Bird Mite (or Rodent Mite)
Scientific Name: Ornithonyssus spp. (e.g., Ornithonyssus sylviarum or Ornithonyssus bursa) or Liponyssoides sanguineus
Order & Family: Order: Mesostigmata; Family: Macronyssidae
Size: Very small, approximately 0.7 to 1 mm in length; barely visible to the naked eye as a moving speck.
Natural Habitat
Typically found in bird nests (pigeons, starlings, sparrows, poultry) or rodent nests. They migrate into homes when their original host leaves or dies, often entering through windows, vents, or cracks near nests.
Diet & Feeding
Hematophagous (blood-feeding). They primarily feed on the blood of birds or rodents but will bite humans and pets if their primary host is unavailable.
Behavior Patterns
They are active parasites that require blood meals to survive and reproduce. They are nocturnal or crepuscular but can be active during the day. They cannot complete their life cycle on human blood but will bite persistently in search of a suitable meal.
Risks & Benefits
Risks: Their bites cause intense itching, red welts, and skin irritation (dermatitis) in humans. While generally not known to transmit diseases to humans (unlike ticks), the psychological stress and irritation of an infestation are significant. Benefits: None in a domestic context; they play a role in regulating populations of their host species in nature.
Identified on: 3/7/2026