Variability in microclimates of mountain ranges
of western North America, and its effect on
distribution and trend of alpine mammals
U.S. Department of the Interior
U.S. Geological Survey
MTNCLIM: Oct 2012
Variability in microclimates of mountain ranges
of western North America, and its effect on
distribution and trend of alpine mammals
Erik A. Beever, USGS Northern Rocky Mtn. Science Center
Solomon Dobrowski, College of Forestry & Cons., Univ. of MT
Nifer Wilkening, Ecol. & Evol. Biology, Univ. of CO
Embere Hall, TSS & Wyoming Coop. Fish and Wildlife
Research Unit, Univ. of WY
Sue Wolff, Grand Teton NP, National Park Service
U.S. Department of the Interior
U.S. Geological Survey
MTNCLIM: Oct 2012
Road map: Key themes
Heterogeneity: climate, biotas, interaction
Hypotheses driven by mechanisms
Importance of context (GB, PIP, GYE)
Vulnerability vs. adaptive plasticity
Modeling changes in species distributions:
spatial heterogeneity in amount of climate changes
MTNCLIM: Oct 2012
Patterns of climate, for widely-distributed spp.
Large/continental scale
Coastal to continental gradients, jet stream
AO, ENSO, NAO
Latitudinal gradients
Meso-scale
Elevational lapse rates
Windward/leeward PPT
Small-scale patterns
Aspect (insolation)
Association w/ water
RIFs, caves, lava tubes
Cold-air pooling, inversions
from Ray et al. 2010
MTNCLIM: Oct 2012
Pikas as model sp. for ecological-niche testing
Locally abundant; rare 4 mammals
Relatively stable population sizes
Highly detectable (haypiles, calls)
Monitoring, research are less expensive
Photo: S. Weber
Easily defined habitat, NOT
changing over time
losses not confounded by habitat change
HSTal records & 15 yrs of recent
data indicate a changing distribution
Photo: S. Weber
MTNCLIM: Oct 2012
Pikas as model sp. for ecological-niche testing
Locally abundant; rare 4 mammals
Relatively stable population sizes
Highly detectable (haypiles, calls)
Monitoring, research are less expensive
Photo: S. Weber
Easily defined habitat, NOT
changing over time
losses not confounded by habitat change
HSTal records & 15 yrs of recent
data indicate a changing distribution
Photo: S. Weber
MTNCLIM: Oct 2012
Pikas as model sp. for ecological-niche testing
Locally abundant; rare 4 mammals
Relatively stable population sizes
Highly detectable (haypiles, calls)
Monitoring, research are less expensive
Photo: S. Weber
Easily defined habitat, NOT
changing over time
losses not confounded by habitat change
HSTal records & 15 yrs of recent
data indicate a changing distribution
Photo: S. Weber
MTNCLIM: Oct 2012
Pikas as model sp. for ecological-niche testing
Locally abundant; rare 4 mammals
Relatively stable population sizes
Highly detectable (haypiles, calls)
Monitoring, research are less expensive
Photo: S. Weber
Easily defined habitat, NOT
changing over time
losses not confounded by habitat change
HSTal records & 15 yrs of recent
data indicate a changing distribution
Photo: S. Weber
MTNCLIM: Oct 2012
Pikas as model sp. for ecological-niche testing
Locally abundant; rare 4 mammals
Relatively stable population sizes
Highly detectable (haypiles, calls)
Monitoring, research are less expensive
Photo: S. Weber
Easily defined habitat, NOT
changing over time
losses not confounded by habitat change
HSTal records & 19 yrs of recent
data indicate a changing distribution
Photo: S. Weber
MTNCLIM: Oct 2012
Greenmonster Cnyn., Monitor Range, central NV
last stronghold within site; loc’n of type specimen
Photo: S. Weber
MTNCLIM: Oct 2012
Questions  Hypotheses
Have there been any distributional
changes since historical specimen
records?
What combination of factors was
responsible for changes (if any)?
Did the pace and drivers of losses differ
between 20th Century and last decade?
Across broad domains, is pattern of
site-level losses best predicted by
magnitude of change in climatic
attributes, or by relative status of
climatic attributes?
Photo: J. Jacobson
Photo: J. Jacobson
Questions  Hypotheses
Have there been any distributional
changes since historical specimen
records?
What combination of factors was/is
responsible for changes, patterns?
Did the pace and drivers of losses differ
between 20th Century and last decade?
Across broad domains, is pattern of
site-level losses best predicted by
magnitude of change in climatic
attributes, or by relative status of
climatic attributes?
Photo: J. Jacobson
Photo: J. Jacobson
Questions  Hypotheses
Have there been any distributional
changes since historical specimen
records?
What combination of factors was
responsible for changes (if any)?
How do distributional controls vary,
spatially and temporally?
Across broad domains, is pattern of
site-level losses best predicted by
magnitude of change in climatic
attributes, or by relative status of
climatic attributes?
Photo: J. Jacobson
Photo: J. Jacobson
Study sites
within the Great Basin
Beever et al. 2011
(blue areas: >2,286 m)
Population recently discovered
Population extirpated during 20th century (i.e., by 1999)
Extant population, as of 2008
Population extirpated since 1999 (i.e., after 1990s sampling)
3 periods of sampling
{
{
Historic
1898-1956
Recent_1
1994-1999
Recent_2
2003-2008
MTNCLIM: Oct 2012
Anatomy of a decline: persistence
6 local extinctions from historic
to end of my 1st sampling (once
every 10.7 yrs)
4 add’l local extinctions from
1st to end of my 2nd sampling
(once every 2.2 yrs)
S. Weber
Old evidences
N = 25 historical
locations
Beever et al. 2011
3 periods of sampling
{
{
Historic
1898-1956
Recent_1
1994-1999
Recent_2
2003-2008
Anatomy of a decline: upslope migrations
Beever et al. 2011
Minimum elevation of detections, Historic to my
first (1990s) sampling: 13.2 m per decade
Minimum elev. of detections, 1st to 2nd sampling:
145.1 m per decade
Parmesan & Yohe (2003) meta-analysis: 6.1 m per decade
Chen et al. (2011) meta-analysis: 11.0
2008 min: 2,588 m
m per decade
No ∆ in max, mean, or median elev, at most sites
At lower-elevation margins, apparent: a) loss of
animals on S-facing slopes, and b) reduced animal
densities
Krajick (2004), Science
1999 min: 2,461 m
Historic min: 2,366 m
S. Weber
Potential mechanisms of GCC on montane spp.:
summer heat stress
Pika-occupied sites
rarely had withintalus temps above
pika-lethal thresholds
Beever et al. 2010, Ecol. Appl.
Locally-extinct sites
more often had
within-talus temps
above pika-lethal
thresholds
Potential mechanisms of GCC on montane spp.:
winter cold stress (cont’d.)
Most pikaoccupied sites
snow-covered 0.5
– 8.2 months/yr
Beever et al. 2010, Ecol. Appl.
8 of 10 locally
extinct sites never
had snow cover
>2 weeks
Different drivers of extirpation? (b)
Ranks of variable weights shifted dramatically,
last decade vs. during 20th Century
Beever et al. 2011, GCBiol.

