California State University, Northridge the Use of Terrestrial

California State University, Northridge

The Use of Terrestrial Arthropods to Evaluate Coastal Sage Scrub Restoration

Projects in the Santa Monica Mountains National Recreation Area

A thesis submitted in partial fulfillment of the requirements

For the degree of Master of Science in Biology

Wendy Dunbarr

May, 2016

The thesis of Wendy Dunbarr is approved:

______

Dr. Tim Karels Date

______

Dr. James. N. Hogue Date

______

Dr. Irina Irvine Date

______

Dr. Paula Schiffman, Chair Date

California State University, Northridge

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Acknowledgements

I want to extend tremendous thanks to Dr. James N. Hogue for the countless hours of support you provided in arthropod identification, brainstorming, canonical correspondence analysis interpretation, and moral support. You are a true mentor and a real mensch.

Dedications

To my husband, Jon, for all of your support and patience. You were a wonderful field assistant, and a much-appreciated bug picker. You talked me down when I was on high anxiety, and you talked me up when I was at my low points. Your encouragement and sound-boarding made all the difference. Thank you for all you did to make this degree happen.

To the Wendy of 2009 ˗ you really did this. As Richard Bach wrote, “What the caterpillar calls the end, the Master calls a butterfly.” Even though it looked like the end, you pressed on and things have turned out beautifully. You figured out what you wanted and took all the leaps of faith and baby steps that were required to get here.

Congratulations.

Table of Contents

Signature Page iii

Acknowledgement iv

Dedication v

List of Tables vii

List of Figures viii

Abstract ix

Section 1: Introduction 1

Section 2: Methods 7

Study Sites 7

Vegetation Sampling 9

Arthropod Sampling and Identification 10

Data Analysis 11

Section 3: Results 14

Vegetation 14

Arthropods 15

Section 4: Discussion 19

Vegetation 19

Arthropods 21

Conclusions 26

Literature Cited 46

Appendix A: Terrestrial arthropod list 54

List of Tables

Table 1. Vegetation cover data for each plot in three types of sites 33 at Cheeseboro Canyon.

Table 2. Vegetation cover data for each plot in three types of sites 34 at Zuma Canyon.

Table 3. Canonical coefficients for the five environmental variables 36 for both canyons.

Table 4. Arthropod taxa with the 10 highest loadings for both canonical 38 correspondence analysis axes from Cheeseboro Canyon and the environmental variables they were associated with Table 5. Arthropod taxa with the 10 highest loadings for both canonical 40 correspondence analysis axes from Zuma Canyon and the environmental variables they were associated with

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List of Figures

Figure 1. Location of sample locations within the Santa Monica 29 Mountains National Recreation Area

Figure 2. Mean plant species richness across all plots for the three 30 site types in Cheeseboro Canyon.

Figure 3. Mean plant species richness across all plots for the three 30 site types in Zuma Canyon.

Figure 4. Percentages of mean vegetation cover, mean native species 31 cover, and mean Salvia leucophylla cover at three site types in Cheeseboro Canyon.

Figure 5. Percentages of mean vegetation cover, mean native species 32 cover, and mean Salvia mellifera cover at three site types in Zuma Canyon.

Figure 6. Species accumulation curve for Cheeseboro Canyon. 35

Figure 7. Species accumulation curve for Zuma Canyon. 35

Figure 8. Canonical correspondence analysis ordination diagram for 37 Cheeseboro Canyon.

Figure 9. Canonical correspondence analysis ordination diagram for 39 Zuma Canyon.

Figure 10. Mean terrestrial arthropod richness and abundance per plot 41 at three site types from Cheeseboro Canyon.

Figure 11. Mean terrestrial arthropod richness and abundance per plot 42 at three site types from Zuma Canyon.

Figure 12. Shannon index and Pielou’s evenness values for terrestrial 43 arthropods at three site types from Cheeseboro Canyon.

Figure 13. Shannon index and Pielou’s evenness values for terrestrial 44 arthropods at three site types from Zuma Canyon.

Figure14. Mean percentages of non-native terrestrial arthropod taxa 45 at Cheeseboro Canyon.

Figure 15. Mean percentages of non-native terrestrial arthropod taxa 45 at Zuma Canyon.

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Abstract

The Use of Terrestrial Arthropods to Evaluate Coastal Sage Scrub Restoration

Projects in the Santa Monica Mountains National Recreation Area

Wendy Dunbarr

Master of Science in Biology

Non-native invasive plants threaten native plants in ecosystems through competition for resources, alteration to ecosystem functions and disturbance regimes, and changes to food webs and mutualistic relationships. Decades of intense disturbance and fragmentation of coastal sage scrub in Southern California have led to type conversion from mixed native shrub cover to non-native annual grassland in many places.

Restoration efforts have been carried out by various government and private land managers in an effort to preserve existing coastal sage scrub and create additional habitat.

Ecological restoration typically focuses on vegetation for both restoration activities and assessments of project outcomes. Additional measures of ecosystem function should be considered when evaluating the progress of restoration projects. Terrestrial arthropods occupy a wide breadth of niches and provide valuable ecosystem services (seed dispersal,

ix decomposition, food sources for higher trophic levels). They are also sensitive to subtle, small-scale changes in the environment, which makes them more likely to be restored before larger animals. This study compared terrestrial arthropod assemblages along with vegetation characteristics among three types of sites (invaded, restored, native) to evaluate the success of two coastal sage scrub restoration projects within the Santa

Monica Mountains National Recreation Area. Terrestrial arthropod assemblage compositions were successfully restored at both canyons. These results agreed with vegetation results at Cheeseboro Canyon, but contradicted vegetation results at Zuma

Canyon. The results of this study indicate that restoration projects at both canyons were successful. The successful restoration of arthropod assemblage compositions despite spatial isolation and vegetative differences of the restored areas supported the Field of

Dreams hypothesis that “if you build it, they will come”. The addition of terrestrial arthropod data to the standard practice of vegetation monitoring provided a more thorough evaluation of the status of these restoration projects, and should be used by land managers in the future.

Section 1: Introduction

Invasive non-native plants threaten native plants and animals in ecosystems through competition for resources, alterations to ecosystem functions, changes to food webs and mutualistic relationships (Vitousek et al. 1997, Wilcove et al. 1998, Kourtev et al. 2002, Gurevitch and Padilla 2004, Pringle et al. 2009, Vil et al. 2011), and increases in frequency and intensity of disturbances (O’Leary 1989, Mack and D’Antonio 1998,

Bossard and Randall 2007). Additionally, they can change native plant community assemblages, structure, and function (Jackson 1985, Rosenzweig 2001, Gurevitch and

Padilla 2004, Stinson et al. 2006), and in some cases displace the native plant community entirely (Davis 2003, Brown and Gurevitch 2004, Gooden and French 2014).

Twenty percent of California’s flora consists of non-native species (Randall et al.

1998), the majority of which originated in regions with Mediterranean-type climates

(Randall et al. 1998, Bossard and Randall 2007). Among these species, annual grasses and forbs are the most likely to cause drastic changes in the communities they occupy

(Gurevitch and Padilla 2004). Introduced around the time of European settlement, they dominate California grasslands (Jackson 1985, Stromberg et al. 2001) and are abundant in coastal sage scrub stands (Minnich and Dezzani 1998, Rundel 2007). Decades of intense disturbance and fragmentation of coastal sage scrub in Southern California have led to type conversion from mixed native shrub cover to non-native annual grassland

(Rundel 2007) in many places.

California coastal sage scrub is a plant community dominated by shrubs and subshrubs, including Salvia species, Artemisia californica, and Baccharis pilularis

(Rundel 2007, Fleming et al. 2009). Many coastal sage scrub plants are drought

1 deciduous, losing all or most of their leaves in the dry, hot summer months, and growing new leaves when the rainy season begins, usually in late fall (Rundel 2007). This community occurs at elevations below 300 m along the coast and in the semi-arid interior of California, ranging from the San Francisco Bay area to El Rosario in Baja California

(Westman 1981b, Rubinoff 2001, Rundel 2007).

Küchler (1977) estimated that coastal sage scrub once covered 2.5% of the area of

California. It currently occupies just 10-15% of its historic range (Westman 1981b).

Recent evaluations of a coastal sage scrub survey performed in the 1930’s found only

40% of the original survey area still remaining relatively intact (Minnich and Dezzani

1998, Talluto and Suding 2008). This reduction in range is the result of urban and agricultural development, increased fire frequency, and invasion by non-native grasses and forbs (Minnich and Dezzani 1998, Talluto and Suding 2008, Engelberg 2011).

Despite these impacts, the coastal sage scrub ecosystem includes about 100 rare and endangered plants and animals (Bowler 2000, Fleming et al. 2009).

The California Department of Fish and Wildlife developed a Natural

Communities Conservation Plan for coastal sage scrub in 1992 because the threats to coastal sage scrub are expected to continue, and because several federally listed species occur in this habitat. Since that time, coastal sage scrub restoration efforts have been carried out by various government and private land managers (U. S. Fish and Wildlife

Service 2015). The goals of ecological restoration vary depending upon specific environmental circumstances (Hobbs 2007), but they generally include reversing environmental damage and native population declines, and restoring ecosystem functions

(Foin et al. 1998, Grimbacher and Catterall 2007, Hobbs 2007).

Restoration efforts typically focus on reducing non-native plant cover and enhancing native vegetation (Bowler 2000, Irvine et al. 2013). The first step is removal of invasive plant species, through mechanical or chemical means. This is followed by the establishment of native vegetation cover (McCoy and Mushinsky 2002, Suding 2011,

Irvine et al. 2013). Ecological restoration efforts generally conclude when the native plants are able to persist without supplemental care (i.e., watering, weed removal, exclusion of herbivores) (McCoy and Mushinsky 2002, Fragoso and Varanda 2011,

Suding 2011). This approach relies on the important assumption, known as the Field of

Dreams hypothesis, that “if you build it, they will come” (Palmer et al. 1997). According to this hypothesis, once the foundational elements of the ecosystem (plants in terrestrial systems) have been restored, natural processes will take over and facilitate the return of the native fauna and other ecosystem processes without additional active manipulation

(Foin et al. 1998, Longcore 2003, Suding 2011).

