the American pika Chris Ray, CU

Ochotona princeps Ochotona princeps...and... habitat specialists herbivorous highly territorial hay-stackers...and... habitat specialists herbivorous highly territorial hay-stackers pikas are... related to rabbits as big as your fist non-hibernating highly vocal pikas are... related to rabbits as big as your fist non-hibernating highly vocal

Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas

Summer heat-stress Grinnell 1917 MacArthur & Wang 1973, 1974 Smith 1974 Hafner 1993, 1994 Hafner & Sullivan 1995 Verts & Carraway 1998 Li et al Simpson 2001 Beever et al. 2003, 2010 Summer heat-stress Grinnell 1917 MacArthur & Wang 1973, 1974 Smith 1974 Hafner 1993, 1994 Hafner & Sullivan 1995 Verts & Carraway 1998 Li et al Simpson 2001 Beever et al. 2003, 2010 Winter cold-stress Tapper 1973 Smith 1978 Morrison and Hik 2007 Beever et al & in prep. Winter cold-stress Tapper 1973 Smith 1978 Morrison and Hik 2007 Beever et al & in prep.

Shrinking distribution of the American pika

25 historical populations recorded (average date = 1933) 6 extinct by 1999 (►) 10 by 2008 (◄) Extinction rate is rising 25 historical populations recorded (average date = 1933) 6 extinct by 1999 (►) 10 by 2008 (◄) Extinction rate is rising

1999: 2,474 m 2008: 2,566 m 1933: 2,374 m >1 m/yr >10 m/yr Rising mean minimum elevation of 25 historical pika populations in the Great Basin Rising mean minimum elevation of 25 historical pika populations in the Great Basin Similar patterns in the Sierra Nevada (Moritz 2007) Similar patterns in the Sierra Nevada (Moritz 2007)

Habitat size/structure Human impacts Species interactions Thermal stress Habitat size/structure Human impacts Species interactions Thermal stress What predicts extinction? Beever et al. in press: Habitat area Accessibility Livestock grazing Acute heat-stress Chronic heat-stress Acute cold-stress Climatic refugium Beever et al. in press: Habitat area Accessibility Livestock grazing Acute heat-stress Chronic heat-stress Acute cold-stress Climatic refugium

Defining local extinction Persisting Transitional but persisting 200 m Extinct 3 km N = 11 N = 10 N = 4

“Habitat area” – amount within 0.8 km, or entire mtn range Candidate predictors of extinction: “Refuge” – elevation of highest habitat within 3 km 3 km

Candidate predictors of extinction (continued): “Accessibility” – distance to nearest non-4WD road “Grazing” – long-term use of the site by livestock “Acute heat stress” – number of days above 28°C/82°F “Chronic heat stress” – average summer temperature “Acute cold stress” – number of days below -10°C/14°F

Hourly haypile temperatures Joyce Gellhorn Temperature (C) Date (Month-Year)

3 stress metricsData usedHindcasts Acute heat-stress# days > 28 °C Σ >28, Δ >28, τ >28 Chronic heat-stressSummer mean T Σ μS, Δ μS, τ μS Acute cold-stress# days < -10* °C Σ <-10, Δ <-10, τ <-10 Hindcasting metrics of stress 3 data sets: Σ = long-term, Δ = climate change, τ = recent Study site T (°C)

What predicts extinction? Cold days (last 60 yrs) Cold days (last 60 yrs) Refuge (upslope habitat) Refuge (upslope habitat) Habitat area (w/in 0.8 km) Habitat area (w/in 0.8 km) Hot summer (recent mean) Hot summer (recent mean) Habitat area (w/in range) Habitat area (w/in range) Grazing Given the many factors that may be responsible for pika extinctions, perhaps the only reason our list of predictors looks like this is because we haven’t yet had the opportunity to consider other (perhaps better) predictors, and data from other regions.

Erb, Ray & Guralnick study, in prep. Of 69 historically occupied sites in the southern Rockies, only 4 are no longer occupied The 4 local extinctions are explained by moisture issues: pikas are missing only from the driest sites

How might climate cause extinction?

Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas

Gallatin Range Demographic Study Montana Ray

Gallatin Range Demographic Study Montana Ray

Gallatin Range Demographic Study Montana Ray

Gallatin Range Demographic Study Montana Ray

Gallatin Range Demographic Study Montana Ray

Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas Outline Motivation for an individual-based study of climatic stressors Preliminary results from a long-term study in Montana Preliminary results from a comparative study of MT & CO pikas

Bob Rapp Stress and survival study Gallatin Range, MT & Niwot Ridge, CO Ray et al.,

Stress and survival study Gallatin Range, MT & Niwot Ridge, CO Ray et al.,

Stress and survival study Gallatin Range, MT & Niwot Ridge, CO Ray et al.,

Stress and survival study Gallatin Range, MT & Niwot Ridge, CO Ray et al.,

Stress and survival study Gallatin Range, MT & Niwot Ridge, CO Ray et al.,

How might climate cause extinction? ? ? ? ? ? ?

How might climate cause extinction? Summer heat-stress Heat avoidance behavior Reduced foraging activity Smaller or inferior haypiles Winter cold-stress

How might climate cause extinction? Summer heat-stress Heat avoidance behavior Reduced foraging activity Smaller or inferior haypiles Winter cold-stress Smaller or inferior haypiles

Pika Haypile

How might climate cause extinction? Community interactions

Morning Late morning Noon Afternoon Automated camera at a marmot den Automated camera at a marmot den

How might climate cause extinction? Predation

How might climate cause extinction? Disease

What does the future hold? Manuscript in review, by Scott Loarie et al.* models local extinction probability according to climate for 97 resurveyed pika sites *S. Loarie, C. Field, C. Ray, E. Beever, P. Duffy, K. Hayhoe, J. Wilkening and J. Clark Mean annual temperature Decade (20 th century) I. Sierra II. Cascade III. Great Basin IV. Rocky Mtns

What does the future hold? Manuscript in review, by Scott Loarie et al.* models local extinction probability according to climate for 97 resurveyed pika sites *S. Loarie, C. Field, C. Ray, E. Beever, P. Duffy, K. Hayhoe, J. Wilkening and J. Clark Mean annual temperature Decade (20 th century) I. Sierra II. Cascade III. Great Basin IV. Rocky Mtns Mean annual temperature Projected Observed Mid-high emission scenarios Lower emission scenarios Moderate emission scenarios

Over 50% extinct by 2100? Probability of local extinction *S. Loarie, C. Field, C. Ray, E. Beever, P. Duffy, K. Hayhoe, J. Wilkening and J. Clark Predictions were conservative for the Great Basin

The End