Bird Mite (or Rodent Mite)
Scientific Name: Ornithonyssus spp. (e.g., Ornithonyssus sylviarum)
Order & Family: Order: Mesostigmata, Family: Macronyssidae
Size: Very small, typically less than 1 mm (approximately 0.7mm to 1mm). They appear as tiny moving specks to the naked eye.
Natural Habitat
Typically found in bird nests (pigeons, starlings, sparrows) or rodent burrows near human dwellings. They migrate into homes through cracks, windows, or vents when their primary host abandons the nest.
Diet & Feeding
Hematophagous (blood-feeding). Their primary food source is the blood of birds or rodents, though they will bite humans if their primary host is unavailable.
Behavior Patterns
They are active parasites that require a blood meal to reproduce. They are negatively phototactic (avoid light) and seek out heat and CO2 sources. They reproduce rapidly, with a life cycle that can be completed in as little as 7 days.
Risks & Benefits
Risks: They bite humans, causing intense itching, skin irritation, and papular dermatitis. While they are nuisance pests, they are not generally known to transmit aggressive diseases to humans. Benefits: None in a domestic setting; they are parasitic.
Identified on: 2/18/2026