A wavelength and pulsewidth-tunable actively modelocked fibre ring laser employing a 151cm-long bismuth-oxide-based highly nonlinear erbium-doped fibre (Bi-HNL-EDF) and a bandwidth-variable tunable filter is demonstrated. An 80nm continuous wavelength tuning from 1535 to 1615nm can be achieved by utilising the wide gain bandwidth of the Bi-HNL-EDF. The pulsewidth can also be tuned from 7.8 to 23.1ps by changing the filter bandwidth. High nonlinearity of the Bi-HNL-EDF collaborates with spectral filtering by the filter to suppress the supermode noise quite effectively. The total cavity length is as short as 14m. Thus, clean pulses with a repetition rate of 10GHz are successfully obtained over the entire tuning ranges. Back-to-back bit error rate tests also confirm bit error free modelocking operation.