SUPPLEMENTARY INFORMATION

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1 Supplementary Methods 1 Food we metrics. Weighted, quantitative versions of Linkage Density, Connectance, Vulneraility and Generality, ased on information theory 10,11 were calculated. Quantitative metrics are weighted to incorporate the total inflow and outflow of individuals per species 10. These metrics are more roust to sampling differences than their qualitative counterparts and they have lower sensitivity for detecting differences etween systems 11, making them more conservative when comparing haitats 11. Each metric incorporates the diversity of individuals comprising the prey (H N, the diversity of inflows) and of that going to the consumers (H P, the diversity of outflows) for each species k. Following Bersier and others 10, these were calculated as: H S ik N, k = log 2 i= 1 k ik k S kj H P, k = log 2 j= 1 k kj k Within the parasitoid/host matrix, k and k represent the column sum and row sum, respectively, i.e. the total numer of individuals attacked y, and attacking taxon k. This requires the assumption that iomass of all species is identical. The food we metrics are ased on the reciprocals 11 of H N,k and H P,k : H N, k 2 nn. k = if k = 0 O H P, k 2 np. k = if k = 0 O 1

2 In non-quantitative food wes, linkage density (L.D.) is the numer of links (trophic interactions) divided y the numer of species. A quantitative measure of L.D. is calculated as 10 : LD q s s 1 k = np, k + 2 k 1 k 1 n k N, k = = Quantitative, weighted food we connectance was calculated as LD q /s, where s is the numer of species in the we. Generality (G) and Vulneraility (V) are, respectively, the mean numer of host species per parasitoid and the mean numer of parasitoid species per host. Quantitative versions 10 were calculated as: G V q q = = s k nn, k k = 1 s k np, k k = 1 Because these metrics are relatively insensitive to differences in the evenness of the distriution of link magnitude 11, and ecause differences in interaction evenness may e ecologically important 3-7, we calculated an additional measure which we term interaction evenness, I.E.: I.E. = p i log ( p ) log 2 2 N i where p i is the proportion of the total numer of parasitoid-host interactions (N) represented y interaction i. This is consistent with the other quantitative food we metrics, which are also ased on the Shannon index H measured in ase 2. Parasitism rate was defined as the proportion of host individuals parasitised or kleptoparasitised. 2

3 The numer of compartments in a food we was defined as the numer of suwes with no connection to any other suwe, considering only suwes that include oth hosts and parasitoids. Heterogeneity in the size of different suwes was represented y a measure of compartment diversity 22 : n C.D. = exp p i ln p i i 1 where p i is the fraction of all host and parasitoid species in the ith of n compartments. This is the exponential form of the Shannon-Wiener diversity index. Supplementary Methods 2: Melittoia acasta host evenness. The evenness of hosts used y the eulophid parasitoid Melittoia acasta was calculated as the Shannon diversity index divided y the log of sample size (see calculation of Interaction Evenness in Supplementary Methods 1 aove). Host evenness was compared across haitat types using analysis of variance (ANOVA), Post hoc comparisons were made using Tukey s unequal N HSD test. One forest and one aandoned coffee plot were excluded from analyses as no M. acasta was oserved in these plots. Supplementary Methods 3: Testing the effects of haitat type and parasitism rates of Anthidium sp. on parasitism of Megachile sp. 1. Anthidium sp. is the host species most heavily parasitised y M. acasta, with aout 32.6% of all Anthidium sp. larvae dying in this way. Megachile sp. 1 is the second most heavily attacked (11.6% of larvae), so we tested whether high rates of parasitism on Anthidium sp. released Megachile sp. 1 from parasitism y M. acasta. For this model, we treated the proportion of Anthidium sp. larvae parasitized per plot as a continuous 3

4 predictor, and the proportion of Megachile sp. 1 parasitised y M. acasta as the response. Because parasitism rates of Anthidium sp. varied across haitats, we took a conservative approach, and included haitat type first in the model with Type I SS. This allowed us to determine the direct effect of Anthidium sp. parasitism, following removal of variation explained y differences in parasitism rates among haitats. As parasitism rates of other host species, less heavily attacked y M. acasta may also affect parasitism of Megachile sp. 1, we included parasitism rates of the remaining five most aundant host species as multivariate response variales in a General Linear Model (MANCOVA), to allow a more conservative test. 4

5 Supplementary Tale 1: Effects of haitat type on qualitative (inary) food we metrics from independent GLMs. Model 1 Model 2 Variale F 4,41 P r 2 F 4,41 P r 2 Interaction richness < < Linkage density < < Generality < Vulneraility < < Connectance < < The qualitative metrics use inary presence/asence data for interactions. Model 1 has haitat type entering the model first, efore parasitoid and host diversity. Model 2 has haitat type entering last, after removal of variation explained y parasitoid and host diversity. The variales tested were Interaction richness (numer of parasitoid-host links, L), Linkage density (L/s), where s is the numer of species in the we, Connectance (L/s 2 ), Generality (L/s Parasitoid ) and Vulneraility (L/s Host ). A Bonferonni corrected α of 0.01 was used to determine significance. Significant effects in old. 5

