Insights from community ecology into the role of enemy release in causing invasion success: the importance of native enemy effects
Biological Invasions
Kirsten M. Prior1, Thomas H.Q. Powell, Ashley L. Joseph, Jessica J. Hellmann
Corresponding Author1: University of Florida; priorkm@gmail.com
Electronic Supplementary Material 3: Tables of statistics for study design comparisons
Table S3.1 Weighted linear regressions between latitude, study duration (days), experiment area (m2), and Hedges’ d for all
taxonomic groups
Latitude
Study duration
Study size
Taxonomic
group
Terrestrial
Plant
Invertebrate
Slope
direction
+
+
Vertebrate
Marine
Plant
Invertebrate
Vertebrate
Freshwater
Plant
Invertebrate
Vertebrate
-
n
P
130
136
Slope
direction
n
P
Slope
direction
n
P
130
136
0.0938
0.2356
108
79
0.2350
0.8352
17
0.0152
0.0155
0.4848
17
0.9839
17
0.3224
95
58
19
0.9291
0.1044
0.2741
93
56
19
0.4466
0.4109
0.4130
89
58
19
0.6149
0.2748
0.1279
56
0.4623
54
55
0.7268
98
6
0.0038
0.7413
0.0195
0.7635
0.2911
98
6
0.6655
0.1450
+
98
6
Notes: The natural log of study duration and experiment areas was used to normalize the residuals. The direction of the slope is given
for significant regressions only
Table S3.2 Mean effect sizes, confidence limits, and statistics for comparisons of enemy effects among different exclosures methods
Taxonomic
Exclosure
Hedges’ Lower
Upper
n
QB
d.f. P
group
method
d
95% CL
95% CL
Terrestrial
Plant
Exclosurea
0.51
0.19
0.82
53
Insecticide
0.32
-0.10
0.72
31
b
Sterilization
0.33
0.11
0.58
46
0.96
2
0.6191
Invertebrate
Vertebrate
Freshwater
Plant
Exclosurea
Manualc
Barrierd
Exclosurea
Manuale
0.87
0.42
0.60
0.81
0.54
0.68
-0.11
0.40
0.05
0.04
1.07
0.88
0.85
1.52
1.06
75
17
44
10
7
Exclosurea
1.42
1.00
1.88
31
0.86
0.58
0.89
0.57
0.32
0.46
1.17
0.87
1.36
25
66
32
f
Invertebrate
Barrier
Exclosurea
Barrierf
5.37
2
0.0682
0.23
1
0.6309
3.92
1
0.0477
1.56
1
0.2110
Note. Statistical comparisons were conducted among different exclosure methods within taxonomic goups. Confidence limits are 95 %
bias-corrected confidence intervals. Sample sizes are given (i.e., number of observations). Significance of QB was estimated using chisquare distributions. Significant comparisons given in boldtype.
a
Exclosures consisted of cages or mesh
b
Sterilization represents sterilizing soil to remove microbial and fungal pathogens
c
Manual removal for terrestrial insects consisted of removing by hand or vacuum
d
Barriers for terrestrial insects consisted of using tanglefoot on trees to exclude ants
e
Manual removal for terrestrial vertebrates consisted of trapping
f
Barriers in freshwater ecosystems consisted of electric barriers
Table S3.3 Mean effect sizes, confidence limits, and statistics for comparison of enemy effects between different response variable
types.
Taxonomic
Response types
Hedges’ Lower
Upper
n
QB
d.f. P
group
d
95% CL
95% CL
Terrestrial
Plant
Abundancea
0.39
0.18
0.60
67
b
Biomass
0.40
0.09
0.72
63
>0.01 1
0.9876
Marine
Plant
Invertebrate
Freshwater
Plant
Invertebrate
Abundancea
Biomassb
Abundancea
Biomassb
0.85
0.92
0.46
1.57
0.30
0.49
-0.01
0.88
1.40
1.35
0.97
2.27
18
77
32
26
Abundancea
Biomassb
1.86
1.02
1.41
0.76
2.32
1.32
Abundancea
Biomassb
0.51
0.83
0.23
0.47
0.83
1.17
0.03
1
0.8562
7.23
1
0.0071
9
47
4.53
1
0.0334
45
53
1.94
1
0.1631
Note. Statistical comparisons were conducted between different response variable types within taxonomic groups. Confidence limits
are 95 % bias-corrected confidence intervals. Sample sizes are given (i.e., number of observations). Significance of QB was estimated
using chi-square distributions. Response variables of terrestrial invertebrates and vertebrates, marine vertebrates, and freshwater
vertebrates all only reflected measures of abundance.
a
Abundance was measured as: abundance, density, number of new recruits, and/or survivorship
b
Biomass was measured as: total biomass, percent cover, chlorophyll a, ash free dry mass
Table S3.4 Mean effect sizes, confidence limits, and statistics for comparisons of enemy effects among different levels of taxonomic
resolution.
Taxonomic
Taxonomic
Hedges’ Lower
Upper
n
QB
d.f. P
group
resolution
d
95% CL
95% CL
Terrestrial
Plant
Species
0.41
0.22
0.61
115
Community
0.28
-0.14
0.78
15
0.18
1
0.6651
Invertebrate
Species
0.96
0.73
1.22
59
Marine
Plant
Invertebrate
Vertebrate
Freshwater
Plant
Invertebrate
Community
0.57
0.41
0.75
77
Species
Community
Species
Community
Species
1.23
0.73
0.87
1.34
1.13
0.68
0.25
0.41
0.19
0.73
1.76
1.21
1.33
2.81
1.69
33
62
48
10
10
Community
0.54
0.27
0.82
9
Species
Community
Species
Community
0.98
1.46
0.48
0.73
0.67
1.07
0.10
0.46
1.33
1.93
0.96
1.02
34
22
21
77
7.05
1
0.0079
1.93
1
0.1643
1.80
1
0.4225
2.92
1
0.0874
2.54
1
0.1108
Note. Statistical comparisons were conducted among different levels of taxonomic resolution within taxonomic groups. Confidence
limits are 95 % bias-corrected confidence intervals. Sample sizes are given (i.e., number of observations). Significance of QB was
estimated using chi-square distributions. Significant comparisons given in boldtype. Community was measured as species in the same
taxonomic group (e.g., beetles, chironomds), functional group (e.g., sap-suckers, macroalgae), life history form (e.g., perennials
plants).