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Showing posts from March 22, 2009

Whooping Cranes had bad year

""Whooping Crane Census Flight

March 15, 2009

The ninth aerial census of the 2008-09 crane season at Aransas was
conducted March 15, 2009 with USFWS observer Tom Stehn in a Cessna 210
piloted by Gary Ritchey of Air Transit Solutions of Castroville,

Texas. ......

Whooping Crane Numbers

With estimated losses that has occurred at Aransas this winter, the current
flock size is estimated at 226 adults + 23 juveniles = 249. The estimated
peak winter flock size was 232 adults + 38 juveniles = 270 total.


Mortality

Today's flight provided evidence of 3 additional mortalities, with total
winter mortality now estimated for the winter at 6 adults and 15 chicks
totaling 21 whooping cranes, a loss of 7.8% of the flock that was a record

270 in the fall. In the last 20 years, the current winter ranks as the
worst in terms of mortality, ahead of 1990 when 7.5% of the whooping cranes
(11 out of 146) died at Aransas. The 3rd worst winter in 1993 showed a

4.9% loss at Aransas (7 out of 143). Mortality i…

Birds buffer against virus

"18-02-2009

North American scientists studying West Nile virus have shown that more diverse
bird populations can help to buffer people against infection. Since the virus
first spread to North America it has reached epidemic proportions and claimed
over 1,100 human lives. “This is an important example of the links between
biodiversity and human health”, commented Dr Stuart Butchart, BirdLife's
Global Research and Indicators Coordinator.


Biodiversity is increasingly being recognised as socially and economically
important because of the valuable services it provides. The authors of this
latest research - John Swaddle and Stavros Calos - highlighted the
“increasing evidence for economically valuable ecosystem services provided by
biodiversity”. "

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"Scientists studying the virus looked at US counties east of the Mississippi River and compared their avian diversity with the number of human cases. They found that high bird diversity was linked with low incidence of the…