Setting specific goals with measurable outcomes is essential in the evaluation of restoration projects (Hobbs 2007, Zedler 2007). McCoy and Mushinsky (2002) developed a four step plan for evaluating restoration success: 1) develop a restoration goal, 2) find a suitable reference site based on the goal (often nearby intact habitat), 3) determine the difference between the restoration goal and the reference site, and 4) decide if the difference is acceptable. Under this framework, an acceptably small difference between the structure and function of the restored system and that of the reference system is indicative of success (McCoy and Mushinsky 2002).

The success of terrestrial ecosystem restoration projects is most commonly based on vegetation data (McCoy and Mushinksy 2002, Fragoso and Varanda 2011). However,

3 several studies have shown that even when vegetation structure and biodiversity measures indicate the success of a restoration project, the fauna and ecosystem processes do not automatically return to the restored area (Zedler 1993, Henry and Schultz 2013).

Other studies have found that restored areas support fauna compositions that differ from intact native habitat (Klein et al. 2007, Gardner et al. 2009, Freeman et al. 2015). Such outcomes highlight the need to address not just vegetation characteristics, but also interspecific interactions and the importance of the system’s functional aspects (e.g., nutrient cycling, food webs, etc.) when planning and executing ecological restoration projects (Fragoso and Varanda 2011).

Since the mid-1970s there has been a steady increase in published studies that look beyond the vegetation and explore additional indicators of restoration success

(Majer 2009). These studies have focused on factors such as physical properties of soils

(Barbour et al. 1999, Dickens et al. 2013), soil microbes (Bozzolo and Lipson 2013,

Irvine et al. 2013), nutrient cycling (Yelenik and Levine 2010, Yelenik and Levine 2011), vertebrates (Chase et al. 2000, Rubinoff 2001), and terrestrial arthropods (Kremen et al.

1993, Longcore 2003, Burger et al. 2003, Nemec and Bragg 2008).

Among terrestrial animals, arthropods occupy the greatest breadth of niches

(Kremen et al. 1993, Longcore 2003). Terrestrial arthropods provide many ecosystem services, which include pollination, seed dispersal, and decomposition, as well as serving as food for other animals. This diversity of functions makes them indicators of the nutrient cycling and interspecific interactions taking place in ecosystems (Longcore 2003,

Burger et al. 2003). In addition, the small size of terrestrial arthropods and their tremendous diversity of life histories mean that they are sensitive to subtle, yet important

4 small-scale changes in the environment (Mortimer et al. 1998, Burger et al. 2003,

Longcore 2003, Nemec and Bragg 2008). Therefore, arthropod assemblages may be successfully restored to a habitat before other, larger taxa have reestablished (Nemec and

Bragg 2008). Their short generation times also allow for tracking of year-to-year changes in species composition and abundance (Longcore 2003) that reflect the progress of ecological restoration projects over time.

Many studies have compared arthropod assemblages between two site types: native vs. invaded or native vs. restored (here “native” refers to natural communities that are intact or relatively undisturbed) to evaluate the success of restoration projects (Majer et al. 1984, Nemec and Bragg 2008, Heleno et al. 2008, Heleno et al. 2010). However, in order to fully evaluate whether ecosystem restoration efforts have been successful, three types of sites (native, invaded, and restored) should be compared (Longcore 2003,

Gratton and Denno 2005, Gardner et al. 2009). This three-way comparison can elucidate whether arthropod assemblages in restored ecosystems more closely resemble those of invaded ecosystems or those of native ecosystems. For example, Gratton and Denno

(2005) found that native and restored habitats had vegetation characteristics and arthropod assemblages that were similar to one another. They also found that the terrestrial arthropods in the invaded habitat had lower richness and abundance and, hence, lower diversity. In addition, Gardner et al. (2009) found that although vegetation characteristics and arthropod assemblage compositions were distinct for all three areas, the arthropod assemblage composition in restored areas was more similar to native reference sites than to invaded reference sites.

In keeping with McCoy and Mushinsky (2002), a successfully restored ecosystem will support an arthropod assemblage that is more similar to reference native sites than to reference invaded sites. To assess the success of coastal sage scrub restoration projects, my study compared vegetation composition and terrestrial arthropod assemblages among invaded, restored, and native sites at two coastal sage scrub locations in southern

California’s Santa Monica Mountains National Recreation Area. I expected that restored sites at both locations would support terrestrial arthropod assemblages (i.e., taxa richness, abundance of individuals, and composition of taxa) that were more similar to reference native sites than to those of reference invaded sites because of the similarity of vegetation characteristics of the two areas. The presence of appropriate host plants (Nelson and

Wydowski 2008, Nemec and Bragg 2008, Heleno et al. 2010) and the complexity of habitat structure (Jansen 1997, Gratton and Denno 2005, Grimbacher et al. 2007, Wodika et al. 2014, Noreika et al. 2015) influence the presence and distribution of terrestrial arthropods. Because the vegetation type and habitat structure of the invaded areas is very different from the native and restored sites, I expected that arthropod assemblages in invaded areas would be different from those in the other two types of sites.

Section 2: Methods

Study Sites

Data were collected at two locations in the Santa Monica Mountains National

Recreation Area (Figure 1) that represented the range of coastal sage scrub environments in southern California: Cheeseboro Canyon (3 9’ N, -118 3’ E, 1025 m elevation) and

Zuma Canyon (3 1’ N, -118 8’ E, 200 m elevation). Both canyons had disturbance histories that were typical of Los Angeles and Ventura Counties (Minnich and Dezzani

1998, Rundel 2007, Talluto and Suding 2008, Engelberg 2011). These disturbances included livestock grazing and cultivation between about 1800 and 1980, invasions by

Mediterranean region annual grasses and forbs, and periodic wildfires. Both sites had large areas of intact coastal sage scrub, along with large amounts of vegetation dominated by invasive non-native species (particularly annual grasses including Avena and Bromus species and mustards including Brassica nigra and Hirschfeldia incana), and areas that have undergone ecological restoration. The invaded areas at both canyons were inside of or near to fuel modification zones that were mowed annually to suppress wildfire.

National Park Service data from 1956 to 2013 show that wildfires typically occur at 8.7 year intervals at Zuma Canyon and 9.5 year intervals at Cheeseboro Canyon (Robert

Taylor, personal communication).

Cheeseboro Canyon was the hotter and more xeric of the two locations, situated inland in the Simi Hills. The restored sites there were initially established by the

National Park Service in February 2004 as part of an unrelated study. At that time, the invasive non-native species were removed using brush cutters. Subsequently, Salvia leucophylla and Artemisia californica, shrub species that dominate intact coastal sage

7 scrub in the canyon, were planted along with the native bunchgrass Stipa lepida. All native plants were grown in conetainers from seed in a nursery and transplanted to the restored areas. Plants were 40 centimeters from their nearest neighbor in all directions.

There were no surviving S. lepida individuals in any of the restored areas by August 2005

(Marti Witter, personal communication).

Five restored sites from the original study were in suitable condition (with relatively little invasive non-native plant cover and numerous surviving S. leucophylla and A. californica plants) for inclusion in this study. These restored sites ranged from approximately 117 m2 to 204 m2. Research plots of uniform size (8 × 10 m) were established within each of the restored sites in April 2012. This plot size allowed for buffers of at least 1.5 m from each plot edge to avoid sampling of arthropods that may occur in the ecotone between the restored and invaded areas (Ward et al. 2001).

Analogous plots (same sizes, similar slopes and aspects) were established in invaded

(dominated by non-native invasive species) and intact native (dominated by coastal sage scrub) sites within the canyon in the same time period. Due to the spatial distribution of the three site types in the landscape, the native sample plots were separated from the invaded and restored sample plots by approximately 2.5 km. In 2013, to address this issue and better represent the natural vegetation in the canyon, three additional native plots were established in the nearest intact native coastal sage scrub, approximately 1.95 km from the invaded and restored plot locations, in March 2013. As a result, there were five sample plots each for invaded and restored sites, and eight sample plots for native sites.

Zuma Canyon is located approximately 2.1 km from the Pacific Ocean in the

Santa Monica Mountains. This relatively close proximity to the ocean means that the coastal sage scrub there experiences more consistently cool and mesic conditions than at

Cheeseboro Canyon. The restored areas in Zuma Canyon occurred in close proximity to both invaded and intact native areas. This allowed for 8 × 10 m plots to be set up in 5 blocks, each consisting of an invaded site, a restored site, and an intact native site using the same methods as in Cheeseboro Canyon. Three blocks were established near the canyon mouth. The restoration areas in these three blocks were initiated by the National

Park Service in January of 2008, at which time invasive grasses were removed using brush cutters. Native plants common in this part of the Santa Monica Mountains (e.g.,

Salvia mellifera, Salvia leucophylla, Baccharis pilularis, Artemisia californica) were grown from seeds in a nursery and planted from one gallon containers. The other 2 blocks were established approximately 275 m away. Restoration efforts for these blocks began in the spring of 2009 when National Park Service staff removed trees from a decommissioned avocado grove. Subsequently, the same palette of native species was planted from one gallon containers. Plants in both areas were planted in groups of three, with 75 centimeters in all directions between each cluster and the next nearest cluster

(Irina Irvine, personal communication). All research plots in Zuma Canyon were established in March 2013.

