Interactions between Avian and Insect Herbivore Communities within MOFEP

Transcription

1 Interactions between Avian and Insect Herbivore Communities within MOFEP John Landosky, Robert J. Marquis, Rick Clawson, Wendy Gram, Paul Porneluzi, John Faaborg, Julie Ryan, Florence DiTirro, Rebecca Forkner, John Lill, and Josiane Le Corff University of Missouri St. Louis November 8, 27

2 Outline What is MOFEP? Insect and avian communities interactions? Preliminary analysis: Something there? Refining the analysis

3 What is MOFEP?

4 MOFEP What s the best way to harvest timber while conserving healthy ecosystems?

5 Design

6 Timeline 1996: Treatment applied Proposed 211 treatment : Post-treatment data gathered (full-scale) Post-treatment : Baseline data gathered (full-scale) Pre-treatment : Baseline data gathered (preliminary)

7 Timeline 1996: Treatment applied 1997-present Proposed 211 treatment : Post-treatment data gathered (full-scale) Post-treatment : Baseline data gathered (full-scale) Pre-treatment : Baseline data gathered (preliminary)

8 Isa textula (Limacodidae) Ecosystem health?

9 Avian/Insect Interactions

10 Top-Down/Bottom-Up Interactions Do trophic levels interact? Top-down? Bottom-up? How can we test for interactions with our data?

11 Bird Project Hypothetical HypotheticalWOTH WOTHObservations: Observations: June 2, 27 June 9, 27 June 18, 27 Crew center of WOTH territory *** members cover entire forest using birdlines Identify singing males and spot-map Each line walked 1 times during the month of June Three independent observations define a bird territory

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14 Bird Census

15 Common MOFEP Species Common Name Scientific Name Forest Interior Acadian fly catcher Empidonax virescens Kentucky warbler Oporornis formosus Ovenbird Seiurus aurocapilla Worm-eating warbler Helmitheros vermivorum Wood thrush Hylocichla mustelina Red-eyed vireo Vireo olivaceus Early Sucessional Indigo bunting Passerina cyanea Prairie warbler Dendroica discolor Hooded warbler Wilsonia citrina Yellow-breasted chat Icteria virens White-eyed vireo Vireo griseus Black-and-white warbler Mniotilta varia

16 Insect Project Leaf chewing herbivores on White oak Quercus alba Black oak Quercus velutina Four times per year Early May, and late June, July, and August Over 25 species identified

17 Free Feeders vs. Shelter Builders Shelter Builders Free Feeders

18 Bird Census??

19 Preliminary Analysis Is there something there?

20 Preliminary Analysis Model Bird Census

21 Preliminary Analysis Model Bird territory size 2m from center Bird Census

22 Preliminary Analysis Model Bird territory size 2m from center Bird Effect Sum each species # of territories Mating pair weight Bird Census

23 Preliminary Analysis Model Bird territory size 2m from center Bird Effect Sum each species # of territories Mating pair weight Insect stands point in space Bird Census

24 Preliminary Analysis Model Bird territory size 2m from center Bird Effect Sum each species # of territories Mating pair weight Insect stands point in space If >5% coverage corrected If <5% coverage excluded Bird Census

25 Hypothetical Data Slide Pre-treatment ( ) yy==-.12x -.12x rr2 2== Compound CompoundSymmetry Symmetry Year: Year:pp<<.1.1 Ecotype: p=.1 Ecotype: p=.1 Bird Density Bird Density(cov): (cov):p=.2 p=.2 Top-Down.8 Post-treatment (1997-2) yy==-.21x -.21x rr2 2== Herbivore Abundance (residuals) Herbivore Abundance (residuals) Unstructured Unstructured Year: Year:pp<<.1.1 Ecotype: p=.34 Ecotype: p=.34 Treatment: Treatment:p=.23 p=.23 Bird Density (cov): Bird Density (cov):p=.1 p=.1 Top-Down 15 Birds w/in 2m 3 15 Birds w/in 2m 3

26 Hypothetical Data Slide Pre-treatment ( ) yy==.23x.23x rr2 2== Compound CompoundSymmetry Symmetry Year: Year:pp<<.1.1 Ecotype: p=.1 Ecotype: p=.1 Bird Density Bird Density(cov): (cov):p=.2 p=.2 Bottom-Up Bottom-Up.8 Herbivore Abundance (residuals) -.8 Post-treatment (1997-2) yy==.31x.31x rr2 2== Unstructured Unstructured Year: Year:pp<<.1.1 Ecotype: p=.34 Ecotype: p=.34 Treatment: Treatment:p=.23 p=.23 Bird Density (cov): Bird Density (cov):p=.1 p=.1.8 Bottom-Up Bottom-Up Herbivore Abundance (residuals) 15 Birds w/in 2m Birds w/in 2m 3

