Fig. 5. Mechanical power (Pmech) for wind tunnel flight by two starlings carrying a respirometry mask, with Pmech estimated by two aerodynamic models (bird 15, vortex ring model 
; bird 15, lifting line model 
; bird 19, lifting line model 
).
Fig. 5. Mechanical power (Pmech) for wind tunnel flight by two starlings carrying a respirometry mask, with Pmech estimated by two aerodynamic models (bird 15, vortex ring model ; bird 15, lifting line model ; bird 19, lifting line model ).