Transcript ppt - University of Colorado Boulder

Are Alpine Species
Disappearing?
The Effects of Climate
Change On Alpine
Vertebrates In the Rocky Mountains
Chad Martens
Winter Ecology – Spring 2005
Mountain Research Station – University of Colorado, Boulder
Climate Change and the Alpine
• Is Our Climate Changing?
• Why Are Alpine Ecosystems a Good Place to Study Climate
Change?
• How is Climate Change Broadly Affecting the Alpine?
• What Are the Effects of Climate Change On Alpine
Vertebrates, specifically:
* The Yellow-Bellied Marmot
* The Pika
* The White-Tailed Ptarmigan
• How do winter stresses corespond with climate change?
• What does the Future Hold For These Vertebrates?
• What can be done to prevent these species from
dissapearing?
Is Our Climate Changing?
 Global average temperatures have increased by 0.6
degrees centigrade in the past 100 years
 Lowest elevation at which freezing occurs in mid-latitude
mountains has climbed 150 meters since 1970
 Sub-alpine firs and Engelmann spruces have moved 50
or 60 meters upslope since 1990 in Banff National Park
Why Is The Alpine A Good
Ecosystem To Study Climate Change?
 Well defined boundaries of
treeline-alpine ecotone (changes
can be easily marked)
 The biota of the alpine is
extremely sensitive to disruption
 “Space for time” comparisons
(the most rapid changes in the
smallest amount of time space)
 Fewer direct human influences to
interfere with detection
 Species are essentially stranded
(no place to go)
What Are the Broad Effects of
Climate Change On the Alpine.
Invasion of trees to alpine meadows
Relative increase in height of treeline and
timberline
Increased snow cover and precipitation
Changes in plant vegetation
Increase of invasive species from lower
elevations
How is Climate Change
Affecting the
Following Alpine Vertebrates:
• Yellow-Bellied Marmots
• Pikas
• White-Tailed Ptarmigans
The Yellow-Bellied Marmot (Marmota flaviventris)
Characteristics that Make them Susceptible to Climate
Change
 Need to consume a certain
amount of vegetation in order to
survive hibernation
 Marmots require treeless terrain in
order to spot predators so:
 If trees invade the alpine, marmots
could be more susceptible to
hiding predators
 Limited suitable Habitat
(disconnected “habitat islands”)
 Cannot easily migrate (especially
through lower elevation valleys)
How Do Winter Stresses for Marmots
Correspond with Climate Change?
 Marmots hibernate for the winter in order to avoid the
harsh conditions
 There emergence from hibernation is based on
temperature
 Marmots must immediately begin obtaining food when
the emerge from hibernation, because they have usually
used all of there fat reserves while hibernating over
winter
 Maintaining body temperature in the spring without an
adequate food supply increases stress
Climate Change And Yellow-Bellied
Marmots
 Marmots have gone extinct in some Great Basin mountain
ranges (Floyd 2004)
 Marmots are emerging from hibernation 38 days earlier than they
were 23 years ago in response to warmer spring temperatures
 There is an average of 57cm more snow when marmots emerge
than there was 23 years ago
 Even though temperatures are higher, there still might be
persistent snowpack, which in turn:
 Severely limits available edible vegetation for emerging marmots
and requires them to be euthermic (or drawing on remaining fate
reserves
 Marmots could face starvation if temps continue to rise and
increased snowfall continues
First Sighting of Marmots and
Snowpack at First Sighting
Graphs from RMBL
The Pika (Ochotona princeps)
Characteristics that Make them Susceptible to Climate
Change
 Limited suitable Habitat
(disconnected “habitat islands”)
 Cannot easily migrate (especially
through lower elevation valleys)
 Spend entire life within a half-mile
radius
 Densely furred (cannot dissipate
heat easily)
 Unable to survive even six hours
in temperatures as low as 77
degrees Fahrenheit when not able
to behaviorally thermo regulate
How Do Winter Stresses for Pikas
Correspond with Climate Change?
 Pikas are highly active throughout the year so:
 They must gather and cure vegetation
throughout summer for over winter survival
 Hot temperatures force pikas inside, therefore
reducing there amount of food
 High activity in the hot summer months can
create direct thermal stress
 Early maturation of vegetation associated with
increased temperatures can increase stress
 Increased snow cover limits foraging
Climate Change and the Pika
“American pikas are like the canary in the coal
mine” Caterina Cardosa (WWF)
 In the past 86 years, Pikas have vanished from 9
out of 25 or 36% of the test sites in the Great
Basin.
 In a study published in 2003, pika populations
were detected in only five out of seven resurveyed sites that had pikas in the mid to late
1990’s.
The White-Tailed Ptarmigan (Lagopus leucurus
Characteristics that make them susceptible to Climate
Change
 Heavy plumage
(feathered legs, feet,
and nostrils)
 Die from overheating
when temperatures
exceed 95 degrees
Fahrenheit for one
 Can only survive in
very selective habitats
How Do Winter Stresses for
Ptarmigans Correspond with Climate
Change
 Ptarmigans are dependent on snow drifts for
protected roosting hollows, so
 If climate change reduces snowfall and
protection is reduced, ptarmigans can die from
exposure
 In winters with extreme weather, reproduction
and subsequent recruitment are lowered
 High winter minimum, high mean monthly, and
high mean winter monthly temperatures retard
growth rates
Climate Change and the White-Tailed
Ptarmigan
 Decline to about 1/3 of its peak size
 Decline in populations form 1975 to 1990
 Heavy and persistent spring snowfall delayed nesting
success and decreased breeding by four times the
natural rate
 Median hatch dates advanced significantly (about 15
days) from 1975 to 1999 in response to increase
temperatures in April and May
 Future warming will accelerate declines of ptarmigan
abundance
*The CCC (Canadian Climate Center) predicts a temperature
increase of 2.3 degrees centigrade by 2030
*This prediction coupled with the Ricker ptarmigan populations
study suggests that in the area studied there might be a decline from 30
to 40 ptarmigans today to only 2 or 3 individuals by 2030!
What Does the Future Hold For
These Vertebrates?
While other species are able to migrate to
higher elevation in response to climate
change, these species can only move so high
before they run out of room
A warming of 3 degrees centigrade over
the next century will wipe out 80% of
alpine islands, and extinguish a third to a
half of 613 alpine plants (Mark 03)
Conclusions
Alpine vertebrates are extremely susceptible to
the effects of global warming
There has been a decline in marmots, pikas,
and ptarmigans, since populations began to be
recorded
Alpine ecosystems can be used as a barometer
to study climate change
If the global warming trend continues, we could
see a loss in most or many alpine species
What Can Be Done To Prevent
These Species From
Disappearing?
 Retard the effects of global warming by switching to
clean renewable energy
 Promote more research on climate change
 Promote more research on alpine ecosystems
References
David W. Inouye et al.(2000) Climate change is affecting altitudinal
migrants and hibernating species.
Floyd, Ch.(2004) Marmot distribution and habitat associations in the
Great Basin.
Krajick, Kevin. (2004) All Downhill From Here?
Guiming Wang et al. (2002) Relationships between climate and
population dynamics of white-tailed ptarmigan in RMNP.
Brown, Paul. (2003) American pika doomed as ‘first mammal victim of
climate change.’
Beever, Erik. Latest census finds more American pika populations
disappear as climate warms.
Gellhorn, Joyce. (2003) Song of the Alpine
Baron, Jill S. (2003) Rocky Mountain Futures: An Ecological
Perspective