Vegetation Sampling

Vegetation data were collected from each plot using a modified point-intercept method in July 2013. Within each plot, vegetation intersecting with points at 0.5 m

9 intervals along 10 parallel (1 m apart) 8 m transects were sampled (135 sample points per plot). When more than one plant species occurred at a given sample point, the plant providing more canopy cover was identified and recorded. This occurred at an estimated rate of five points per plot. The presence of more than one species at a given point was most common in restored and native plots. At these points, the branches of two shrubs overlapped one another. These data were used to calculate species richness, percent total vegetation cover, percent native vegetation cover, and dominant species cover for each plot. Dead woody material that intersected sample points was also recorded and included in the calculation of total vegetation cover. As a result of drought conditions, there were few to no live plants in the invaded areas at Cheeseboro Canyon. Species were identified from plant remains and these results were compared to vegetation survey data from April

2012 for the same plot.

Arthropod Sampling and Identification

Terrestrial arthropod assemblages were sampled at all 3 site types (invaded, restored, and native) in both canyons during their periods of peak adult activity. Pitfall traps consisting of 2 nested cylindrical plastic containers measuring 12 cm in diameter, and 18 cm in depth were inserted in the ground with the opening flush with the soil surface. The traps were dosed with 295 mL of a 50:50 mixture of propylene glycol based antifreeze and water as per Parr and Chown (2001), Ward et al. (2001), Longcore (2003), and Thomas (2008). Propylene glycol was used because it is non-toxic to vertebrates, is a stable preservative, and does not attract insects (Thomas 2008). Four traps were placed in each plot using the following array: two traps in the interior of the plot and two traps at

10 the outer edge of the plot; one up slope and one down slope. Each trap was at least 1 m from its nearest trap, as this inter-trap spacing has similar catch rates as greater inter-trap spacing (Ward et al. 2001). All traps were kept in place for three weeks prior to collections on May 24 and 31, 2013 at Cheeseboro Canyon, and June 6 and 12, 2013 at

Zuma Canyon.

The use of pitfall traps allowed for the continuous day and night sampling of resident terrestrial arthropods in each plot. Despite using pitfall traps in an effort to sample primarily ground dwelling arthropods, surface-active volant arthropods were also trapped and were included in the analyses. All terrestrial arthropods captured were identified to taxonomic order and enumerated. In cases where identification to species or family was not possible, unique morphospecies identities were assigned.

Data Analysis

Data for all variables were examined for homogeneity of variance and normality and were transformed to meet assumptions when necessary. Vegetation and terrestrial arthropod data for each canyon were analyzed separately because there was no replication of study location.

Vegetation data were analyzed using a nested analysis of variance (SPSS version

22, IBM Corp. 2013). The dominant native species was defined as the species that made up the largest percentage of native cover among all plots. This was S. leucophylla at

Cheeseboro Canyon and S. mellifera at Zuma Canyon. Dominant non-native plant species were defined the same way, and were Bromus madritensis in Cheeseboro Canyon and Avena barabata in Zuma Canyon. Because the dominant native species did not

11 occur in any of the invaded plots, the percentage of dominant native cover was compared only between the restored and native site types.

Each plot was treated as an experimental unit. Therefore the terrestrial arthropod data were summed across traps to create mean values for each sample plot. Terrestrial arthropod richness and abundance of individuals, as well as the Shannon diversity index,

Pielou’s evenness index, percent non-native taxa, and percent rare taxa were compared among the three site types using factorial nested analysis of variance (SPSS version 22,

IBM Corp. 2013). Non-native taxa were defined as arthropod species that had been identified to species level and whose introduction to California has been documented.

Rare taxa were defined as those that occurred in less than 5% of all pitfall samples

(Gauch 1982) at each canyon.

Canonical correspondence analysis (PC-ORD version 5, McCune and Mefford

2005) was used to explore relationships between environmental variables and arthropod abundance. The five environmental variables used were percent total vegetation cover, percent native species cover, plant species richness, percent dominant native species cover, and percent dominant non-native species cover. Canonical correspondence analysis is one of the most widely used gradient analysis techniques in ecological studies

(Palmer 1993, Peck 2010) to explore relationships between species assemblages and their environment (ter Braak and Verdonschot 1995). In this analysis, ordination axes based on species abundance data are constrained into linear combinations of the environmental variables (ter Braak 1987). Canonical correspondence analysis is robust to skewed species distributions and sparse data sets (Palmer 1993, ter Braak 1986, Peck 2010),

12 which are common characteristics of species abundance data, as well as intercorrelated environmental variables (Palmer 1993).

Canonical correspondence analysis uses reciprocal averaging, which places rare species on the extreme ends of ordination axis 1, and can result in distortion of the subsequent axes. As a result, it is common practice to remove species occurring in less than 5% of the samples from the data set prior to running the analysis (Gauch 1982).

Species that occurred in less than 5% of the samples from all site types combined for each canyon were removed. Rare arthropods accounted for 104 taxa sampled from

Cheeseboro Canyon and constituted 39% of the total richness. The Zuma Canyon plots supported 134 rare taxa, accounting for 32% of the total richness. The proportion of rare taxa did not differ significantly among the three site types at either canyon. Removal of rare species resulted in the use of 269 taxa for Cheeseboro Canyon and 283 taxa for

Zuma Canyon in ordination based analyses.

Section 3: Results

Vegetation

The two canyons had different patterns of plant species richness among the three types of sites. At Cheeseboro Canyon the mean plant species richnesses of the restored and native site types were similar (2.4/plot and 2.5/plot, respectively) and were greater than the species richness of the invaded sites (1.6/plot; F2, 15 = 3.17, p = 0.07; Figure 2).

At Zuma Canyon, the mean plant species richness was significantly higher (F2, 12 = 11.82, p = 0.001) in the restored sites (7.4/plot) than at the other two site types (invaded:

3.8/plot, native: 3.6/plot; Figure 3). The restored sites had the least amount of total vegetation cover at both Cheeseboro and Zuma canyons. The percentages of total cover differed significantly among the 3 types of sites at Cheeseboro Canyon (F2, 15 = 13.40, p<0.001; Figure 4A). The restored sites had 19.60% and 14.13% less cover than the invaded and native site types, respectively. Like Cheeseboro Canyon, the restored site types at Zuma Canyon had 11.4% and 6% less vegetation cover than the invaded and native sites, respectively (F2, 12 = 8.51, p < 0.01; Figure 5A).

The restored and native sites at Cheeseboro Canyon did not differ in either percent native vegetation cover (Figure 4B) or percent S. leucophylla cover (Figure 4C).

The three native plots established in Cheeseboro Canyon in 2013 had different species compositions than the five native plots established in 2012. These plots were dominated by A. californica rather than S. leucophylla and were the only ones to include Hazardia squarrosa (Table 1). At Zuma Canyon there was also no significant difference in percent native vegetation cover between the restored and native site types (Figure 5B). However, the restored and native site types did differ significantly in percent cover for S. mellifera

(F2, 12 = 10.56, p < 0.05; Figure 5C); with an average of 45% more S. mellifera in the native sites (Table 2). Although S. mellifera was the dominant native species across all plots at Zuma Canyon, B. pilularis was the dominant species in the restored plots.

Additionally, Artemisia douglasiana, Malacothamnus fasciculatus, and Isocoma menziesii were present only in the restored plots.

Arthropods

The 72 pitfall trap collections from Cheeseboro Canyon averaged 600.5 ± 78.9

(SE) individuals of 48.6 ± 2.3 (SE) taxa per trap and represented 27 arthropod orders.

Similarly, Zuma Canyon’s 60 pitfall traps averaged 677.9 ± 59.7 (SE) individuals of 55 ±

1.9 (SE) taxa per trap and represented 25 arthropod orders. Taxa accumulation curves

(SPSS version 22, IBM Corp. 2013) were plotted for both Cheeseboro Canyon (Figure 6) and Zuma Canyon (Figure 7). Species accumulation curves (“taxa accumulation curves” here) plot the accumulated number of sampled taxa against the sampling effort. Initially, the curve rises steeply as many new taxa are recorded from the initial samples. Then, the curve rises less steeply and levels out as fewer new taxa are recorded as more samples are collected (Gotelli and Colwell 2001, Ugland et al. 2003). The curves for both graphs approached an asymptote, which indicated that this level of sampling intensity was adequate to compare arthropod richness across site types (Gotelli and Colwell 2001,

Ugland et al. 2003, Grimbacher and Catterrall 2007).

Canonical correspondence analysis for Cheeseboro Canyon produced 3 axes which collectively explained 42% of the total variance (Table 3). Because axis 3 explained so little of the variance (6.8%) it was excluded from further analyses. Axis 1

15 was primarily related to the covers of the non-native invasive annual grass B. madritensis, native vegetation, and the dominant native shrub S. leucophylla. Axis 2 was related to the covers of B. madritensis and native vegetation (Table 3). Five of the eight native plots had similar arthropod assemblages and formed a cluster in the lower left quadrant of Figure 8. Similarly, four of the five restored plots clustered together on the left side of the graph. The environmental variable associated with these plots was S. leucophylla cover. The three native plots that were established in the nearest intact vegetation without regard to slope or aspect clustered with one of the restored plots in the lower right quadrant of the graph because of their association with high plant species richness. The five invaded plots clustered loosely together in the upper right quadrant of

Figure 8 and had high covers of the non-native annual grass B. madritensis and total vegetation.

A variety of taxonomic and feeding groups were represented in the ten highest arthropod loadings from the Cheeseboro Canyon canonical correspondence analysis.

One taxon, Encyrtidae7, had loadings in the top 10 for both axes (Table 4). Nine other taxa were positively associated with high native S. leucophylla cover. This group consisted of three herbivores, two predators, three parasitoids, and one omnivore. High non-native B. madritensis cover was correlated with three detritivores, one herbivore, three predators, and one nectivore. Two taxa, one parasitoid and one carnivore, were positively correlated with plant species richness.