MTNCLIM: Oct 2012
Different drivers of Popul’n Size?

Compare variable weights from same model
Beever et al., in revision
suite for #indiv’s detected
2000s surveys, n = 16 sites
1990s surveys, n = 19 sites
#
models
wi
wi / model
Grazed?
7
0.7509
0.107
Pika-Equiv. Elev
9
0.723
PPT
9
GrazIntensity
Amt of Habitat
Predictor
#
models
wi
wi / model
PPT
9
0.826
0.092
0.080
GrazIntensity
5
0.2874
0.057
0.3621
0.040
Pika-Equiv. Elev
9
0.4246
0.047
5
0.1016
0.020
Amt of Habitat
9
0.1374
0.015
9
0.1685
0.019
Grazed?
7
0.0912
0.013
Predictor
MTNCLIM: Oct 2012
Different drivers of Popul’n Size?

Compare variable weights from same model
Beever et al., in revision
suite for #indiv’s detected
2000s surveys, n = 16 sites
1990s surveys, n = 19 sites
#
models
wi
wi / model
Grazed?
7
0.7509
0.107
Pika-Equiv. Elev
9
0.723
PPT
9
GrazIntensity
Amt of Habitat
Predictor
#
models
wi
wi / model
PPT
9
0.826
0.092
0.080
GrazIntensity
5
0.2874
0.057
0.3621
0.040
Pika-Equiv. Elev
9
0.4246
0.047
5
0.1016
0.020
Amt of Habitat
9
0.1374
0.015
9
0.1685
0.019
Grazed?
7
0.0912
0.013
Predictor
MTNCLIM: Oct 2012
Another part of climate …
Investigating importance of various climatic
water-balance metrics
Dobrowski et al., in press
AET
Deficit
GS-PPT
Max. SWE
MTNCLIM: Oct 2012
Drivers of Recent pika density?
2000s surveys, n = 16 sites

