I understand the whole wanting to be humane but mice carry lost of diseases which is not only harmful to you but also your quails . I honestly would put my compassion for the mice aside and focus on the safety of your birds and self .. uses the snap traps ,dispose of bodies in trash, wash hand and bleach everything the lil shits have come into contact with . Stay safe .
Hantavirus
Mouse feces and urine can dry and turn to dust, spreading viruses through the air we breathe. Hantavirus is commonly spread this way and can cause fever, chills, and aches and pains. If left untreated, it can progress to kidney failure and intense shortness of breath.
Salmonella
Mice may track waste debris, along with dirt and bacteria, across countertops. This is a common cause of salmonella (food poisoning), as we may touch kitchen surfaces while making food. Symptoms like fever, stomach pain, vomiting, and diarrhea can become serious over time.
Lymphocytic Choriomeningitis (LCMV)
This viral infection is typically carried by house mice and can cause serious neurological problems. Humans become infected through exposure to fresh mouse droppings, urine, saliva, and nesting materials.