Twenty-eight nests, each from a different group, were watched for a total of 232 h (8·29 ± 0·77 h). Sufficient data were available from 58 adults. A single prey item was delivered on each of the 1792 recorded visits to the nest. Nine categories of prey were identified: spiders (Araneae), centipedes (Chilopoda), cockroaches (Blattodea), mantids (Mantidae), termites (Isoptera), bugs (Hemiptera), caterpillars (Lepidoptera), fruit and ‘other invertebrates’, which encompassed prey types not readily identifiable in the other groups. A manova, using the seven most common prey types (which made up 94·2% of the selection), showed no significant effect of dominance class on the proportion of prey types brought to the nest (F7,47 = 0·61, P = 0·748). However, both year (F14,47 = 2·37, P = 0·007) and sex (F7,47 = 9·06, P < 0·001) had a significant influence on prey delivered. Separate anova revealed that males delivered significantly more caterpillars (F1,53 = 15·98, P < 0·001; Fig. 2), centipedes (F1,53 = 26·00, P < 0·001) and cockroaches (F1,53 = 21·86, P < 0·001) and significantly fewer termites (F1,53 = 10·93, P = 0·004) and ‘other invertebrates’ (F1,53 = 14·21, P < 0·001) than females. The proportion of ‘other invertebrates’ (F2,53 = 3·97, P = 0·032) and spiders (F2,53 = 3·79, P = 0·041) varied significantly between years.
Males delivered significantly heavier prey than females (males = 0·47 ± 0·03 g, females = 0·27 ± 0·05 g; t = 3·51, d.f. = 56, P < 0·001). There was no significant difference in the biomass of prey delivered by dominant and subordinate males (t = 0·56, d.f. = 32, P = 0·580) or females (t = 0·40, d.f. = 22, P = 0·690). Caterpillars, centipedes and cockroaches were significantly heavier than other prey items delivered (anova: F6,1631 = 106·26, P < 0·001).