Emergent aquatic insects can be valuable subsidies to both aquatic and terrestrial food webs. Fish may influence these subsidies through both lethal and non-lethal effects, including selective predation and chemical cues that increase development rate, resulting in smaller adult body size. For example, baetid mayflies and some predatory stoneflies (e.g., perlids and chloroperlids) have shown smaller adult body size in fish presence. However, the effects of fish on non-predatory stoneflies and various other insect taxa remain unknown. We are assessing if some of these understudied taxa emerge at smaller adult size and biomass in the presence of fish in two small, but diverse, non-perennial streams of the Ozark Highlands (USA), one with fish and the other fishless. In both streams, we ran six in-stream pyramidal emergence traps and six Malaise traps placed within 1 meter of the bank simultaneously during the peak emergence season. Insects were collected into propylene glycol to preserve biomass. We have chosen to evaluate two taxa common in both study streams, an ameletid mayfly, which cannot feed in the adult stage, and a nemourid stonefly, which can. For each individual, we measured either mesonotum width for ameletids or head capsule width for nemourids as proxies for body size. We will also directly measure biomass as ash-free dry mass. Preliminary body size measurements indicate that the ameletid emerged at smaller sizes in the fish stream, reflecting previous findings for swimmer mayflies. Conversely, the nemourid showed no size difference between the fish and fishless streams. This pattern may reflect weak fish predation pressure on nemourids, as their small nymphs primarily occupy interstitial spaces within streambed sediments. Biomass measurements are ongoing, but we anticipate that individuals collected in emergence traps will show similar patterns to body size measurements. We also expect ameletids captured in Malaise traps to exhibit a greater reduction in biomass following emergence than nemourids, whose reduction, we predict, will be minimal. Examining life history responses of previously unassessed emergent aquatic insects due to fish presence is key to understanding top-down influences on secondary production and energy subsidies, particularly in unique, understudied, and underappreciated non-perennial streams.