A swallow bug is a species of parasitic insect belonging to the family Cimicidae, which also includes the common bed bug. These small, flattened, reddish-brown insects are obligate hematophagous ectoparasites, meaning they feed exclusively on the blood of warm-blooded animals. Unlike their more generalized relatives, these specific parasites exhibit a strong preference for avian hosts, primarily infesting the nests and roosting sites of swallows and martins. Their lifecycle is intimately tied to the breeding cycles of their avian hosts, with populations flourishing when nests are active.
what is a swallow bug
Swallow bugs, scientifically known as Oeciacus vicarius, are tiny insects, typically measuring between 3 to 5 millimeters in length when fully grown. Their bodies are oval-shaped and remarkably flat, an adaptation that allows them to hide effectively within narrow crevices of bird nests. The color of these insects can vary from a translucent reddish-brown after a recent blood meal to a darker, opaque brown when unfed. Distinguishing features include their segmented antennae and vestigial wings, which render them incapable of flight.