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oWhere do Cracids Live?
The geographic
distribution (Power
Point Map) of Cracids ranges widely throughout Latin America,
where this family occupies a variety of habitats from the lowland
tropics to the Andean Mountains. The Andean
Guan lives higher than any other Cracid, with one record at nearly
4000 meters above sea level!
Most
species of Cracids live in pristine tropical rainforest; however, there
are exceptions. Chachalacas are associated with secondary habitats,
such as scrub, secondary
forest, and lightly-logged woodland. Several species are
restricted to various habitats in the Andean Mountain Chain. These Cracids
include the Helmeted
Curassows, that are endemic to montane cloud
forest habitats and several
species of Penelope Guans.
In contrast to most Cracids dwelling in the deep interior of the tropical
rainforests, some of the Crax Curassows are found in the aqueous
environments. The Wattled
Curassow is almost always found in the varzea;
the seasonally inundated riverine forest edge. While the Yellow-knobbed
Curassow is found in the llanos; the seasonally inundated
floodplain and proximal gallery forest. Some species are associated
with more than one habitat across their geographic distribution. The Bare-faced
Curassow may be seen in tropical rainforests or Pantanal wetlands. The Crested
Guan is not only associated with different habitats, but
it is also found on different continents! In the northern extent of
its range in Central Mexico this species inhabits montane pine-oak forest.
Further south in Central America the Crested Guan lives in lowland to
montane tropical rainforest. In South America this species occurs west
of the Andes in dry forest.
Several species live in different habitats during different seasons.
The reasons for their seasonal movements are often tied to food availability.
In many lowland tropical rainforest environments, especially Amazonian,
resource availability is dictated by the water level in the river, which
is influenced by snow-melt in the Andes. As a result the Black Curassow migrates to the varzea during the low-water season, and the
terra-firme tropical rainforest during high water season. The Black-fronted
Piping Guan and several of the Andean dwelling Penelope Guans will move from the upper parts of a mountain to the mid-level
or lowland. This is a result of higher food availability at lower altitudes
during harsh cold winters.
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