Missouri bladderpod Lesquerella filiformis Rollins

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Missouri bladderpodLesquerella filiformis Rollins
photo NPS archive
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(No Transcript)
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Missouri bladderpod

• listed Federally Endangered in 1987
• narrow endemic - 62 populations in 5 counties of
  sw Missouri and nw Arkansas
• threatened by habitat alteration and development
• winter annual - germinates in fall, flowers the
  following spring
• population size fluctuates from year to year
  (some years none survive)

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Local concerns

• five populations at WICR
• encroaching woody vegetation due to fire
  supression
• exotic species establishment
• largest population at a site of great historical
  significance
• how to manage for species and interpretive value
  simultaneously?

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Monitoring objectives

• How does abundance fluctuate over time?
• annual abundance estimates
• Which factors are driving abundance changes?
• weather data correlated with abundance
• demographics sampling, habitat correlates
• How is limestone glade habitat changing?
• vegetation transects

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Abundance estimates

• Stratified random sampling
• data since 1988
• Grid-based census
• developed during protocol design
• data for 1997 - 1998
• Adaptive cluster sampling
• simultaneous with protocol development
• data for 1999 - 2001

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Stratified random sampling
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Stratified random sampling

• 3 meter x 3 meter quadrats
• spatially stratified across core area of the
  population
• sample size of 31- 77 quadrats
• tally all individuals within the quadrat,
  subsample for number of stems and fruits per
  individual

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Missouri bladderpod abundance
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Grid-based census

• sampling grid covers entire glade, including
  unoccupied edge areas
• visit every 5 x 5 meter grid cell
• estimate number of individuals in each cell
  (log-scaled categories)
• periodic calibration by counting all individuals
  after estimating
• simultaneous collection of habitat data for each
  grid cell

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Grid-based census
Annual brome
Red cedar
Missouri bladderpod
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Grid-based census
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Grid-based census

• directional error - consistent underestimation
• only tested in years of low abundance

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Adaptive cluster sampling

• based on sampling grid, divided into primary
  units and secondary units (3 x 3 meters)
• subset of primary units selected, random draw to
  select seed cell
• if number of plants in seed cell gt 9, adaptive
  sampling initiated in adjacent cells
• record tally of individuals and habitat attribute
  data for each secondary unit sampled

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Sampling grid for Missouri bladderpod
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Stratified Random Sampling
Two-Stage Adaptive Sampling
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Methods comparison
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Solution?

• reduction of variance
• confidence in abundance estimates
• comprehensive snapshot of spatial abundance
  patterns
• ability to map and monitor changes in core
  habitat

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Missouri bladderpod implementation schedule
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Demographic monitoring
photo K. Mlekush
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Demographic monitoring
photo K. Mlekush
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Understanding Missouri bladderpod life cycle
viability
Seed bank
germination
reproduction
Mature plants
Germinated seedlings
survival growth
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Most transition rates depend on microhabitat
viability
Seed bank
germination
reproduction
Microhabitat
Mature plants
Germinated seedlings
survival growth
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L. filiformis habitat is variable at small scales
photo K. Mlekush
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Survival rates by habitat type
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Freeze-thaw cycles
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Fecundity by microhabitat
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Seed production by microhabitat
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Seed replacement by microhabitat
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Estimated geometric loss of seed viability
data source Thomas and Jackson 1990
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Unfinished business

• solidify the abundance estimate methods, apply to
  smaller populations
• improved synthesis and reporting