Bird Mite or Rodent Mite
Scientific Name: Ornithonyssus spp. (e.g., O. bursa, O. sylviarum)
Order & Family: Mesostigmata: Macronyssidae
Size: Very small, approximately 0.7 to 1 mm long (barely visible to the naked eye as a moving speck).
Natural Habitat
Typically found in bird nests (pigeons, starlings, sparrows) or rodent burrows near human dwellings; often migrate indoors when their primary host leaves the nest.
Diet & Feeding
haematophagous (blood-feeding); they primarily feed on the blood of birds or rodents but will bite humans if the primary host is absent.
Behavior Patterns
These mites are nocturnal or active in low light. They move quickly for their size. When a nest is abandoned (e.g., fledglings leave), the mites migrate in search of a new food source, often entering homes through cracks, vents, or windows.
Risks & Benefits
Risks: They are a significant nuisance pest. Their bites cause intense itching, irritation, and rashes (dermatitis) in humans, though they technically cannot survive and reproduce on human blood alone. They do not generally transmit diseases to humans but are highly annoying. Benefits: None in a domestic setting.
Identified on: 2/9/2026