Event:
Date: Monday, October 2nd., 2006
Time: 6:30 p.m.
Place: Historic Brownsville Museum located at
the old Southern Pacific Depot at 7th and East Madison Streets.
Admission: Free
The Rio Grande Delta Audubon Chapter meets at 6:30 p.m. on the the first
Monday of each month at the Historic Brownsville Museum, 7th and East
Madison.
Tamaulipas Crow Sanctuary Proposal
Come help us make a conservation impact on Brownsville
to remember. Your comments and support are a necessary part of this project.
Watch our web site www.riograndedeltaaudubon.org for
updates on this project.
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For the
monarch and other butterflies rain is not a trivial matter. An
average monarch weighs roughly 500 milligrams; large raindrops
have a mass of 70 milligrams or more. A raindrop this size striking
a monarch would be equivalent to you or I being pelted by water
balloons with twice the mass of bowling balls.
Overcast skies limit their ability to gather the solar radiation needed
to take wing. A butterfly knocked from the air by raindrops thus faces
the double threat of crashing in an inhospitable habitat where predators
lay in wait and being unable to warm its body sufficiently to regain
flight.
Butterflies are quiescent when it is dark and take refuge in protected
locations called roosts within one or two hours of sunset. Roosts may
be tall grasses, perennial herbaceous plants, and tangled thickets of
woody shrubs, undersides of large leaves, caves or, in some cases, man-made
objects such as fences or hanging baskets. Butterflies may also roost
in the vegetation beneath overhanging trees. The leaves of the upper
canopy intercept raindrops and reduce their impact on vegetation and
butterflies below.
Butterflies hide when it rains. They usually go to the same places they
do for the night. Some butterflies hide under large leaves, some crawl
down into dense leaves or under rocks, and some just sit head down on
grass stems or bushes with wings held tightly. If the rains are exceptionally
hard or of long duration many of the butterflies become tattered or die.
Ultimately, what butterflies do in the rain
is avoid it. But with the return of sunshine following a summer
shower, they often resume within minutes. So the next time the
sky darkens and thunder rumbles, take a cue from the butterflies.
Find a safe roost out of the rain!
Michael Raupp, professor of entomology at the University of Maryland http//:www.sciam.com
Two samples: 88 is a hollow in a rock clift
going from Gomez Farias to Alta Cima. The other is at El Salto
in a small dark cave.
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