27 Effect of Bird Density on Herbivore Abundance Pre-treatment ( ) Unstructured Unstructured Square-root Square-roottransformed transformed Year: p < Year: p <.1.1 Ecotype: p=.728 Ecotype: p=.728 Bird Density Bird Density(cov): (cov):p=.43 p= Post-treatment (1997-2) yy==-.15x -.15x rr2 2== First Order First OrderAutoregressive Autoregressive Year: Year:pp<<.1.1 Ecotype: p=.56 Ecotype: p=.56 Treatment: Treatment:p=.311 p=.311 Bird Density (cov): Bird Density (cov):p=.61 p=.61.6 Herbivore Abundance (residuals) Herbivore Abundance (residuals) Birds w/in 2m 3 15 Birds w/in 2m 3

28 Effect of Bird Density on Free Feeder Herbivore Abundance Pre-treatment ( ) yy==-.66x -.66x rr=2= First Order First OrderAutoregressive Autoregressive Year: Year:pp<<.1.1 Ecotype: p=.1 Ecotype: p=.1 Bird Density Bird Density(cov): (cov):p=.67 p=.67.8 Post-treatment (1997-2) yy==-.58x -.58x rr2 2== Compound CompoundSymmetry Symmetry Year: Year:pp<<.1.1 Ecotype: p=.12 Ecotype: p=.12 Treatment: Treatment:p=.36 p=.36 Bird Density (cov): Bird Density (cov):p=.26 p=.26.8 Free Feeder Abundance (residuals) Free Feeder Abundance (residuals) Birds w/in 2m 3 15 Birds w/in 2m 3

29 Effect of Bird Density on Ratio of Free Feeders to Shelter Builders Pre-treatment ( ) yy==-.17x -.17x rr2 2== First Order First OrderAutoregressive Autoregressive Year: Year:pp== Ecotype: p <.1 Ecotype: p <.1 Bird Density Bird Density(cov): (cov):p=.43 p=.43 Bird Density * Year = Bird Density * Year = ANCOVA ANCOVA Ecotype: Ecotype:pp== Bird Density (cov): Bird Density (cov):pp== Ratio free feeders to shelter builders (residuals) Birds w/in 2m 3 ANCOVA ANCOVA Ecotype: Ecotype:pp <<.1.1 Bird Density (cov): Bird Density (cov):pp==.1.1 yy==-.1926x x.4363 ANCOVA ANCOVA Ecotype: Ecotype:pp==.1.1 Bird Density (cov): Bird Density (cov):pp== yy==-.1339x x.262

30 Effect of Bird Density on Ratio of Free Feeders to Shelter Builders Post-treatment (1997-2) yy==-.59x -.59x rr2 2== Compound 1997 CompoundSymmetry Symmetry ANCOVA ANCOVA ANCOVA ANCOVA Year: Year:pp<<.1.1 Ecotype: Ecotype: Ecotype:pp== Ecotype:p=.15 p=.15 Ecotype: Ecotype:pp== Treatment: p=.966 Treatment: p=.229 Treatment: p=.966 Treatment: p=.229 Treatment: p =.1 Treatment: p =.1 Bird Density (cov): p<.1 Bird BirdDensity Density(cov): (cov):p=.11 p=.11 Bird Density (cov): p<.1 Bird BirdDensity Density(cov): (cov):p=.671 p=.671 yy== Bird Density * Year = Bird Density * Year =.4.8 Ratio free feeders to shelter builders (residuals) Birds w/in 2m ANCOVA ANCOVA ANCOVA ANCOVA Ecotype: Ecotype: Ecotype:pp== Ecotype:pp== Treatment: p =.63 Treatment: p =.875 Treatment: p =.63 Treatment: p =.875 Bird Density (cov): p=.539 Bird Density (cov): p=.543 Bird Density (cov): p=.543 Bird Density (cov): p=.539

31 Preliminary Conclusions All herbivores considered together no relationship between insects and birds Just free feeders Some evidence for negative correlation between insects and birds Ratio of free feeders to shelter builders Birds shift herbivore community structure in some years but not others

32 Refining the Model Under construction

33 Territory: From Point to Area A challenge Preliminary analysis crude Conspecifics defend territories Territory size may depend on Bird species Topography Region (i.e. Ozark highlands) Year Territories may not be circular = center of territory = modeled territory

34 Territory: From Point to Area Euclidean polygons ½ distance to nearest conspecific in 36 degrees Maximum mean distance to nearest conspecific/2 + 1 SD Limit territory by topography

35 Insect Stand: From Point to Distribution Stands distributed in space Stand as point can be inaccurate misleading Abundance best by stand Predation pressure per tree summed across trees to stand

36 Diet and Foraging

37 Summary Preliminary evidence for top-down effects of birds on insects Working with authors to make the model more biologically relevant Territory size Diet and foraging behaviors

38 Acknowledgments Kathleen Baker Herbivore crews Bird crews Randy Jensen Missouri Department of Conservation Marquis Lab