Bird mite / Rodent mite
Scientific Name: Ornithonyssus sylviarum / Liponyssus sanguineus
Order & Family: Order: Mesostigmata, Family: Macronyssidae
Size: Exceedingly small, typically 0.5 to 1.0 mm; often appearing as a tiny moving speck to the naked eye.
Natural Habitat
Typically found in bird nests (under eaves, in chimneys) or rodent nests. They may enter homes when their hosts (birds or mice) leave or die.
Diet & Feeding
They are hematophagous, meaning they feed on the blood of their animal hosts (birds or rodents).
Behavior Patterns
They are highly mobile and nocturnal. While they prefer animal hosts, they will crawl onto humans and bite if their primary host is unavailable. They cannot complete their life cycle on human blood alone.
Risks & Benefits
Risk: Their bites cause intense itching, red welts, and skin irritation in humans. They do not typically transmit diseases to humans but can cause significant discomfort. Benefit: None to humans; they are considered household and agricultural pests.
Identified on: 3/26/2026