We studied food webs comprising fish, macroinvertebrates, and algae (identi
fied to species or morphospecies) in small streams using a consistent metho
dology at the same spatial and temporal scales. Our aim was to test apriori
hypotheses derived from dynamic-demographic and energetics models concerni
ng the effects of disturbance and resource availability on food-web attribu
tes. The regime of bed disturbance affecting the organisms in the webs was
measured in 10 streams. We also derived measures of the supply of resources
for animals in the webs in terms of algal primary productivity and detritu
s standing crop. Both web size and number of links per species were signifi
cantly negatively related to mean intensity of bed disturbance. Mean chain
length had a significant positive relationship with algal primary productiv
ity but not disturbance, No food-web attribute was related to detritus stan
ding crop.