6 Supplementary figure 1: Variation in qualitative food we parameters across haitats. All metrics were significantly higher in rice and pasture than in the remaining haitat types. Total host aundances (numer of host individuals recorded) across the study were as follows: Rice 7628, Pasture 8415, Coffee agroforest 2949, Aandoned coffee agroforest 1399, Forest

7 Supplementary Tale 2: Results of general linear models following stepwise removal of hosts in order of total aundance. 2A:Vulneraility tale Model 1 (Type 1 st ) Model 2 (Type last) Host removal d.f. F P F P - Anthidium sp. 4, Pseudodynerus sp. 4, Trypoxylon sp.2 4, Zeta sp. 4, Sphecidae Gen. sp. 2 4, Neofidelia sp. 4, Trypoxylon sp.1 4, Megachile sp.1 4,

8 2B: Evenness tale Model 1 (Haitat type 1 st ) Model 2 (Haitat type last) Host removal d.f. F P F P - Anthidium sp. 4, Pseudodynerus sp. 4, Trypoxylon sp.2 4, Zeta sp. 4, Sphecidae Gen. sp. 2 4, Neofidelia sp. 4, Trypoxylon sp.1 4, Megachile sp.1 4, The seven host species removed, collectively comprise over 90% of all host individuals. Hosts were removed stepwise from the dataset, metrics were recalculated, and the models testing for variation in Quantitative Vulneraility and Interaction Evenness, were rerun. Model 1 has haitat type entering the model first, efore parasitoid and host diversity. Model 2 has haitat type entering last, after removal of variation explained y parasitoid and host diversity. Error degrees of freedom decrease as removal of host species leaves no trophic interactions remaining in some plots. No models were significant at an α of

9 Supplementary Figure 2: We analysed the community composition of hosts and parasitoids in each haitat type using the Bray-Curtis similarity index, which incorporates the aundance of each species in each site. A Bray-Curtis distance matrix was constructed using EstimateS (Colwell, R. (1997) EstimateS: Statistical estimation of species richness and shared species from samples, Version 501 availale free at We then used multidimensional scaling to compare differences in community composition across haitats. We found distinct differences in host community composition across haitat types (Suppl. Fig. 2a). Each symol represents the community of a replicate site, and lines represent the outer limit of two-dimensional community space occupied y each haitat type. Pasture and rice showed almost complete overlap in community composition, as did forest and aandoned coffee, however, structure of the pasture/rice community did not overlap at all with that of the aandoned coffee/forest community. Host community composition in coffee showed a large degree of overlap with the aandoned coffee/forest community, and slight overlap with the pasture/rice community, indicating that coffee communities are intermediate etween those of intensively modified and unmanaged haitats. In contrast to the stark separation etween host communities, parasitoid communities showed a high degree of overlap across haitats (Suppl. Fig. 2), with no distinction etween haitats. a) ) 9

10 Supplementary Tale 3: List of host and parasitoid species with identification numer used in quantitative food wes (Fig. 1). Host Species Parasitoid Species 1 Anthidiini Gen. sp. 1 Chalcididae Gen. sp. 2 Anthidium sp. 2 Coelioxys sp. 3 Apidae Gen. sp.1 3 Phygadeuontinae Gen. 4 Apidae Gen. sp.2 4 Melittoia acasta 5 Centris sp. 5 Unidentified parasitoid 6 Eumeninae Gen sp. 6 6 Bomyliid Gen. sp. 7 Euglossa variailis 7 Leucospis sp. 8 Monoia angulosa 8 Chrysis sp. 9 Eumeninae Gen sp. 2 9 Leucospidae Gen. sp.1 10 Eumeninae Gen. sp Eumeninae Gen. sp Apidae Gen. sp.3 13 Megachile sp.1 14 Megachile sp.2 15 Megachilidae Gen. sp.1 16 Megachilidae Gen. sp.2 17 Megachilidae Gen. sp.3 18 Megachilidae Gen. sp.4 19 Megachilidae Gen. sp.5 20 Neofidelia sp. 21 Priochilus nigrocyaneus 22 Pseudodynerus sp. 23 Sceliphrinae Gen. sp. 24 Sphaeropthalminae Gen. 25 Sphecidae Gen. sp.1 26 Sphecidae Gen. sp.2 27 Sphecidae Gen. sp

11 28 Tetrapedia sp. 29 Unidentified host sp.1 30 Trypoxylon sp.1 31 Trypoxylon sp.2 32 Trypoxylon sp.3 33 Zeta sp. 11

12 Supplementary Tale 4: Correlation structure of quantitative food we metrics and variales used in general linear models. Parasitoid richness Host richness Parasitism rate Link density Generality Vulneraility Evenness Connectance Compartment diversity Parasitoid richness Host richness Parasitism rate Link density Generality Vulneraility Evenness Connectance Compartment diversity