The temperature-dependent development of pupae and adults of strawberry root weevil (SRW) Otiorhynchus ovatus (L.) was studied in strawberry (Fragaria x ananassa Duch. var. 'Totem'). The development of pupae and adults was investigated at constant temperatures from 3-33��C at 3��C intervals. Major emphasis was on the development of a weighted linear temperature-based pupal prediction model. The predictive ability of this weighted model was compared to a traditional non-weighted linear degree-day model by relating predictions to the observed occurrence of SRW lifestages determined by field sampling. The upper thermal lethal limit for SRW pupae was between 30 and 33��C. Pupae did not eclose below 6��C. Mean pupal duration was 127 d at 6��C and 7 d at 30��C. Rate of development (1/days) was greatest at 30��C. The weighted linear pupal prediction model produced a developmental threshold of 4.3��C and a degree-day requirement of 227.3. The non-weighted linear pupal prediction model produced a developmental threshold of 6.2��C and a degree-day requirement of 163.9. Adults fed at all temperatures from 3-33��C and oviposited at temperatures between 18 and 30��C . The longest preoviposition period (32.8 d) and the least total number of eggs (2.2) were observed at 18��C. The shortest preoviposition period (15.1 d) and the greatest total number of eggs (282.5) were observed at 27��C. A temperature range of 21 to 27��C appeared to be optimum for oviposition; i.e. relative to other temperatures, preoviposition time was short, mortality was low, and total number of eggs laid was high. / Graduation date: 2000