The greater flamingo (Phoenicopterus roseus) is the most widespread and largest species of the flamingo family. It is found in Africa, on the Indian subcontinent, in the Middle East, and in southern Europe. The greater flamingo is the largest living species of flamingo.The coloration comes from the carotenoid pigments in the organisms that live in their feeding grounds

Made with Sony A99m2 and Sony 70-200mm f/2.8G with SAL 20TC
(source: Wikipedia)

hunting from nearby tree, about 10:30am, looking intently down at snow, then landed and mantled for a couple of minutes, burying its head into the snow several times before flying off in the opposite direction

The provenance of this Great White Pelican has not been satisfied. Its is an Old World species, having never been recorded in the U.S. before. This female Great White Pelican spent three days in February 2016 at Ding Darling NWR on Sanibel Island, Florida, creating quite a stir. When it flew off in the company of American White Pelicans, its never reported again. Until it returned the following February for just a day. So were did it come from and were did go.
https://www.hngn.com/articles/184259/20160302/rare-great-white-pelican-appears-at-florida-refuge-4-000-miles-from-home.htm
http://blog.aba.org/2016/03/abarare-great-white-pelican-florida.html

just for fun; part of one of 12 quagga breeding programs aimed at bring back the quagga from extinction - not sure how many generations these guys are - prob 5th or 6th and looking pretty good, some have the orange tinge, lack of stripes on lower half, etc

Are these males losing their breeding plumage, or females?

They were hanging out calling repeatedly and foraging for food together. Caught this very cute moment when they both had this bit of plant in their beaks.

Feeding in the shallows on a low but incoming tide. Was in the middle of a large number of oystercatchers and black backed gulls until the water level saw them depart. Had to fight off a couple of gulls to keep its catch. Flew off to the east after 20 min of observing.