Canonical correspondence analysis for Zuma Canyon also resulted in 3 axes, and these axes explained a similar amount of the total variance (48.8%, Table 3). Axis 3 contributed only 8.5% to the variance and was excluded from further analyses. Axis 1

16 was related to native vegetation cover whereas Axis 2 was primarily related to the covers of total vegetation and the non-native invasive grass A. barbata (Table 3). The restored and native plots had similar terrestrial arthropod assemblages and clustered tightly together in the upper left quadrant of Figure 9. These plots were associated with high covers of native vegetation and the dominant native shrub S. mellifera, as well as high plant species richness. The invaded plots were distributed along axis 2 on the right side of Figure 9. Three invaded plots had similar arthropod assemblages and were associated with high total vegetation cover. The other two invaded plots had distinctly different arthropod assemblage compositions. These two plots were associated with high cover of the non-native annual grass A. barbata.

The taxa with the ten highest canonical correspondence analysis loadings for

Zuma Canyon also spanned numerous taxonomic groups and feeding guilds (Table 5).

Two herbivores and three parasitoids were associated with high total vegetation cover.

The remaining 14 taxa were positively correlated to high A. barbata cover. This group was comprised of five herbivores, one fungivore, five predators, and three parasitoids.

At Cheeseboro Canyon there were no significant differences among the three types of sites for total arthropod richness (Figure 10A) or total arthropod abundance

(Figure 10B). While richness was not significantly different among the three site types at

Zuma Canyon (Figure 11A), there was a significant difference for arthropod abundance

(F2, 12 = 6.97, p = 0.01; Figure 11B). Arthropod abundance at the native sites was, on average, 56.2% and 47.6% lower than at the invaded and restored sites, respectively.

The three site types at Cheeseboro Canyon did not differ in Shannon diversity

(Figure 12A) or Pielou’s evenness (Figure 12B) values. In contrast, Shannon index

17 values for Zuma Canyon indicated a trend toward higher diversity at native sites than in the other two kinds of sites (F2, 12 = 3.38, p = 0.07; Figure 13A). Pielou’s evenness was also significantly higher (F2, 12 = 4.10, p = 0.04) in the native sites than in the invaded and restored sites (Figure 13B) at Zuma Canyon.

Of the 48 species identified at Cheeseboro Canyon, seven were not native to

California. These non-native species accounted for 1.9% of the total richness. There was no difference in the percentages of non-native taxa among the three site types (Figure 14) at Cheeseboro Canyon. Fifty-eight species were identified at Zuma Canyon and 13 of them were non-natives. They accounted for 3.1% of the total richness at Zuma Canyon.

There were significantly more non-native taxa (F2, 12 = 4.72, p = 0.03) in the invaded site type than in the restored and native site types at Zuma Canyon (Figure 15).

Section 4: Discussion

Vegetation

The similarities in plant species richness, native species cover, and S. leucophylla cover between the restored and native plots at Cheeseboro Canyon indicated that coastal sage scrub vegetation was successfully restored (McCoy and Mushinksy 2002, Fragoso and Varanda 2011). The plants installed in the restored areas were of the same species composition as nearby intact coastal sage scrub, which allowed for the similarity of plant species richness between the restored and native sites. The density of plantings, persistence of installed plants, and/or minimal reinvasion by non-native annuals likely contributed to the similarity in percent cover of native species and S. leucophylla.

Another factor that may have contributed to the percentage of cover of native species in the restored areas was the amount of time since the installation of the plants in the restored areas (9 years). Other studies have shown that as restored sites mature, the plant community becomes more similar to native reference sites in terms of plant size and structural complexity (Westman 1981b, Majer et al. 1984, Longcore 2003, Grimbacher and Catterall 2007).

In contrast, at Zuma Canyon, native plant species cover was the only measure for which the restored plots were more similar to the native plots than to the invaded plots.

Otherwise, the vegetation in the restored plots was distinctly different from that of both the invaded and restored plots. These differences indicated that the restoration project did not successfully recreate the vegetation characteristics found in intact coastal sage scrub. The low total vegetation cover in the restored plots resulted from low survivorship of the installed plants (Marti Witter, personal communication). The mortality rate for the

19 plants transplanted into restored areas at Zuma Canyon was forty percent. Moreover, the significant differences in plant species richness and S. mellifera cover between the restored and native plots at Zuma Canyon were artifacts of the adaptive management of the restoration efforts there. As a result of low plant survivorship, National Park Service re-planted the areas with a variety of native shrub species in an effort to successfully establish native vegetation. While all of the plant species used in the Zuma Canyon restoration were natural constituents of coastal sage scrub in southern California, they were more abundant in restored areas than in nearby intact habitat in the canyon (personal observation). This resulted in restored areas with more species than the other two types of sites and different species composition and lower S. mellifera cover than the native sites.

Among the three site types, cover of total vegetation was lowest in restored areas, due, at least in part, to S. lepida die off in Cheeseboro Canyon and the low survivorship of installed plants in Zuma Canyon (Irina Irvine, personal communication). This mortality in the restored sites resulted in more bare ground than was found in the other two types of sites. In comparison, the invaded areas in both canyons had the highest levels of total vegetation cover because of the very high density of non-native invasive plants and the resulting near absence of bare ground. This is a common condition in areas that support invasive non-native grasses in Southern California (Di Tomaso et al.

2007, Kyser et al. 2007). Rather than decomposing, dead annual grasses desiccate in the hot, dry summer environment. Often successive years’ worth of grass biomass accumulates such that no bare ground remains (Kyser et al. 2007). This absence of bare ground is one important way that these invaded areas differed from the native ones. The

20 presence of bare ground between the large shrubs is a prominent characteristic of intact coastal sage scrub (Rundel 2007). Therefore, the cover of total vegetation in the native areas was greater than in the restored areas but less than in the invaded ones.

Terrestrial Arthropods

Even though the vegetation cover and species composition in the restored sites did not match that of the native sites, the terrestrial arthropod assemblage compositions were successfully restored at both Cheeseboro and Zuma canyons. The high cover of native vegetation in the restored areas was, apparently, sufficient for the colonization and persistence of arthropod assemblage compositions similar to those in the native areas at both canyons. This outcome at Cheeseboro Canyon, despite the very small sizes of the restoration areas and their isolation from source arthropod assemblages, suggests that the type of vegetation was more important for terrestrial arthropods than plot size and spatial isolation. In addition, the successful restoration of terrestrial arthropod assemblages at

Zuma Canyon suggests that the re-creation of the plant species composition of reference intact coastal sage scrub was not required for a successful arthropod restoration. These results support the Field of Dreams Hypothesis (Palmer et al. 1997) which proposes that the establishment of native vegetation and its associated structural components are sufficient to facilitate the successful restoration of animal taxa.

Structural complexity of the habitat was not measured directly in this study.

However, the shrubby structure of coastal sage scrub is very different from the dense grassiness of non-native annual grasslands (Westman 1981a, Kyser et al. 2007, Rundel

2007). Therefore, the structural aspects of the restored vegetation likely contributed to

21 the importance of native vegetation cover in the successful restoration of arthropods.

Older stands of coastal sage scrub include individuals with large numbers of dead branches (Westman 1981a), patches of bare ground, and relatively light accumulations of leaf litter (Westman 1981a, Rundel 2007). This means that areas of coastal sage scrub, whether restored or intact, have a greater diversity of microsites and other resources than do areas of invasive grassland (Kyser et al. 2007, Rundel 2007). As a result, terrestrial arthropods that require the structure of coastal sage scrub habitat colonized the restored areas in numbers that were similar to that of native areas.

Previous studies have shown that the presence of native vegetation (Williams

1993, Grimbacher and Catterall 2007, Nelson and Wydowski 2008, Nemec and Bragg

2008, Heleno et al. 2010) and the structural complexity of the habitat (Jansen 1997,

Gratton and Denno 2005, Grimbacher et al. 2007, Wodika et al. 2014, Noreika et al.

2015) are the most important characteristics related to the successful restoration of arthropod assemblages. Gratton and Denno (2005) found that restoration of the dominant plant species was accompanied by the development of structural habitat characteristics comparable to intact reference sites. Consequently, the restored structural complexity facilitated the recovery of an arthropod assemblage similar to that of native sites. Similar to the Cheeseboro Canyon results, Grimbacher and Catterall (2007) found that habitat structure was more important than vegetation age and spatial isolation for the restoration of volant rainforest beetles in reforested patches. Like the Zuma Canyon results, both

Nelson and Wydowski (2008) and Nemec and Bragg (2008) found that the presence of appropriate vegetation in restored areas was the most important factor for restoring arthropod assemblages.

The invaded areas in both canyons existed as alternative stable states in these ecosystems (Suding et al. 2004). Alternative stable states are the result of a shift in community configuration (e.g., species richness, species composition, food web structure) following disturbance (Lewontin 1969, Holling 1973, Sutherland 1974). The criteria for alternative stable states include the persistence of the new species composition for more than one generation of the dominant species, and the failure of the ecosystem to return to the previous state after the disturbance has ceased (Connell and Sousa 1983).

The non-native annual grasslands have been present in both canyons for decades (far longer than the less than one-year life cycle of these species). Further, these grasslands have not returned to coastal sage scrub since the removal of grazing animals and other agricultural disturbances at both canyons in the 1980’s, as well as the de-commissioning of the avocado grove in Zuma Canyon in 2007.

Alternative stable states have been shown to support species compositions that are different than the original ecosystems from which they have shifted (Scheffer et al. 2001,

Beisner et al. 2003, Suding et al. 2004, Suding and Hobbs 2009, Alday et al. 2013). The arthropod assemblages within the invaded areas were distinctly different from those in the restored and native areas for both canyons. The results of the canonical correspondence analysis demonstrated that the compositions of terrestrial arthropod assemblages in the invaded areas were associated with high total vegetation cover and cover of the dominant non-native plant species, and were dissimilar from the compositions in the other two areas. Additionally, both canyons had high non-native arthropod richness in the invaded sites. Four of these non-native arthropods (Bagrada hilaris, Closterotomus norvegicus, Rhopalus tigrinus, Xanthochilus saturnius) were

23 hemipterans that have documented associations with invasive plant species (B. nigra, H. incana) common to the research areas (Henry and Adamski 1998, Wheeler 2004, Scudder and Foottit 2006). Six of the ten most abundant taxa for each canyon were generalists

(Langston and Powell 1975, Hogue 1993, Resh and Cardé 2003) that had their highest abundances in the invaded areas. The high abundances of these generalists contributed to the overall high arthropod abundance at invaded sites.

