouches! The upper bill ends with a hooked tip that reminds me of Beyonce’s fingernails. That tip helps hold its slippery prey.

Upper bill of American White Pelican
Beyonce’s orange fingernails look like hooked tip of white pelican bill. No copyright infringement is intended
White pelican upper bill hooked tip holds slippery prey

The lower flexible bill can separate widely into two parts to support the attached, expandable pouch. (I’d never thought of that bill and how it would need to split sideways; most lower bird bills are solid.) That pouch of skin can hold three gallons of water. Remember the poem about the pouch holding more than the belly can? It’s true since the belly only holds a gallon of water. Plus the pelican doesn’t fly carrying 25 pounds of water. After using the super scooper to capture its prey, mainly fish and sometimes amphibians and crustaceans, the pelican drains the water by slowly contracting its pouch. Then it rears up its head and bill to swallow the fish.

Flexible lower bill of white pelican separates to support opened pouch

What I noticed differently from references, these pelicans raised and lowered their heads many times before the fish could be swallowed headfirst. It wasn’t a simple process of dip bill in water to catch prey, lift up head and pouch, and gulp. Sometimes, a pelican drained the scoop several times because it refilled it with water again and again to help maneuver the fish into position. That action or even the mere capture of a fish seemed to invite some other pelicans to attempt to snatch the fish away. Perhaps these blue tilapia (fish) were larger than a typical fish they could easily get down the hatch.

White pelican scoops up fish
9 After fish is scooped up, bill is closed and bird readies for head toss
Head tossing of white pelican assists in swallowing prey
Head lowered to reposition fish again
Several more times pelican adds water to pouch to change fish position and then drained
Finally the fish appears to be headfirst in white pelican pouch
Note enlarged pelican neck with swallowed fish

But the more I looked, the more I saw punctured pelican pouches and larger holes.

Punctured pelican pouches
Ripped hole in white pelican pouch
Small and larger holes in American White Pelican pouch
Some small punctures can heal in white pelican pouch

Several references mention the handicap of fish hooks tearing these amazing sacks especially in the Brown Pelican. However, the white pelicans have also regurgitated fish hooks which can cause holes. What I saw inferred damage to the pouch from fin spines while the pelican jousted the fish to devour it. I have another theory I didn’t read about; I think when other pelicans attempt to steal a fish from the capturer or to grab the same fish, that upper bill tip could also tear the pouch. Surely the pelican didn’t say, “Sack it to me, sack it to me, sack it to me!” (Apologies to Rowan and Martin’s Laugh-In tv show)

Perhaps pelican bills rip each other pouches attempting to steal prey
Note upper bill of one pelican is inside another mouth
Other pelicans attempt to steal fish

Stay tuned to Part 2 to learn about more functions of the phenomenal, pliable, pelican pouch and more feeding strategies!

DIP YOURSELF INTO NATURE TO REFRESH YOUR SOUL

DISCLAIMER: REFERENCES DO NOT ALWAYS AGREE ON INFORMATION:

Sal a Pajarear Yucatán, Bird & Reserves of the Yucatan Peninsula, A Guide to the Birds of Mexico and North Central America, The Sibley Guide to Bird Life & Behavior, Lives of North American Birds,

Knopf, F. L. and R. M. Evans (2020). American White Pelican (Pelecanus erythrorhynchos), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, US

https://www.allaboutbirds.org/guide/American_White_Pelican/

https://www.mexconnect.com/articles/1237-did-you-know-mexico-s-largest-bird-is-the-american-white-pelican

https://www.wsfa.com/story/34728255/ken-hares-natural-alabama-torn-throat-pouch-endangers-beautiful-white-pelican/

https://www.jhnewsandguide.com/valley/columnists/a-pelican-holds-more-in-its-bill-than-its-gut/article_f8a921b3-9a5a-5888-9dea-3b62fb3cf86e.html

http://pcwd.info/wp-content/uploads/2015/12/Pelicans.pdf

http://blog.bird-rescue.org/index.php/2018/02/vet-files-pelican-pouch-laceration/

https://sora.unm.edu/sites/default/files/journals/condor/v066n01/p0003-p0023.pdf

https://www.naturalhistorymag.com/htmlsite/editors_pick/1976_12_pick.html

https://digitalcommons.uri.edu/cgi/viewcontent.cgi?article=1716&context=oa_diss

https://birdsoftheworld.org/bow/species/amwpel/cur/introduction

Cherie Pittillo, “nature inspired,” photographer and author, explores nature everywhere she goes. She’s identified 56 bird species in her Merida, Yucatan backyard view. Her monthly column features anecdotes about birding in Merida, Yucatan and also wildlife beyond the Yucatan.

Contact: all4birdies@gmail.com  All rights reserved, ©Cherie Pittillo



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