Water-balance metrics more predictive of pika
density than are temp-based metrics
Beever et al., in revision
AICc
∆AICc
K
Akaike
weight
Cumulative
weight
Model r2
Maximum SWE + Latitude
126.13
0.00
4
0.301
0.301
0.601
GS-precipitation + Latitude
128.15
2.02
4
0.110
0.411
0.551
AvgSummT + Latitude
128.78
2.65
4
0.080
0.491
0.534
Maximum SWE
128.96
2.83
3
0.073
0.564
0.438
Latitude
129.34
3.21
3
0.061
0.625
0.425
Maximum SWE + MaxElevR + Latitude
129.39
3.25
5
0.059
0.684
0.606
Null
136.17
10.04
2
0.002
0.994
Model
MTNCLIM: Oct 2012
Drivers of Recent pika density?
2000s surveys, n = 16 sites

Water-balance metrics more predictive of pika
density than are temp-based metrics Beever et al., in revision
Variable
weight
Weight per
model
Sign of variable
coefficients
Maximum SWE
0.471
0.0941
Positive
Latitude
0.802
0.0501
Positive
Growing-season precipitation
0.159
0.0396
Positive
Average Summer temperature
0.117
0.0195
Negative
Average annual precipitation
0.064
0.0160
Positive
Residual of maximum local-habitat elevation on latitude
0.150
0.0107
Mixed
Grazed in most years before 2000s sampling?
0.034
0.0085
Negative
Days below -5°C
0.033
0.0082
Negative
Water deficit
0.040
0.0079
Negative
Days above 28°C
0.018
0.0058
Positive
Actual evapotranspiration
0.028
0.0056
Mixed
Variable
MTNCLIM: Oct 2012
2012 Results (Great Basin)
n = 10 sites

DROUGHT, after
2010-11 heavy winter
MTNCLIM: Oct 2012
2012 Results (Great Basin)
n = 10 sites

Geometric mean # animals detected was 55% of
# detected in 2003-2008 and 48% of 1990s # of
detections

Failed to detect pikas at ‘new’ historical site
(1930s)

