Blood gas partial pressures, pH, and bicarbonate and lactate concentrations were measured from the basilic vein of mourning doves (Zenaida macroura) and the jugular vein of boat-tailed grackles (Quiscalus major) and house sparrows (Passer domesticus) to assess immediate impacts of mist net capture and handling for banding and venipuncture. Mourning doves and house sparrows exhibited mild acidemia (median [minimum–maximum] venous blood pH_41°C = 7.394 [7.230–7.496] and 7.395 [7.248–7.458], respectively), relative to boat-tailed grackles (Quiscalus major; 7.452 [7.364–7.512]), but for different reasons. Mourning doves exhibited relative metabolic acidosis (lower venous blood pH, higher lactate concentrations, lower bicarbonate, and no significant differences in partial pressure of CO₂ (pCO₂) or partial pressure of O₂ (pO₂) compared with boat-tailed grackles). House sparrows exhibited relative respiratory acidosis (lower venous blood pH, higher pCO₂, lower pO₂, and no significant differences in bicarbonate and lactate concentrations compared with boat-tailed grackles). All birds captured by mist net and handled for banding and venipuncture experienced some degree of lactic acidemia; and values were greater in mourning doves (lactate, 7.72 [3.94–14.14] mmol/L) than in boat-tailed grackles (5.74 [3.09–8.75] mmol/L) and house sparrows (4.77 [2.66–12.03] mmol/L), despite mourning doves resisting least and being easiest to disentangle from the mist net. House sparrows were more susceptible to respiratory acidosis, warranting particular care in handling birds <30 g to minimize interference with ventilation. The different sample collection site for mourning doves may have affected results in comparison with the other two species, due to activity of the wing muscles. However, despite the higher lactate concentrations, pCO₂ was relatively low in doves. The metabolic, respiratory, and acid–base alterations observed in this study were minor in most cases, indicative of the general safety of these important field ornithology techniques. The effect of other adverse conditions, however, could be additive.