Active restoration efforts were required to shift the non-native grasslands to the more natural stable state of coastal sage scrub. Suding et al. (2004) recognized that the ecological processes in stable disturbed sites are very different from those of native or reference sites and that the trajectory to recovery will probably be different (Suding et al.

2004, Suding and Hobbs 2009, Alday et al. 2013). This was the case for the restored areas in this study, where some of the restored areas required adaptive management because they were resistant to recovery (Alday et al. 2013). Prior studies have shown that restored sites in previously stable disturbed areas will likely be different from the original, or native, state (Scheffer et al. 2001, Suding et al. 2004, Alday et al. 2013). The arthropod data indicate a successful restoration and they also suggest that the restored areas are transitioning toward the stable state of native coastal sage. Canonical correspondence analysis showed that the terrestrial arthropod assemblages in the restored areas were compositionally similar to those in the native areas, but still distinctly different. While terrestrial arthropods rapidly re-colonize habitats (Jansen 1997, Burger et al. 2003, Watts and Didham 2006, Grimbacher and Catterall 2007, Noreika et al.

2015), the restored areas in Zuma Canyon were approximately five years old at the time of this study and may require more time to develop a terrestrial arthropod assemblage that

24 is more representative of the native areas. Previous studies have shown that terrestrial arthropod assemblages in restored areas become more like those of native reference areas as time since restoration efforts increases (Majer et al. 1984, Grimbacher et al. 2007,

Audino et al. 2014). Therefore, it is likely that the restored areas in both canyons will eventually support terrestrial arthropod assemblages that are even more similar to the native areas than they were at the time of this study.

The lack of significant differences in arthropod richness, abundance, Shannon index, and Pielou’s evenness among the three site types at Cheeseboro Canyon may reflect the ongoing recovery of the ecosystem following the Topanga Fire of 2005. This fire burned at low to medium intensity over the entire study area in Cheeseboro Canyon

(Witter 2006). Fire can reduce the richness and abundance of detritivores (Buckingham et al. 2015), ground beetles (Sasal et al. 2015), and web-building spiders (Foster et al.

2015), with effects still evident nine years after fire (Sasal et al. 2015). Both Westman

(1981a) and Bowler (2000) conducted long-term monitoring of coastal sage scrub recovery following wildfire. Bowler (2000) found that coastal sage scrub returned to pre- burn condition 17-20 years after a fire whereas Westman (1981a) suggested that post-fire vegetation recovery in coastal sage scrub can take up to 60 years. Given these time scales, the post-fire recovery of terrestrial arthropods associated with coastal sage scrub vegetation would have been incomplete just eight years after the fire. Therefore, it is likely that arthropod richness and abundance should be expected to progress in all three site types at for several more years.

This study was conducted during the second year of a historically severe drought

(U.S. Drought Monitor, 2016). These conditions may have resulted in terrestrial

25 arthropod populations that were not representative of arthropod assemblages in a more typical year. Even small-scale, short-term droughts can affect terrestrial arthropod distributions and abundances (Frampton et al. 2000, Lensing et al. 2005, Buccholz at el.

2012). Because of the higher temperatures and lower humidity at Cheeseboro Canyon, the impact of the drought on the plants there was more noticeable than at Zuma Canyon.

The most obvious effect of the drought was the lack of live plants in the invaded areas at

Cheeseboro Canyon. Those areas remained brown throughout the spring and summer, with little to no new growth (personal observation). This may have resulted in lower survival rates of terrestrial arthropods in the invaded sites, or migration of terrestrial arthropods away from these areas (Lensing et al. 2005, Buccholz at el. 2012). As a result, the nearby restored areas could have been supporting arthropod taxa from the invaded areas in addition to their regular arthropod assemblages (Buccholz at el. 2012).

The effect of the drought on the vegetation in Zuma Canyon was less obvious. The annual plants in the invaded areas there emerged in the spring and grew through early summer (personal observation). The impacts of the drought were ameliorated by the close proximity of the canyon to the Pacific Ocean and the resulting coastal influence

(e.g., fog cover, high humidity, cool temperatures). Nonetheless, it is possible that the drought also affected the plants and their associated arthropods in Zuma Canyon, just less so than at Cheeseboro Canyon.

Conclusions

While restored areas did not support identical terrestrial arthropod assemblages, the similarity of arthropod assemblages between the restored and native areas indicates

26 that restoration efforts at the study locations have been successful. When designing and implementing restoration projects land managers have to consider the suppression of further invasion or reinvasion by non-native species, the creation of suitable habitat for threatened and endangered species, and the efficient use of labor and budgets (Bowler

2000, Suding 2011). As a result, restoration sites may be small and spatially isolated from intact habitat. In addition, the use of native plants in combinations and/or abundances that are not found naturally in order to install native plants that will establish quickly and persist without extensive care is a regular practice in restoration projects

(Bowler 2000, Burger et al. 2003, Irvine et al. 2013). Thus, the restored areas in this study are representative of real-world restoration project outcomes. The results of this study support the Field of Dreams hypothesis (Palmer et al. 1997) and show that the cover of native vegetation in the restored areas was more important than the size of the restored areas, the distance to intact native habitat, and the replication of native plant species compositions. Similarly, Gratton and Denno 2005, Grimbacher et al. 2007,

Noreika et al. 2015 found that the practice of establishing native vegetation and its structural complexity is sufficient for the restoration of terrestrial arthropod assemblages in Spartina salt marshes, rainforests, and boreal mires, respectively. Therefore, land managers should “build” restored habitats, because arthropods will likely “come”.

The common practice of using only vegetation data to evaluate the success of restoration projects would have led to the conclusion that ecosystem restoration had not been successful at Zuma Canyon. The inclusion of terrestrial arthropod sampling allowed for a comprehensive evaluation of the progress of the restoration project. For

Cheeseboro Canyon, the arthropod data corroborated the vegetation results, which

27 allowed for a confident determination that the restoration project there was successful.

The more measures used to evaluate a restoration project lead to a better understanding of its progress and facilitate adaptive management of the project (McCoy and Mushinsky

2002, Hobbs 2007, Suding 2011). Adding arthropod assemblage evaluation to the common practice of vegetation monitoring will help land managers to better evaluate restoration project outcomes.

Cheeseboro Canyon

Zuma Canyon

Figure 1. The location of study sites in the Santa Monica Mountains National Recreation Area: Zuma Canyon and Cheeseboro Canyon.

p=0.07 b b

Figure 2. Mean plant species richness across all plots for the three site types in Cheeseboro Canyon. Means with different letters are significantly different. Bars are standard errors.

b p=0.001

a a

Figure 3. Mean plant species richness across all plots for three site types in Zuma Canyon. Means with different letters are significantly different. Bars are standard errors.

a Total Vegetation A p<0.001 c b

b b B Native Species p<0.001

C Salvia leucophylla b p=0.12

Figure 4. Percentages of mean vegetation cover (A), mean native species cover (B), and mean Salvia leucophylla cover (C) at three site types in Cheeseboro Canyon. The invaded sites had no native species, including S. leucophylla. Means with different letters are significantly different. Bars are standard errors.

a Total Vegetation p=0.005 c A b

b b B Native Species p<0.001

c C Salvia mellifera p=0.002

Figure 5. Percentages of mean vegetation cover (A), mean native species cover (B), and mean Salvia mellifera cover (C) at three site types in Zuma Canyon. The invaded sites had no native species, including S. mellifera. Means with different letters are significantly different. Bars are standard errors.

Table 1. Vegetation cover data for each plot in three types of sites at Cheeseboro Canyon. Numbers are percentage of cover for each species. Unknown grass was the same taxon for all plots in which it occurred.

Invaded Restored Native Plant Species 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 6 7 8 Natives: Artemisia californica - - - - - 59 19 31 35 21 2 2 1 2 2 69 16 30 Hazardia squarrosa ------3 44 39 Malacothamnus fasciculatus - - - - - 10 ------Salvia leucophylla - - - - - 16 64 37 40 45 93 93 94 80 92 13 1 14 Dead woody material ------1 - 14 2 Invasives: Bromus madritensis 90 93 96 87 99 ------13 - Marrubium vulgare ------3 ------Unknown grass 4 7 1 ------

Table 2. Vegetation cover data for each plot in three types of sites at Zuma Canyon. Numbers are percentage of cover for each species. Unknown grass was the same taxon for all plots in which it occurred.

Invaded Restored Native Plant Species 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 Natives: Artemisia californica 1 - - - - 5 21 9 13 3 - - - 27 64 Artemisia douglasiana - - - - - 8 13 1 ------Baccharis pilularis - - - - - 45 16 49 39 62 - - 19 - - Baccharis salicifolia ------10 - - - - - Eriogonum cinereum ------1 1 Eriogonum elongatum 1 ------Eriogonum fasciculatum ------3 - Hesperoyucca whipplei ------1 ------Isocoma menziesii - - - - - 2 - 1 - 1 - - - - - Malacothamnus fasciculatus ------6 - 10 1 - - - - - Malosma laurina ------4 - - Peritoma arborea 4 - - - - 3 - 3 ------Salvia leucophylla - - - - - 24 4 27 7 7 - - - 25 13 Salvia mellifera - - - - - 1 17 1 17 3 84 88 49 30 13 Sambucus nigra ------10 - - - Dead woody material ------8 - 19 - 1 Invasives: Avena barbata 26 16 - 46 90 ------Avena fatua 24 5 66 ------Bromus diandrus 44 79 4 ------Euphorbia terracina - - - 4 ------Phalaris aquatica - - 30 3 2 - - 1 ------Stipa miliacea - - - 39 7 ------1 -

Unknown grass ------1 - 5 3 1 - 7 - -

Number of TaxaNumber of

Number of Plots

Figure 6. Taxa accumulation curve for Cheeseboro Canyon showing that pitfall sampling effort was sufficient for the accurate estimation of terrestrial arthropod species richness. Dashed lines indicate the 95% confidence interval.

