A phenological examination
of terrestrial invertebrate
abundance, H. J. Andrews
Experimental Forest, OR
Kailan Mackereth
BioResource Research Program, Oregon State University
Judy Li, Ph.D
Fisheries and Wildlife, Oregon State University
Sherri Johnson, Ph.D
USFS Pacific Northwest Research Station, Oregon State University
What is phenology?
Study of cyclic and seasonal natural phenomena
http://en.wikipedia.org/wiki/Season
Climate Change
NOAA
Alan Vernon
James Gathany
AP Photo/U.S. Coast Guard, Petty Officer 2nd Class Kyle Niemi
Why Study Insects?
Physiology and behaviors regulated by
environment
Climate changes can alter insect:
• Locomotion
• Feeding
• Mating
• Oviposition
• Pupation
• Eclosion
Environmental Influences
• Photoperiod
– Day length
– June 21
– December 22
• Temperature
– Hot vs. Cold
– Period of warming or
chilling
Danks 1987
Photoperiod and Temperature
• Quiescence – response to environmental
conditions
– Hibernation
– Aestivation
• Diapause – programmed & determined
– Controlled by environmental factors
• Induction
• Termination
Insect Life Cycles
• Ametabolous
– No metamorphosis
• Hemimetabolous
– Incomplete
metamorphosis
• Holometabolous
– Complete metamorphosis
Variety of niches and habitats
Wikipedia.com
Biodiversity
Trophic
Structure
Niches &
Habitats
Biodiversity!
Life Cycle
Wilson, Edward Osborne, The Diversity Of Life,
(W. W. Norton & Company, 1993), p. 134.
Outcomes of phenological shifts
• Phenological decoupling
of interdependent
organisms
• Local extinction of
unadaptive species
©Doug Linton, Natural Resources Canada
• Proliferation of
adaptive species
http://www.fao.org/docrep/011/i0670e/i0670e02.htm
http://chuckpope.com/wp-content/uploads/2011/11/bee-1.jpg
© webmink
Objective
Investigate one season of terrestrial
invertebrate response to temperature and
corresponding elevational gradients at H. J.
Andrews Experimental Forest
H.J. Andrews
Phenology Core Sites
PC Sites
PC16
PC18
PC17
PC15
PC14
PC11
PC13
PC12
PC10
PC08
PC05
PC04 PC02
PC01
PC07
PC09
PC01
PC02
PC04
PC05
PC07
PC08
PC09
PC10
PC11
PC12
PC13
PC14
PC15
PC16
PC17
PC18
Elevation
(m.)
460
488
481
644
903
647
979
994
1116
1082
1178
965
971
1030
1301
1339
Forest
Stage
Young
Old
Young
Young
Old
Old
Old
Old
Young
Old
Old
Old
Old
Young
Old
Young
Max. Elevation: 1,627 m.
Min. Elevation: 411 m.
Hypothesis
Higher invertebrate abundance
will coincide with higher
temperatures attributed to
lower elevations
Methods
• Field
– 16 sites equipped with malaise
traps
– Samples every 6-9 days from
April 5, 2011 to July 12, 2011
– 172 samples were prepared for
laboratory analysis
• Laboratory
– Total Invertebrate Abundance
– Temperature data investigation
– Data accumulation and
organization
Total Insect Abundance
PC18
PC18
PC16
PC16
PC17
PC17
PC08
PC08
PC09
PC10
PC10
PC11
PC11
PC12
PC12
PC13
PC13
PC14
PC14
PC15
PC15
PC07
PC07
PC05
PC05
PC04
PC04
PC02
PC02
PC01
PC01
Total Insect Abundance
p-value < 0.05
Temperature Data
PC17 & PC18
PC09, PC16,
PC17, PC18
Cluster Analysis 1
Average Daily Temperatures per Site
October 20, 2010 through June 12, 2011
Information Remaining (%)
100
75
50
25
PC01
Avg1
PC04
Avg4
PC02
Avg2
PC05
Avg5
PC08
Avg8
Avg7
PC07
PC10
Avg10
PC14
Avg14
PC15
Avg15
PC09
Avg9
PC11
Avg11
PC12
Avg12
PC16
Avg16
PC13
Avg13
PC17
Avg17
PC18
Avg18
High Temperature
Mid Temperature
Low Temperature
0
Cluster Analysis 2
Average Daily Temperatures per Site
July 16, 2010 through October 20, 2011
Information Remaining (%)
100
75
50
25
PC01
Avg1
PC04
Avg4
PC08
Avg8
PC02
Avg2
PC05
Avg5
PC07
Avg7
PC14
Avg14
PC15
Avg15
PC10
Avg10
PC11
Avg11
PC12
Avg12
PC16
Avg16
PC09
Avg9
PC13
Avg13
PC17
Avg17
PC18
Avg18
High Temperature
Mid Temperature
Low Temperature
0
Temperature Groups
Significant differences in Total Insect
Abundance between Temperature Groups
p-value < 0.05
n = 29
n = 68
n = 65
Cumulative Insect Abundance
+6,286
4,073
2,213
Cumulative Degree Days, Forest
Growth, and Total Insect Abundance
PC08
PC01
Significant differences in Total Insect
Abundance between Forest Types
p-value < 0.05
n = 94
n = 68
Summary
Greatest abundance occurred at mid
temperature sites
PC16
PC18
PC17
PC15
PC14
PC11
PC13
PC12
PC10
PC08
PC05
PC04 PC02
PC01
PC07
PC09
Conclusions
• Invertebrate abundance
or activity depends on
many variables, such as:
– Temperature
– Altitude
– Food Supply
– Hydroperiod
– Aspect/Slope
– Precipitation/Humidity
– Photoperiod
Future Research
• Determine species diversity in
samples
– Species richness
– Evenness
• Compare diversity across sites
• Incorporate site specific
variables
– Slope
– Aspect
• Incorporate vegetation and
forest growth
Future Research
“Climate is the average weather in a given place,
usually over a period of 30 years.” - EPA
Incorporate multiple years of data into one
study
– Currently have insect data from 2009-2011
– Climate and ecological data extending back to
late 1940s
Questions?
Gratitude
•
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Judy Li, Sherri Johnson, and Bill Gerth
Jay Sexton and Mark Schultz
U.S. Forest Service – Pacific Northwest Research Station
The Stream Ecology Lab of Nash Hall, OSU
BioResource Research Program