Identification and Life Cycle
Ladybugs are insects and are members of the beetle order, Coccinellidae. Other frequently used names are ladybirds or ladybird beetles. There are over 500 species in the United States, and over 4,500 worldwide.
They are small oval shaped insects approximately 1/4 – inch long with six legs. Its head is round with a chewing mouthpart, eyes and antennae. They have a hard shell (elytra), that protects the body and its wings. They are usually bright orange, yellow or red with black spots. Sometimes the ladybug can be a solid color; yellow, brown or black, with no pattern at all.
They have 4 life cycle stages; egg, larva, pupa, and adult. The adult ladybug females lay eggs, usually on leaves or grasses. Depending on the species, she may lay from just a few eggs to 1,000 eggs. The eggs hatch into larvae in about 1 to 2 weeks. They feed for 1 to 2 weeks, molting as they grow, build a cocoon, or pupa, which they they then emerge as adults. It will look soft and pink or very pale for a few hours until its shell becomes hard. As it hardens, it also gains pigment and then the ladybug becomes its characteristic bright red color. They can live up to a year.
Habits and Damage
Most ladybugs eat aphids (up to 60 per day), but also eat a variety of other plant harmful insects and insect eggs. Farmers favor the ladybug because they rid their crops of pests such as scale insects and spider mites. Ladybugs can be eaten by stink bugs, spiders and toads, and more uncommonly by birds. They are not harmful to people or destructive to homes. They do not eat fabric, plants or other household items.
During the winter months, they will seek out a warm place to hibernate and huddling together in a large group. They nest in dense vegetation, under logs and tree bark, sometimes indoors in cracks in old buildings, in door frames, folds in curtains, and sheds.
Ladybugs are attracted to light colored homes, usually older homes, and once they make their way inside, they can be hard to get rid of. They can enter wall spaces in in the fall, and remain unseen until the spring when they come out to search for food. Some may become active on warm days during the winter or early spring, and find their way into living spaces inside your home. When in large numbers, they can quickly become an indoor pest by crawling over the walls, windows, light fixtures, etc.
They release pheromones, which is similar to a scent to attract other ladybugs. They use this to communicate during mating and hibernation, and are detected by other ladybugs up to 1/4 mile away. This chemical “scent” can linger for years not only outside a structure, but also inside.
The ladybug’s color is it defense mechanism. An insect’s bright colors displayed in nature often indicate that it is poisonous or bad tasting. Its bright colors serve as a warning, and produces a foul-smelling liquid to warn off a predator. This liquid is a small amount of its blood released when stressed.
Prevention and Management
The best strategy for ladybug control is prevention. An Integrated Pest Management (IPM) program can properly identify the pest and help you maintain a ladybug-free environment inside and out.
It is important to recognize and alter conditions around a home or building to limit areas where ladybugs can gain access from the outside and hibernate indoors where they can then become a household nuisance in fall and winter. Limit the areas where insects can gain access into buildings, especially around doors & windows.
The following steps can be taken to help prevent or reduce a potential problem with ladybugs.
- Make roosting & nesting areas unavailable to them. Block areas such as openings to lofts, steeples, vents, and eaves.
- Discourage people from feeding pigeons in public areas, and near commercial buildings.
- Eliminate pools of standing water.
- Attach wood or metal sheathing at a 45-60 degree angle over window ledges & other flat surfaces to keep pigeons from landing.
- Install “bird wires” to keep pigeons off ledges, railings, awnings and rooftops.
- Use netting to keep pigeons out of large areas.
- Pigeons can be controlled by capturing them in traps placed near their roosting or feeding sites.