Lower bound: 2 downslope migra’ns, 1 upslope

∆ in PopSize partly reflects climatic water-balance

Tension between long- and short-term conditions
MTNCLIM: Oct 2012
Assessments of pika vulnerability:
occurrence, distrib. patterns, hab. assoc’ns
Pikas in Peril
Greater Yellowstone Initiative
Continental-scale sampling
8 National Parks
Ecosystem-scale sampling
5 National Forest Units
2 National Parks
Objectives …
Courtesy of Sue Wolff, NPS
MTNCLIM: Oct 2012
Assessments of pika vulnerability:
occurrence, distrib. patterns, hab. assoc’ns
Pikas in Peril
Greater Yellowstone Initiative
Continental-scale sampling
8 National Parks
Ecosystem-scale sampling
5 National Forest Units
2 National Parks
Document occurrence patterns, predict distribution across each of the 2 domains
Measure gene flow, model connectivity of pika populations across
major genetic subdivisions and habitat types
C. Epps
Project climate-change effects on the
future distribution, connectivity and
vulnerability of pika populations in
each domain
Targeted for Genetic Studies
MTNCLIM: Oct 2012
2010, 2011 percent pika occupancy
in 8 PIP NPS units
54, 34%
97
65, 63%
252
339
45, 48%
21, 7%
201
70
24, 29%
225
15, 42%
Average
occupancy:
45, 40%
75
1330
67, 43%
71
71, 44%
MTNCLIM: Oct 2012
Grand Teton NP: 2092-3625m
Crater Lake NP: 1170-2430m
4
3
3
2011
2010
Strata
Strata
4
2
2
1
1
0
0.2
0.4
0.6
0.8
1
0
0.2
0.4
Proportion occupied
0.6
0.8
Proportion occupied
Yellowstone NP: 1636-2936m
Lassen Volcanic NP: 1840-3091m
4
3
2011
2010
Strata
Strata
3
2
2
1
1
0
0.05
0.1
0.15
0.2
Proportion occupied
0.25
0.3
0
0.2
0.4
0.6
Proportion occupied
0.8
MTNCLIM: Oct 2012
38, 51%
35, 32%
55, 34%
2010, 2011
occupancy
survey
results
for the GYE
45, 48%
48, 96%
74, 82%
53, 43%
Average: 44%, 55%
Proportion Occupied in the GYE
by Strata: 2010
n=40
Stratum 4: >3,276
n=94
Stratum 3: 2,861-3,275
n=136
Stratum 2: 2,446-2860
n=100
Stratum 1: 2,210-2,445
n=32
Stratum 0: <2,2029
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
MTNCLIM: Oct 2012
Behavioral plasticity softening boundaries
Optimal body shape for conserving heat, when cold
vs.
J. Jacobson
J. Jacobson
Frequency differs dramatically
MTNCLIM: Oct 2012
Behavioral plasticity softening boundaries
Haypiles in unexpected locations
under tree branches
in downed logs
standing-dead trees
slash piles
river riprap
lakesides, below
high-water level
Paired T sensors
deployed 2010-2012, to
quantify microclimates
A. Loosen
Behavioral plasticity: empirical examples
Cold season (1 Oct-31 May), GYE
• (Downed Log T) - (Ambient T)
Warmer in downed log, but
not significantly so
Mean difference = 0.00 °C
95% CI: -0.0966 to 0.1051, p = 0.9340
A. Loosen
• (Talus T) - (Downed Log T)
Warmer in downed log
Mean difference = -0.14°C
95% CI : -0.2544 to -0.0304,
p=0.0128
•
No appreciable difference in warm season
A. Loosen
Behavioral plasticity: empirical examples
Cold season (1 Oct-31 May), GYE
• (Standing dead T) - (Ambient T)
Warmer inside standing
dead tree
Haypile
Mean difference = 0.94°C
95% CI: 0.86 to 1.03°C; p < 0.001
• (Standing dead T) - (Talus T)
Warmer inside standing
dead tree
Mean difference = 1.73°C
95% CI : 1.54 to 1.91°C; p<0.001
•
A. Loosen
No appreciable difference in warm season
MTNCLIM: Oct 2012
Most-protected lands are mostly mountainous
Lt. green
Purple
 72% of strictest-conservation
federally managed lands are
mountainous
 9.9% of non-mountainous landscapes
are federally managed under
strictest conservation
11 western U.S. states
(PADUS) v1.1 data
Fed = USFS + DOI lands
Non-fed = all other lands
Mountainous = Categories C5, C6, & D3-6 from
Hammond’s (1970) classes of land-surface form
MTNCLIM: Oct 2012
Thanks !
Field assistance
S. Weber
J. Fontaine
D. Wright
K. Scully
J. Landmesser
S. Shaff
R. Beever
Y. Yano
Misc. other
P. Brussard M. Peacock
T. Lawlor
M. Huso
W. Simpson B.J. Verts
D. Grayson J. Lawler
A.T. Smith
C. Millar
J. Patton
MTNCLIM: Oct 2012
Evidence of climatic influence on pikas
EXPERIMENTAL: Vulnerability to
direct heat stress
(Smith 1974)
Hotter, drier macroclimates at
extirpated vs. extant sites
PRISM-modeled data, AND iButtons in taluses
across Basin
iButton field data, 2005-2006
# Days > 28˚C
Avg summer
temperature (˚C)
# Days < 0˚C
# Days < -5˚C
Pika-extant sites (N = 15 sites)
2.8 + 1.0
12.05 + 1.01
204.4 + 13.2
15.0 + 4.6
Pika-extirpated sites (N = 10)
10.9 + 4.0
17.02 + 0.72
159.6 + 9.7
28.7 + 7.8
Beever et al. 2010, Ecol. Appl.
MTNCLIM: Oct 2012
Elevation Ranges
(m)
Nat’l Forests
(m)
Crater Lake NP
1170-2429
Bridger-Teton NF
1767-3217
Craters of the Moon NM
1511-1833
Caribou-Targhee NF
1767-3116
Grand Teton NP
2092-3635
Custer NF
1800-3246
Greater Sand Dunes NP
2811-3832
Gallatin NF
1800-3000
Lassen Volcanic NP
1840-3091
Shoshone NF
1998-3691
Lava Beds NM
1249-1717
Rocky Mtn NP
2572-3795
Overall Range
1170-3830 m
Yellowstone NP
1636-2936
NPS units
MTNCLIM: Oct 2012