Carpenter Ant: These large black ants are especially active in late spring. They are attracted to moist or decaying wood, which is more common after the snow melts and spring rains increase moisture levels. Carpenter ants do not eat wood but tunnel through it to build their nests, which can weaken wooden structures in homes. Their presence is often noticed by the piles of sawdust-like material they leave behind. May is a peak time for their activity as they search for new nesting sites and food sources.

Black Rat: Also known as roof rats, these rodents become more visible in May as they seek food and shelter after winter. Black rats are agile climbers and often nest in attics, walls, or trees. Warmer temperatures and increased outdoor activity can drive them indoors in search of food. They are known for contaminating food supplies and spreading diseases. Their droppings and gnaw marks are common signs of their presence.

Eastern Subterranean Termite: These termites swarm in the spring, especially in May, as they look to establish new colonies. They are attracted to moist soil and wood, which is plentiful after spring rains. Termites feed on cellulose found in wood, paper, and other plant materials, causing significant structural damage over time. Swarmers, or winged termites, are often seen near windows or light sources during this period. Their presence is a sign of an established colony nearby.

Deer Tick: Also called black-legged ticks, these pests are highly active in May due to warmer weather and increased host activity, such as deer and small mammals. They are commonly found in grassy, wooded, or brushy areas. Deer ticks are known for transmitting Lyme disease and other illnesses to humans and pets. Their small size makes them difficult to detect, and they often attach to exposed skin when people or animals brush against vegetation.

Boxelder Bug: These black and red insects emerge in large numbers in late spring. They are often found on the sunny sides of buildings, trees, and plants. Boxelder bugs feed on seeds and leaves of boxelder and maple trees, which are abundant in the region. While they do not cause significant damage, they can become a nuisance when they enter homes in search of warmth or shelter. Their presence is most noticeable on warm, sunny days in May.

Cluster Fly: These flies become active in May as they leave their overwintering sites inside walls and attics. Cluster flies are larger and slower than houseflies and are often found in groups near windows or light sources. They lay eggs in soil, where their larvae parasitize earthworms. Their activity increases with rising temperatures, and they may enter homes in search of food or to escape outdoor conditions.

European Paper Wasp: These wasps begin building their nests in sheltered areas such as eaves, attics, and sheds during May. They are attracted to the increased availability of insects and nectar in spring. European paper wasps are known for their distinctive umbrella-shaped nests and can become aggressive if their nest is disturbed. Their presence is more noticeable as they search for nesting sites and food to support their growing colonies.