[DOC] [TLE] Why the Passenger Pigeon Went Extinct | Audubon [PAR] And whether it can, and should, be brought back to life a century after it 
disappeared. ... I beheld moving toward me in an unbroken front millions of 
pigeons, the first I ... pigeon migrations: how they took hours to pass over a single 
spot, darkening ..... other accounts have said the passenger pigeon went from 
billions to extinct... [DOC] [TLE] Passenger pigeon - Wikipedia [PAR] The passenger pigeon or wild pigeon (Ectopistes migratorius) is an extinct 
species of pigeon ... The last confirmed wild bird is thought to have been shot in 
1900. ... Martha, thought to be the last passenger pigeon, died on September 1, 
1914, ..... the large numbers in the flocks, the excrement they produced was 
enough to... [DOC] [TLE] From Billions to Zero in 50 Years: The Extinction of the Passenger ... [PAR] Feb 18, 2014 ... The passenger pigeon once dominated the North American skies. ... may have 
been much less in North America, but after a huge percentage ... Legends 
abound about how these birds used to black out the sky when they moved en 
masse. ... In fact, it's estimated that the largest flocks of passenger pigeons... [DOC] [TLE] Extinction of the Passenger Pigeons  Damn Interesting [PAR] Jun 28, 2006 ... The story of the extinction of the Passenger Pigeon is a dark one. ... between 3 
and 6 billion Passenger Pigeons darkened the skies over eastern North America. 
.... A full blown flock must have been a sight to see, although I hate to think .... It's 
sad, that they all died, that they befell the same fate as the Dodo. [DOC] [TLE] Amazon.com: Customer Reviews: A Feathered River Across the Sky ... [PAR] It has been many decades since a book was devoted to passenger pigeons and 
... There were a few captive flocks, but they did not prosper. .... A Feathered River 
Across the Sky: The Passenger Pigeon's Flight to Extinction ... Over a billion 
pigeons flew over Toronto in May of 1860, yet by 1914 only one was left in the 
world. [DOC] [TLE] A Centenary for the Last Passenger Pigeon - Live Science [PAR] Aug 30, 2014 ... Hunting did not wipe out the passenger pigeon  extinct 100 years as of Monday 
... after Martha Washington) died in the Cincinnati Zoo on September 1, 1914. ... 
the skies and stirred wonder and awe in the immensity of its flocks as ... they have 
never been observed to return to the northern countries in the... [DOC] [TLE] Are Passenger Pigeon populations overestimated? [Archive ... [PAR] By 1900 they were rare; by 1914 they were gone. But were there really flocks of 2
-3 billion that could darken the sky for days as they passed, ... Over 150-million 
have been killed in a year, with no visible effect on their numbers. ... Passenger 
Pigeons didn't breed in the same areas from one year to another. [DOC] [TLE] A Tale of Three Superdoves: the Dodo, the Rock Pigeon, and the ... [PAR] Apr 15, 2014 ... Two (the Passenger Pigeon and Dodo) are gone; the other (the Rock ... The real 
story of the superdoves is yet to be written, but we have enough data to realize ... 
A single flock in motion could darken the sky over 180 square miles. ... marked 
the extinction of a species that had once numbered in the billions. [DOC] [TLE] TYWKIWDBI ("Tai-Wiki-Widbee"): Audubon describes a profusion of ... [PAR] Passenger Pigeon (Extinct: 1914) Billions of passenger pigeons lived in ... John 
James Audubon reported seeing a flock so large that it took 3 days to pass over. 
... It's been a hundred years since one of the most emblematic animal species in 
.... America, sometimes darkening the sky overhead for hours as they passed. [DOC] [TLE] A Feathered River Across the Sky: The Passenger Pigeon's Flight to ... [PAR] I still can't fathom flocks of *billions* crossing the sky- must have been like a 
feathery, poopy ... After reading Avery's A

Question: Once moving in flocks of over a billion, enough to darken the skies, they've sadly been extinct since 1914
Answer: passenger pigeons