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Breeding birds during 50 years of post- fire succession in the Sierra Nevada Martin G. Raphael, Daniel A. Airola, Gary A. Falxa, Roger D. Harris, and Peter A. Stine
Breeding birds during 50 years of post-fire succession in the Sierra Nevada
Martin G. Raphael, Daniel A. Airola, Gary A. Falxa, Roger D. Harris, and Peter A. Stine
1960 - The Donner Fire burned ~18,000 ha on the eastern Sierra
Nevada
1965 – two 8.5-ha permanentplots established
Burned Plot
Unburned Plot
Objectives
Examine and contrast changes in vegetation over ~50-yr time series
Estimate bird abundance and diversity and compare results on burned and unburned plots over 50-yr
Relate changes in bird community to changes in vegetation
Monitoring timeline
Donner
fire
1966-68
1975-79
1981-85
2010-14
1960 1970 1980 1990 2000 2010
Burned plot has changed dramatically over time
(no management or harvest)
1965 2012
Field equipment (and people) have changed too
1965 2012
Density of Snags(number > 38 cm/ha)
1968 1975 1983 20120
5
10
15
20
25
30
35
BurnedUnburned
Percent Cover, Shrubs(n = 1170 points)
1975 1983 20110
10
20
30
40
50
60
70
80
BurnedUnburned
Herbs & Grasses(% cover, n = 1170 points)
1975 1983 20110
10
20
30
40
50
60
70
BurnedUnburned
Basal Area of Conifers(m2/ha)
1975 1983 20110
10
20
30
40
50
60
1975 1983 20110
10
20
30
40
50
60
Other
White fir
Yellow pine
Burned Unburned
Conifer Canopy Cover(%, n = 1170)
Burned Unburned0
10
20
30
40
50
60
70
80
90
19752011
Total Bird Territories
1960 1970 1980 1990 2000 2010 20200
10
20
30
40
50UnburnedBurned
Species Richness
1960 1970 1980 1990 2000 2010 20200
5
10
15
20
25
30
Un-burned
Foraging guilds
Wood excavating (woodpeckers) Bark gleaning (nuthatches, brown
creeper) Flycatching (nighthawk, flycatchers) Canopy foliage searching (jays,
chickadees, kinglets, vireos, warblers) Ground/brush searching (quail,
dove, hummingbirds, bluebird, solitaire, thrush, robin, towhee, juncos, finches, sparrows)
Wood Excavating
Bark gleaning
Flycatching
Canopy Foliage Searching
Ground/brush Searching
Percent Similarity(Ruzicka’s Index)
1966-68
1975-79
1981-85
2010-14
0
10
20
30
40
50
60
Burned vs Unburned
Burned Unburned0
10
20
30
40
50
60
1966-68 vs 2010-14
Major Changes in Species Abundance
IncreasedSpecies 1960s 2010s
Hermit warbler
Absent Common
Pileated woodpecker
Common raven
Osprey
Northern goshawk
Absent Rare
Clark’s nutcracker
Black-throated gray warbler
Green-tailed towhee
DecreasedSpecies 1960s 2010s
Mountain bluebird
Common Absent
Brewer’s sparrow
Cooper’s hawk
Sooty grouse Moderate Absent
House wren
Pygmy nuthatch
American kestrel
Lazuli bunting
Rare Absent
Lewis’ woodpecker
Temperature has increased over time
Summary
Vegetation is still changing, 50 years after fire on the burned plot, but also on the unburned plot
Bird community structure (guilds and species represented) has changed dramatically on the burned plot in response to vegetation change
The bird community on the unburned plot has also changed, to a smaller degree
Overall species richness has been comparable on plots over time
Bird abundance (# territories) has increased by roughly 50% on both plots
Some bird population changes could be due to climate change
Thanks to
Sagehen Creek Field Station for accommodation and logistics
Station managers Jeff Brown and Faerthen Felix for help and advice
Carl and Jane Bock for initiating this work and suggesting our recent follow-up surveys
Meryl Sundove and Joe Batres for field assistance
Truckee Ranger District for protecting plots Pacific Northwest and Pacific Southwest
Research Stations for funding
