Family Strigidae with 22 genera and 121 species known, others suspected; some extinct. Nocturnal, often from obvious reasons. No crop, just a simple enlargement of esophagus. Pellet formation occurs in stomach and egest a pellet for each meal. MPI (meal-to-pellet-interval) directly correlates with quantity eaten. Highest body temperature just before dawn. Rabies has been shed in secretions.