Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) 
is an invasive polyphagous agricultural and urban nuisance pest of Asian origin 
that is becoming widespread in North America and Europe. Despite the economic 
importance of pentatomid pests worldwide, their feeding behavior is poorly 
understood. Electronically monitored insect feeding (EMIF) technology is a 
useful tool in studies of feeding behavior of Hemiptera. Here we examined H. 
halys feeding behavior using an EMIF system designed for high throughput studies 
in environmental chambers. Our objectives were to quantify feeding activity by 
monitoring proboscis contacts with green beans, including labial dabbing and 
stylet penetration of the beans, which we collectively define as 'probes'. We 
examined frequency and duration of 'probes' in field-collected H. halys over 48 
hours and we determined how environmental conditions could affect diel and 
seasonal periodicity of 'probing' activity. We found differences in 'probing' 
activity between months when the assays were conducted. These differences in 
activity may have reflected different environmental conditions, and they also 
coincide with what is known about the phenology of H. halys. While a substantial 
number of 'probes' occurred during scotophase, including some of the longest 
mean 'probe' durations, activity was either lower or similar to 'probing' 
activity levels during photophase on average. We found that temperature had a 
significant impact on H. halys 'probing' behavior and may influence periodicity 
of activity. Our data suggest that the minimal temperature at which 'probing' of 
H. halys occurs is between 3.5 and 6.1 °C (95% CI), and that 'probing' does not 
occur at temperatures above 26.5 to 29.6 °C (95% CI). We estimated that the 
optimal temperature for 'probing' is between 16 and 17 °C.