Number of TaxaNumber of

Number of Plots

Figure 7. Taxa accumulation curve for Zuma Canyon showing that pitfall sampling effort was sufficient for the accurate estimation of terrestrial arthropod species richness. Dashed lines indicate the 95% confidence interval.

Table 3. Canonical correspondence coefficients for the five environmental variables showing their contribution to the resulting axes and the percentage of total variation explained by each axis.

Canonical Coefficients Cheeseboro Canyon Axis1 Axis2 Axis3 Total Vegetation Cover 0.65 -0.44 -1.50 Native Vegetation Cover -3.10 -4.97 23.58 Plant Species Richness -0.02 -0.71 0.94 Saliva leucophylla cover -1.30 0.03 0.63 Bromus madritensis cover -4.09 -4.26 25.94

Eigenvalue 0.33 0.28 0.12 Percent variance explained 19.20 16.00 6.80

Zuma Canyon Axis1 Axis2 Axis3 Total Vegetation Cover 0.04 0.80 0.03 Native Vegetation Cover -0.79 -0.10 -0.08 Plant Species Richness -0.17 0.33 -0.40 Salvia mellifera cover -0.16 0.15 0.77 Avena barbata cover 0.03 -0.98 0.09

Eigenvalue 0.40 0.15 0.11 Percent variance explained 29.30 11.00 8.50

Cheeseboro Canyon 3 Arthropod taxa

Invaded plots 2.5

Restored plots Coniontis 2 Anthrenus Native plots

1.5 Cryptorhopalum Spider29 Spider15 1 B. madritensis cover

0.5 total vegetation cover

0 -1.8 -1.4 -1 -0.6 -0.2 0.2 0.6 1 1.4 L. humile Gelis1 L.vexator S. leucophylla Leafhopper14 -0.5 cover plant species native -1 vegetation richness cover Dicronaptycha -1.5 Encyrtidae7

-2

Figure 8. Canonical correspondence analysis ordination diagram for Cheeseboro Canyon showing the distribution of terrestrial arthropods, sample plots, and environmental variables.

Table 4. Arthropod taxa with the 10 highest loadings for both axes from Cheeseboro Canyon and the environmental variables they were associated with in canonical correspondence analysis. The taxon Encyrtidae 7 had loadings in the top 10 for both axes.

Taxa name Axis 1 loading Axis 2 loading Environmental variable Feeding Group Linepithema humile -1.60 -0.23 Salvia leucophylla cover Omnivore Gelis1 -1.59 -0.33 Salvia leucophylla cover Parasitoid Orgerius2 -1.51 -0.45 Salvia leucophylla cover Herbivore Leafhopper16 -1.39 -0.35 Salvia leucophylla cover Herbivore Ammosphex -1.34 -0.14 Salvia leucophylla cover Parasitoid Scelionidae1 -1.33 -0.20 Salvia leucophylla cover Parasitoid Encyrtidae7 1.31 -1.61 plant species richness Parasitoid Lutzomyia vexator -1.20 -0.45 Salvia leucophylla cover Omnivore Leafhopper14 -1.19 -0.46 Salvia leucophylla cover Herbivore Pompilid1 -1.19 -0.18 Salvia leucophylla cover Parasitoid Coniontis 0.55 2.15 Bromus madritensis cover Detritivore Anthrenus 0.42 1.92 Bromus madritensis cover Herbivore Tachinidae 0.31 1.54 Bromus madritensis cover Nectivore Cryptorhopalum 0.29 1.45 Bromus madritensis cover Detritivore Gnaphosid6 0.26 1.40 Bromus madritensis cover Predator Dicranoptycha 1.17 -1.40 plant species richness Predator Tenebrionidae3 0.19 1.39 Bromus madritensis cover Detritivore Spider29 0.42 1.30 Bromus madritensis cover Predator Spider15 0.38 1.13 Bromus madritensis cover Predator

Zuma Canyon 1.5

1 B.hilaris Ceraphronidae2 0.5 Ceraphronidae7 S. mellifera total vegetation cover native cover 0 vegetation -1.5 -1 -0.5 0 0.5 1 1.5 cover plant species -0.5 Spider43 R. ventralis richness A. barbata -1 cover Scelionidae3 Therevidae Tachinidae Oxyopidae P. diabolicus Diapriidae6 -1.5 Leafhopper9 Linyphiid2 Myrmosula Leafhopper8 Lycosidae1 X.saturnius Arthropod taxa -2 Invaded plots -2.5 Restored plots Native plots -3

-3.5 Figure 9. Canonical correspondence analysis ordination diagram for Zuma Canyon showing the distribution of terrestrial arthropods, sample plots, and environmental variables.

Table 5. Arthropod taxa with the 10 highest loadings for both axes from Zuma Canyon and the environmental variables they were associated with in canonical correspondence analysis. The species Xanthochilus saturnius had loadings in the top 10 for both axes.

Taxa name Axis 1 loading Axis 2 loading Environmental variable Feeding Group Therevidae 1.21 -1.03 Avena barbata cover Nectivore Bagrada hilaris 1.16 0.98 total vegetation cover Herbivore Ceraphronidae7 1.15 0.56 total vegetation cover Parasitoid Xanthochilus saturnius 1.14 -1.90 Avena barbata cover Granivore Scelionidae3 1.14 -0.95 Avena barbata cover Parasitoid Rhynocoris ventralis 1.13 -0.63 Avena barbata cover Predator Spider43 1.12 -0.52 Avena barbata cover Predator Ceraphronidae2 1.10 0.72 total vegetation cover Parasitoid Eupelmidae4 1.07 0.50 total vegetation cover Parasitoid Lygaeidae1 1.06 0.47 total vegetation cover Granivore Lycosidae1 0.23 -1.78 Avena barbata cover Predator Myrmosula 0.19 -1.75 Avena barbata cover Parasitoid Leafhopper8 0.56 -1.72 Avena barbata cover Parasitoid Linyphiid2 0.92 -1.56 Avena barbata cover Predator Leafhopper9 0.18 -1.55 Avena barbata cover Herbivore Diapriidae6 0.99 -1.38 Avena barbata cover Parasitoid Phloeodes diabolicus 0.20 -1.32 Avena barbata cover Fungivore Oxyopidae 0.97 -1.19 Avena barbata cover Predator Tachinidae -0.20 -1.14 Avena barbata cover, Nectivore plant species richness

A p=0.83

Figure 10. Mean terrestrial arthropod richness (A) and abundance (B) per plot at three site types from Cheeseboro Canyon. Bars are standard errors. P-values are based on analysis of square-root transformed richness and log10 transformed abundance.

A p=0.22

a B p=0.01 a

Figure 11. Mean terrestrial arthropod richness (A) and abundance (B) per plot at three site types from Zuma Canyon. Means with different letters are significantly different. Bars are standard errors. Bars are standard errors. P-values are based on analysis of square-root transformed richness and log10 transformed abundance.

A p=0.96

B p=0.79

Figure 12. Shannon index (A) and Pielou’s evenness (B) values for terrestrial arthropods at three site types from Cheeseboro Canyon. Bars are standard errors.

A p=0.07 b a a

B p=0.04 b

a a

Figure 13. Shannon index (A) and Pielou’s evenness (B) values for terrestrial arthropods at three site types from Zuma Canyon. Means with different letters are significantly different. Bars are standard errors.

p=0.39

Figure 14. Mean percentages of non-native terrestrial arthropod taxa at Cheeseboro Canyon. Bars are standard errors.

a p=0.04

b b

Figure 15. Mean percentages of non-native terrestrial arthropod taxa at Zuma Canyon. Means with different letters are significantly different. Bars are standard errors.

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Appendix A

Complete terrestrial arthropod taxa list for Cheeseboro Canyon and Zuma Canyon. Morphospecies are taxa that were not identified beyond the level of order. For each canyon, the presence of a given taxa is indicated by ‘X’ and absence is indicated by ‘-‘. Rare taxa are denoted as ‘R’ and non-native taxa are denoted as ‘N’.

