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Accounts of eXtinct Species

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destroyed. furthermore, as granivores, they were seen as. an agricultural pest, and destroyed in large. numbers by farmers. the negative synergistic ... – PowerPoint PPT presentation

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Title: Accounts of eXtinct Species


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Accounts of eXtinct Species
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Passenger Pigeon (Ectopistes migratorius)
(Rest in peace, Martha!)
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Distribution
the passenger pigeon lived in the eastern U.S.
and was found from Canada to the Gulf of Mexico
a short-distance migrant, birds from far
northern climates wintered in the south
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Description
large pigeon with a long pointed tail
gray upper, with tip of wings and tail black
throat and breast rust-colored
red-colored eyes
females dull brown-colored, with black eyes
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passenger pigeons placed their nests in trees,
8-50 ft. from the ground
laid one to two eggs per clutch
nested in colonies which sometimes occupied
hundreds of square miles
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passenger pigeons were once so numerous that when
they migrated, it was estimated that more than a
billion birds passed in flocks miles long which
lasted for days
as John James Audubon noted of the flocks the
air was literally filled with pigeons
the light of noonday was obscured as by
eclipse the dung fell in spots, not unlike
melting flakes of snow
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this bird was seemingly so overabundant that no
one ever thought that there could possibly be a
shortage of them
both the eggs and the flesh were favored foods
because the pigeons nested in huge colonies where
food was plentiful, they were easy prey
Wilson (1814) reported Wagon loads of them
are poured into marketand pigeons are the order
of the day at breakfast, lunch, dinner, until the
very name becomes sickening.
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rampant over-harvesting for both food and sport
took place
as the turn of the century approached, vast
amounts of forested land were cleared, for
timber, towns, railroads, and agriculture
as the railroad systems expanded in the
1850s, more and more birds could be easily
shipped into the increasing city markets
11
as the turn of the century approached, vast
amounts of forested land were cleared, for
timber, towns, railroads, and agriculture
enormous numbers of chestnut and oak trees, the
main food source of the pigeons, were destroyed
furthermore, as granivores, they were seen as an
agricultural pest, and destroyed in large
numbers by farmers
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the negative synergistic whole of all these
events took its toll on the passenger pigeon
the last major pigeon nestings occurred near the
eastern shore of Lake Michigan in 1881 and in
Wisconsin in 1882
small flocks and pairs continued to nest into
the 1900s, free from commercial persecution
however, the passenger pigeon could not sustain
itself at these drastically reduced numbers
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the last legitimate record of a wild passenger
pigeon was in 1900 in Ohio
this bird was shot and its remains are in the
Ohio State Museum
in 1909, the Cinncinnati Zoological gardens
had only 3 birds remaining two males and one
female
on 1September, 1914, the last passenger pigeon,
Martha, died in the Cinncinnati Zoo
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If the land mechanism as a whole is good,
then every part is good, whether we
understand it or not. If the biota,
in the course of aeons, has built something we
like but do not understand, then who but a fool
would discard seemingly useless parts?
To keep every cog and wheel is the
first precaution of intelligent tinkering.
- Aldo
Leopold, 1953
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