Bird Mite
Scientific Name: Ornithonyssus sylviarum / Dermanyssus gallinae
Order & Family: Order Mesostigmata, Family Macronyssidae or Dermanyssidae
Size: Extremely small, approximately 0.5 to 1.0 mm (hardly visible to the naked eye until they have fed and turned reddish-brown).
Natural Habitat
Found in wild or domestic bird nests (pigeons, starlings, sparrows, poultry); they often migrate indoors through vents, windows, or cracks when bird hosts leave the nest.
Diet & Feeding
Strictly hematophagous (blood-feeders); they feed on the blood of birds, but will bite humans if their primary bird host is unavailable.
Behavior Patterns
They are semi-permanent parasites that are most active at night. They have a rapid life cycle (about 7 days from egg to adult) and can survive for several weeks without a meal.
Risks & Benefits
Risks: In humans, their bites cause intense itching, red welts, and dermatitis. While they cannot sustain themselves on human blood, they cause significant irritation. Benefits: None; they are considered household and agricultural pests.
Identified on: 2/18/2026