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Araneae Agelenidae Hololena Predator X X Hololena2 Predator X X Dysderidae Dysdera crocata Predator N N Gnaphosidae Gnaphosidae1 Predator X X Gnaphosidae2 Predator X X Gnaphosidae3 Predator X X Gnaphosidae4 Predator X X Gnaphosidae5 Predator X X Gnaphosidae6 Predator X X Gnaphosidae7 Predator X X Gnaphosidae8 Predator X X Gnaphosidae9 Predator R X Gnaphosidae10 Predator X X Gnaphosidae11 Predator X X Gnaphosidae12 Predator X X Gnaphosidae13 Predator R X Gnaphosidae14 Predator - R Gnaphosidae15 Predator X - Linyphiidae Linyphiidae1 Predator R X Linyphiidae2 Predator - x Lycosidae Hogna Predator X X Lycosidae1 Predator X X Lycosidae2 Predator R R Schizocosa mccooki Predator X X TinyLycosidae Predator X X Oonipidae Escaphiella hespera Predator X R Oxyopidae Oxyopidae Predator X X Philodromidae Titanebo Predator X R Philodromidae1 Predator X X Salticidae Salticidae1 Predator X X Salticidae2 Predator X X Salticidae3 Predator X X Salticidae4 Predator X X Tengellidae Titiotus shantzi Predator R -

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Thomisidae Thomisidae Predator X X Morphospecies Big Spider2 Predator - R Big Spider3 Predator - R Big Spider4 Predator X X Big Spider5 Predator - R Lanky Spider Predator X - Long Narrow Spider Predator X R Spider2 Predator X X Spider3 Predator X X Spider6 Predator X X Spider7 Predator X X Spider9 Predator X X Spider12 Predator X X Spider15 Predator X X Spider18 Predator R X Spider20 Predator - X Spider21 Predator X X Spider22 Predator X - Spider23 Predator X X Spider25 Predator - X Spider26 Predator R R Spider28 Predator X R Spider30 Predator R X Spider32 Predator R X Spider34 Predator R - Spider37 Predator R X Spider39 Predator X X Spider40 Predator X X Spider42 Predator - X Spider43 Predator R X Spider44 Predator X X Spider45 Predator X X Spider47 Predator X X Spider48 Predator R X Spider49 Predator - X Spider51 Predator X X Spider52 Predator - R Spider54 Predator R - Spider55 Predator - R Black Spider Predator - R White Spider Predator - R

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Archaeognatha Machilidae Bristletails Omnivore X X Blattodea Ectobiidae Parcoblatta americana Detritivore X X Ceoleoptera Anthicidae Ischyropalpus Detritivore R X Notoxus Detritivore - X Omonadus Detritivore - R Buprestidae Chrysobothris Herbivore R - Cantharidae Cantharidae Herbivore R R Cantharis Herbivore - X Pacificanthia consors Herbivore R - Carabidae Amara Predator X - Carabidae with Color Predator X R Harpalus caliginosus Predator R - Neocalathus Predator X X Notiophilus semiopacus Predator R - Pterostichus Predator X X Scaphinotus punctatus Predator R X Tiny Carabidae Predator - X Cerambycidae Neoclytus tenuiscriptus Herbivore X - Chrysomelidae Acanthoscelides Herbivore R X Alticinae Herbivore - R Chaetocnema Herbivore X X Pachybrachis Herbivore R X Phyllotreta Herbivore X X Psylliodes Herbivore X R Zabrotes densus Herbivore X - Cleridae Cymatodera Predator - R Phyllobaenus Predator R R Coccinelidae Coccinelidae Predator - X Hyperaspidius near - R comparatus Predator Corylophidae Sericoderus Fungivore R R Cryptophagidae Cryptophagidae Fungivore - R Curculionidae Curculionidae Herbivore - X Sphenophorus phoeniciensis Herbivore R - Dermestidae Anthrenus Pollenivore X X Cryptorhopalum Detritivore X X Dermestes undulatus Detritivore - N, R Trogoderma Detritivore X X

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Elateridae Melanotus longulus Herbivore X X Near Heteroderes Herbivore R X Elateridae3 Herbivore X X Endomychidae Aphorista morosa Fungivore R - Histeridae Xerosaprinus1 Predator X X Xerosaprinus2 Predator X R Hydrophilidae Hydrophilidae Omnivore - R Latridiidae Latridiidae Detritivore X X Melandryidae Melandryidae Detritivore - R Melandryidae2 Detritivore - X Melyridae Attalus1 Herbivore - R Attalus2 Herbivore - R Collops Herbivore - R Melyridae Herbivore X X Melyridae2 Herbivore R X Mordellidae Mordellidae Herbivore X X Nitidulidae Meligethes Herbivore - R Ptiliidae Ptiliidae Fungivore - R Anobiidae1 Detritivore - X Anobiidae2 Detritivore X X Anobiidae3 Detritivore - R Lasioderma Detritivore X X Niptus Detritivore X X Ptinus Detritivore X - Scarabaeidae Aphodius Detritivore X - Pleurophorus caesus Detritivore N, R - Silphidae Nicrophorus nigrita Predator - R Staphylinidae Dinothenarus luteipes Predator - X Staphylinidae1 Predator X X Staphylinidae3 Predator R X Staphylinidae4 Predator X X Staphylinidae5 Predator X X Tenebrionidae Alleculinae Detritivore X X Apocrypha Detritivore X - Coelocnemis magna Detritivore X X Coniontis Detritivore X - Eleodes acuticaudus Detritivore X X Eleodes dentipes Detritivore X X Eleodes littoralis Detritivore - R Eleodes osculans Detritivore X X Nyctoporis carinata Detritivore X X

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Tenebrionidae Tenebrionidae2 Detritivore - X Tenebrionidae3 Detritivore X X Zopheridae Phloeodes diabolicus Fungivore - X Phloeodes plicatus Fungivore - X Rhagodera tuberculata Fungivore - R Morphospecies Beetle1 Omnivore - X Beetle3 Omnivore X R Tiny beetle Omnivore - X Tiny round beetle Omnivore R X Coleoptera Larvae Omnivore X X Chilopoda Morphospecies Chilopoda Predator X X Dermaptera Anisolabididae Euborellia annulipes Omnivore - N Forficulidae Forficula auricularia Omnivore N N Diplopoda Polyxenidae Polyxenus Detritvore R - Morphospecies Diplopoda Detritvore - R Diplopoda2 Detritvore - R Diptera Anthomyiidae Anthomyiidae Omnivore X X Anthomyiidae2 Omnivore X - Anthomyiidae3 Omnivore X - Asilidae Asilidae Predator X - Leptogaster Predator R - Machimus occidentalis Predator - X Bombyliidae Apolysis Nectivore - R Bombyliidae Nectivore - R Tiny Bombyliidae Nectivore X R White Bombyliidae Nectivore - R Calliphoridae Calliphoridae Detritivore X X Cecidomyiidae Cecidomyiidae Omnivore X X Ceratopagonidae Ceratopagonidae Sanguivore X - Chloropidae Chloropidae Omnivore X X Chyromyidae Chyromyidae Predator X R Culicidae Culicidae Sanguivore X - Culicidae2 Sanguivore R - Dolichopodidae Dolichopodidae Predator X X Dolichopodidae2 Predator - X Dolichopodidae3 Predator R - Empididae Empididae Omnivore R R Empididae2 Omnivore R R

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Empididae Empididae3 Omnivore X X Empididae4 Omnivore X R Fanniidae Fanniidae Detritivore X X Heleomyzidae Heleomyzidae Detritivore X X Heleomyzidae2 Detritivore X X Heleomyzidae3 Detritivore - R Trixoscelis Detritivore X X Suillia Detritivore - R Milichiidae Milichiidae Detritvore - R Muscidae Muscidae Detritivore R R Mycetophilidae Mycetophilidae Fungivore X X Mythicomyiidae Glabellula Predator R X Phoridae Phoridae Omnivore X X Yellow Phoridae Omnivore X X Pipunculidae Tomosvaryella Predator X - Psychodidae Lutzomyia vexator Omnivore X R Psychodidae Omnivore - X Sarcophagidae Sarcophagidae Parasitoid X X Scatopsidae Swammerdamella Detritivore - R Sciaridae Sciaridae Fungivore X X Tachinidae Tachinidae Parasitoid X X Tephiritidae Tephritis araneosa Herbivore - X Therevidae Therevidae Nectivore X X Tipulidae Dicranoptycha Predator X X Tipula californica Predator R - Tipula lygropis Predator - R Tipula praecisa Predator R - Tipula species Predator - R Vermileonidae Vermileo Predator - R Morphospecies Acalypterate2 Omnivore X - Yellow Fly Omnivore R X Yellow Fly2 Omnivore R R Embiodea Anisembiidae Chelicera rubra Detritvore X X Entomobryomorpha Morphospecies Entomobryomorpha Omnivore X X Hemiptera Aleyrodidae Herbivore X R Aleyrodidae Aleyrodidae2 Herbivore X - Aphididae Aphididae Herbivore X X Eriosomatinae Herbivore R R Berytidae Berytidae Predator R R Pronotacantha Herbivore - R

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Cicadellidae Black Leafhopper Herbivore R X Cochlorhinus Herbivore R - Colladonus geminatus Herbivore X X Euscelis variegatus Herbivore - X Leafhopper2 Herbivore R - Leafhopper3 Herbivore X - Leafhopper4 Herbivore - R Leafhopper5 Herbivore X X Leafhopper6 Herbivore X - Leafhopper7 Herbivore X R Leafhopper8 Herbivore X X Leafhopper9 Herbivore X X Leafhopper11 Herbivore X - Leafhopper14 Herbivore X X Leafhopper15 Herbivore X X Leafhopper16 Herbivore X X Leafhopper17 Herbivore X X Leafhopper18 Herbivore R X Leafhopper19 Herbivore - X Leafhopper20 Herbivore X X Leafhopper21 Herbivore X - Leafhopper22 Herbivore X - Leafhopper23 Herbivore R - Leafhopper24 Herbivore - R Leafhopper25 Herbivore R - Deltocephalinae Nymphs Herbivore X X Cixiidae Cixius Herbivore R X Clastopteridae Clastoptera atripicata Herbivore - X Coccoidea Coccoidea Herbivore X X Delphacidae Delphacidae Herbivore X X Dictyopharidae Orgerius Herbivore X X Orgerius2 Herbivore X - Enicocephalidae Enicocephalidae Predator - R Nesenicocephalus Predator - R Geocoridae Geocorinae Predator - R Issidae Danepteryx1 Herbivore X X Danepteryx2 Herbivore X - Danepteryx3 Herbivore - X Kinnaridae Kinnaridae Herbivore X X Lygaeidae Lygaeidae1 Granivore X X Lygaeidae2 Granivore X X Lygaeidae3 Granivore X X

