This underscores the critical need for baseline inventory of multiple taxonomic 
groups in all parts of the world - not just tropical or remote regions.  Even 
in relatively well studied regions of North America like the northeast we 
generally have a poor understanding of rare species' distributions.  Without a 
basic baseline we cannot expect to accurately predict how sensitive species 
will react to climate change nor will we be able to assess the effects of 
climate change decades in the future.  Yet funding for species inventory 
projects to assist in amassing this baseline data is next to impossible to 
obtain and is often shunned by armchair ecologists with little or no field 
experience as not "real" science.  In fact, many grant programs specifically 
state they will not support survey or inventory work.


Christopher M. Heckscher, Ph.D.
Assistant Professor, Environmental Science & Ecology
Institutional Project Director, NOAA Environmental Cooperative Science Center
Department of Agriculture and Natural Resources
Delaware State University
1200 N. DuPont Highway
Dover, DE  19901

________________________________________
From: Ecological Society of America: grants, jobs, news 
[ECOLOG-L@LISTSERV.UMD.EDU] On Behalf Of Allen Sa;lzberg 
[asalzb...@herpdigest.org]
Sent: Friday, January 06, 2012 9:09 AM
To: ECOLOG-L@LISTSERV.UMD.EDU
Subject: [ECOLOG-L] Climate Change Models May Vasty Underestimate Extinctions

Climate Change Models May Vasty Underestimate Extinctions

ScienceDaily (Jan. 3, 2012) — Predictions of the loss of animal and plant 
diversity around the world
are common under models of future climate change. But a new study shows that 
because these
climate models don't account for species competition and movement, they could 
grossly
underestimate future extinctions.
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"We have really sophisticated meteorological models for predicting climate 
change," says ecologist
Mark Urban, the study's lead author. "But in real life, animals move around, 
they compete, they
parasitize each other, and they eat each other. The majority of our predictions 
don't include these
important interactions."

Plenty of experimental studies have shown that species are already moving in 
response to climate
change, says Urban, assistant professor of ecology and evolutionary biology at 
the University of
Connecticut. For example, as temperatures rise over time, animals and plants 
that can't take the
heat are moving to higher altitudes where temperatures are cooler.

But not all species can disperse fast enough to get to these more suitable 
places before they die
off, Urban says. And if they do make it to these better habitats, they may be 
out-competed by the
species that are already there -- or the ones that got there first.

With coauthors Josh Tewksbury and Kimberly Sheldon of the University of 
Washington, Urban
created a mathematical model that takes into account the varying rates of 
migration and the
different intensities of competition seen in ecological communities. The goal 
was to predict just
how successful species within these communities would be at shifting to 
completely new habitats.

Their results showed that animals and plants that can adjust to climate change 
will have a
competitive advantage over those that don't.

Animals with small geographic ranges, specific habitat needs and difficulty 
dispersing are likely to
go extinct under climate change, their model shows. Further, these animals are 
more likely to be
overrun by other species that can tolerate a wider range of habitats.

"When a species has a small range, it's more likely to be out-competed by 
others," Urban says. "It's
not about how fast you can move, but how fast you move relative to your 
competitors."

Urban likens this scenario to a train traveling up a mountain on a track. If 
each boxcar --
representing a species -- travels at the same speed, they will likely all reach 
the top eventually. But
in reality, each car can move at a different speed, creating a collision course.

"There's always a car in front of you and a car behind," explains Urban. "When 
you introduce the
ability to move at different speeds, they're constantly bumping into one 
another, even running
each other over. It's a recipe for disaster."

Importantly, the authors speculate that current predictions of biodiversity 
loss under climate
change -- many of which are used by conservation organizations and governments 
-- could be
vastly underestimating species extinctions.

Tropical communities, for example, which often have many species living in 
small areas, could be
among the hardest hit by climate change. Urban says this is a first step toward 
making climate
change predictions of biodiversity more sophisticated.

"This is a first step -- to include in our models things that we know are true, 
like competition and
dispersal," says Urban. "Knowing these things, can we predict which species 
might be most at
risk?"

Urban's paper was published in the Jan. 4 online edition of the Proceedings of 
the Royal Society B:
Biological Sciences. The work was funded by the National Science Foundation.

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