Bird Mite (also known as Rodent Mite or Nest Mite)
Scientific Name: Ornithonyssus spp. (e.g., Ornithonyssus sylviarum or Ornithonyssus bursa)
Order & Family: Order: Mesostigmata, Family: Macronyssidae
Size: Very small, approximately 0.7 to 1 mm in length (barely visible to the naked eye/speck of dust size).
Natural Habitat
Primarily found in bird nests (pigeons, starlings, sparrows, poultry) or rodent burrows. When their primary host leaves or dies, they migrate into homes through cracks, windows, or vents in search of a meal.
Diet & Feeding
Hematophagous (blood-feeding). They primarily feed on the blood of birds or rodents but will bite humans and pets if their preferred hosts are absent.
Behavior Patterns
They are nocturnal and reproduce rapidly. They rely on the warmth, moisture, and CO2 of hosts to locate them. They cannot fly or jump but crawl quickly. Without a blood meal, they typically die within a few weeks.
Risks & Benefits
Risks: Their bites cause intense itching, skin irritation, rashes, and a sensation of crawling on the skin. While they are nuisance pests and cause dermatitis, they are not generally known to transmit diseases to humans. Benefits: None in a domestic setting; they are parasitic.
Identified on: 2/28/2026