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Lygaeidae Lygaeidae4 Granivore X X Lygaeidae5 Granivore - X Lygaeidae6 Granivore R - Membracidae Parantonae hispida Herbivore R R Philya californiensis Herbivore - R Miridae Closterotomus norvegicus Herbivore - N, R Miridae1 Herbivore X - Miridae2 Herbivore - R Miridae3 Herbivore X R Miridae4 Herbivore X X Miridae5 Herbivore R X Miridae6 Herbivore - R Miridae7 Herbivore R - Miridae8 Herbivore X - Miridae9 Herbivore X X Miridae10 Herbivore R - Miridae11 Herbivore X X Miridae12 Herbivore R X Nabidae Hoplistoscelis heidemanni Predator X X Nabidae Predator - R Pentatomidae Bagrada hilaris Herbivore - N Murgantia histrionica Herbivore - R Psyllidae Psyllidae Herbivore X X Pyrrhocoridae Scantius aegyptius Granivore - N Reduviidae Apiomeris californicus Predator X X Ploiaria Predator R X Reduviidae2 Predator R - Reduviidae4 Predator R - Reduviidae6 Predator - R Rhynocoris ventralis Predator X - Sinea Predator - R Rhopalidae Arhyssus Granivore - R Rhopalus tigrinus Granivore - N, R

X - Rhyparochromidae Emblethis vicarius Granivore Malezonotus rufipes Granivore R R Ozophora depicturata Granivore - R Scolopostethus thomsoni Granivore R R Xanthochilus saturnius Granivore - N Scutelleridae Eurygaster Herbivore R R Tingidae Tingidae2 Herbivore R R Morphospecies Hemiptera Nymph Omnivore X X

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Hymenoptera Andrenidae Calliopsis Nectivore/Pollenivore R - Aphelinidae Aphelinidae Predator - R Apidae Apis mellifera Nectivore/Pollenivore N, R X Bombus vosnesenskii Nectivore/Pollenivore - X Ceratina acantha Nectivore/Pollenivore - X Ceratina arizonensis Nectivore/Pollenivore - X Habropoda tristissima Nectivore/Pollenivore - R Bethylidae Bethylidae Parasitoid X X Bethylidae2 Parasitoid - X Braconidae Braconidae1 Parasitoid R - Braconidae2 Parasitoid R X Braconidae3 Parasitoid X X Braconidae4 Parasitoid X X Braconidae5 Parasitoid - R Braconidae6 Parasitoid X X Braconidae7 Parasitoid R R Braconidae8 Parasitoid X R Braconidae9 Parasitoid X X Chelonus Parasitoid X X Ceraphronidae Ceraphronidae Parasitoid X - Ceraphronidae2 Parasitoid X X Ceraphronidae3 Parasitoid X X Ceraphronidae4 Parasitoid X R Ceraphronidae5 Parasitoid - X Ceraphronidae6 Parasitoid X X Ceraphronidae7 Parasitoid X X Ceraphronidae8 Parasitoid X X Ceraphronidae9 Parasitoid R X Ceraphronidae10 Parasitoid X - Ceraphronidae11 Parasitoid X X Ceraphronidae12 Parasitoid - X Chalcididae Chalcididae Parasitoid R X Chalcididae2 Parasitoid X X Hockeria Parasitoid X X Hockeria unipunctatipennis Parasitoid R R Chrysididae Chrysididae Parasitoid - R Chrysididae2 Parasitoid - X Chrysididae Omalus Parasitoid R R Crabronidae Crabronidae2 Parasitoid X X Crabronidae3 Parasitoid R X Crabronidae4 Parasitoid R R

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Crabronidae Larrini Parasitoid X R Pemphredoninae Parasitoid R X Diapriidae Diapriidae Parasitoid - X Diapriidae2 Parasitoid X X Diapriidae3 Parasitoid X X Diapriidae4 Parasitoid X X Diapriidae5 Parasitoid X R Diapriidae6 Parasitoid X X Dryinidae Gonatopodinae Parasitoid R R Dryinid2 Parasitoid X - Encyrtidae Encyrtidae Parasitoid X - Encyrtidae2 Parasitoid X X Encyrtidae3 Parasitoid X X Encyrtidae4 Parasitoid - R Encyrtidae5 Parasitoid X X Encyrtidae6 Parasitoid X X Encyrtidae7 Parasitoid X X Encyrtidae8 Parasitoid - R Encyrtidae9 Parasitoid X X Near Encyrtidae Parasitoid X X Near Encyrtidae2 Parasitoid X - Tetracnemus Parasitoid R R Tetracnemus2 Parasitoid - R Eulophidae Eulophidae Parasitoid X X Eupelmidae Eupelmidae Parasitoid - R Eupelmidae2 Parasitoid - X Eupelmidae3 Parasitoid R X Eupelmidae4 Parasitoid X X Figitidae Eucolinae Parasitoid R R Figitidae2 Parasitoid R - Figitidae3 Parasitoid R - Figitidae4 Parasitoid X X Formicidae Camponotus semitestaceus Omnivore X X Crematogaster californica Omnivore X X Hypoponera Herbivore - X Linepithema humile Omnivore N N Neivamyrmex leonardi Predator X R Pheidole hyatti Omnivore X X Formicidae Tapinoma sessile Omnivore X X Halictidae Dufourea Nectivore/Pollenivore R - Halictidae1 Nectivore/Pollenivore X X Halictidae2 Nectivore/Pollenivore R -

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Ichneumonidae Gelis1 Parasitoid X - Gelis2 Parasitoid X X Gelis3 Parasitoid X R Ichneumonidae Parasitoid R - Ichneumonidae2 Parasitoid - R Ichneumonidae3 Parasitoid X - Ichneumonidae4 Parasitoid R - Megachilidae Osmia Nectivore/Pollenivore R - Osmia2 Nectivore/Pollenivore - X Megaspilidae Megaspilidae Parasitoid - R Mutilidae Mutilidae Nectivore X R Mutilidae2 Nectivore - X Mymaridae Mymaridae Parasitoid R R Mymaridae2 Parasitoid X X Mymaridae3 Parasitoid X X Mymaridae4 Parasitoid X X Mymaridae5 Parasitoid X X Mymaridae6 Parasitoid - R Myrmosidae Myrmosula Parasitoid - X Perilampidae Perilampidae Parasitoid R R Platygastridae Platygastridae Parasitoid X - Platygastridae2 Parasitoid X X Platygastridae3 Parasitoid X X Pompilidae Ammosphex Parasitoid X R Pompilidae1 Parasitoid X X Pompilidae3 Parasitoid X X Pompilidae5 Parasitoid R R Tachypompilus Parasitoid R X Tiny Pompilidae Parasitoid - X Pteromalidae Pteromalidae Parasitoid R X Pteromalidae2 Parasitoid X X Pteromalidae3 Parasitoid X X Pteromalidae4 Parasitoid X X Pteromalidae5 Parasitoid R X Pteromalidae6 Parasitoid - X Pteromalidae7 Parasitoid X X Pteromalidae8 Parasitoid - R Pteromalidae9 Parasitoid X X Pteromalidae10 Parasitoid X X Pteromalidae11 Parasitoid R - Scelionidae Scelionidae Parasitoid X X Scelionidae2 Parasitoid X R

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Scelionidae Scelionidae3 Parasitoid X X Scelionidae4 Parasitoid X X Scelionidae5 Parasitoid X R Scelionidae6 Parasitoid X X Scelionidae7 Parasitoid X X Signiphoridae Signiphoridae Parasitoid X X Isopoda Armadillidiidae Armadillidium vulgare Detritivore N N Porcellionidae Porcellio laevis Detritivore N N, R Ixodida Ixodidae Ticks Sanguivore X X Lepidoptera Gelechiidae Gelechiidae Herbivore X X Geometridae Geometridae Herbivore X - Geometridae Herbivore R - Noctuidae Noctuidae Herbivore R R Nymphalidae Vanessa cardui Nectivore - R Morphospecies Butterfly Nectivore - R Large Moth Nectivore - R Moth1 Nectivore X X Moth2 Nectivore R R Moth3 Nectivore R - Moth4 Nectivore X X Lepidoptera Larvae Herbivore R X Mantodea Mantidae Litaneutria minor Predator X R Neuroptera Chrysopidae Chrysopidae Predator - X Coniopterygidae Semidalis Predator - R Cydnidae Cydnidae Predator - R Hemerobiidae Hemerobiidae Predator - X Myrmeleontidae Myrmeleontidae Predator - R Opiliones Morphospecies Opiliones1 Predator - X Opiliones2 Predator - X Morphospecies Harvestman1 Predator X X Harvestman2 Predator X X Harvestman4 Predator - R

Oribatida Morphospecies Oribatida Detritivore X X Shield Mite Predator R -

Order, Family Taxon Name Feeding Group Cheeseboro Zuma Orthoptera Acrididae Chloealtis gracilis Herbivore X - Chimarocephala pacifica Herbivore X R Cyrtacanthacridinae Herbivore X X Grasshopper1 Herbivore R X Schistocerca nitens Herbivore X - Trimerotropis pallidipennis Herbivore X - Gryllidae Gryllus lineaticeps Omnivore X - Rhaphidophoridae Ceuthophilus Omnivore X X Pristoceuthophilus Omnivore X X Stenopelmatidae Stenopelmatis Detritivore X X Tettigoniidae Decticita balli Herbivore X - Katydid1 Herbivore X X Phthiraptera Phthiraptera Sanguivore - R Poduromorpha Poduromorpha Omnivore X X Pseudoscorpionida Pseudoscorpion Predator X X Psocoptera Psocoptera Fungivore X X Raphidioptera Raphidiidae Raphidiidae Predator R R Siphonaptera Siphonaptera Sanguivore X X Solifugae Eremobatidae Solifugidae1 Predator - X Solifugidae2 Predator X X Symphypleona Symphypleona Omnivore X X Thysanoptera Aeolothripidae Aeolothrips Omnivore X X Thripidae Thysanoptera Herbivore X X Trombidiformes

Bdellidae Snout Mites Predator X X Morphospecies Ticky Mites Predator X X Spider Mite Predator X X Zygentoma Lepismatidae Lepismatidae Omnivore X X