What Are Crazy Ants?

Crazy ants are ants known for their quick erratic movements. These ants dash around and move in seemingly random patterns. They’re unlike other ants that follow trails and generally walk in straight lines.

There are different species of crazy ants including the following:

• Anoplolepis gracilipes
• Paratrechina longicornis
• Nylanderia fulva

In this article, we’ll learn more about crazy ants as we look deeper into these species.

Anoplolepis gracilipes (Yellow Crazy Ant)

Anoplolepis gracilipes is commonly known as the yellow crazy ant. They have long slender bodies that measure around 4-5 mm (0.15-0.19 in).  They have long legs and antennae, making them one of the largest invasive ant species in the world. [1]

They get their name from their erratic movements and yellowish-brown color.

Habitat

Yellow crazy ants are believed to be native to West Africa or Asia. However, they have since become well-represented in many tropical regions worldwide.

They prefer to live in moist and shaded habitats. These include forests, urban areas, and agricultural lands. They nest in soil, under rocks, logs, and electrical appliances.

Diet

Yellow crazy ants have a broad diet including plant and animal material. They are opportunistic eaters that exploit a wide range of food sources.

They, for example, tend to sap-sucking insects, like scale and aphids for honeydew. They also feed on nectar, fruits, grains, and seeds.

Additionally, yellow crazy ants prey on many invertebrates. These include other insects, arachnids, earthworms, and even land crabs.

Colony Structure

Yellow crazy ants have polygynous colonies. This means that they have more than one reproductive queen. In fact, they can create large supercolonies with more than 1000 queens. 

These supercolonies can have millions upon millions of workers.

Reproduction

Yellow crazy ants reproduce sexually and disperse through budding. In this process, they don’t fly out to swarm but mate close to their nests. The mated queens then take some workers and break away to start new colonies.

See this article to learn more about how ants reproduce.

Threats

Yellow crazy ants are one of the top 100 worst invasive species. Their large colonies and aggressive behavior drive and wipe out native populations.

They, for example, have a significant impact on the biodiversity of Christmas Island. Their large colonies have essentially wiped out the native crab populations. They have killed millions of red and land crabs on the island.

It’s not only crabs as well. Populations of ground and canopy-dwelling animals have also decreased. They also encourage the growth of scale insects that negatively affect plant growth. In fact, the scale insects that they tend to have already killed mature trees.

Paratrechina longicornis (Longhorn Crazy Ant)

The Paratrechina longicornis is otherwise known as the Longhorn crazy ant. They’re relatively small ants that measure around 2.3-3 mm (0.09-0.11 in) long. They’re usually brown to black in color and have grayish hairs on their bodies. [2]

They get their name from their erratic movements and extremely long antennae.

Habitat

Similar to yellow crazy ants, longhorn crazy ants are believed to have come from Asia or Africa. Likewise, they have since spread to most of the world’s subtropical and tropical areas.

Longhorn crazy ants are highly adaptable. They can live in both dry and moist habitats. They, for example, are common pests in houses and can live in urban areas. They nest in trash, wood, soil, and building debris. They’re also found in other environments like beaches and farms.

Diet

Longhorn crazy ants are also omnivores. They feed on insects, lizards, seeds, fruits, and household food. Like yellow crazy ants, they too tend to scale bugs that produce honeydew.

See this article to learn more about what ants eat.

Colony Structure

Longhorn crazy ants are polygynous. A single nest can contain up to 40 queens and 2000 workers. They can also form large supercolonies that contain millions of ants.

Reproduction

Longhorn crazy ants also reproduce sexually and disperse through budding.

Threats

Longhorn crazy ants are also considered an invasive species in many parts of the world. They displace native animals and damage crops. They also infest homes and buildings.

Studies also show that Longhorn crazy ants can transport pathogenic microbes in hospitals.

Nylanderia fulva (Rasberry Crazy Ant)

The species Nylanderia fulva are sometimes called the Rasberry crazy ant. They get this name from Tom Rasberry, who noticed their increasing numbers in 2002. They’re also called tawny crazy ants for their reddish-brown color. [3]

Rasberry crazy ants are small. Their workers measure around 2.0-2.3 mm (0.08 -0.09 in) in length. Meanwhile, their drones are slightly larger at 2.4-2.7 mm (0.094-0.1 in), and queens are ~4.0 mm (0.15 in) or longer.

Habitat

Raspberry crazy ants are native to South America but are now present in the neotropics. They can live in different habitats including grasslands and urban areas. 

They nest under or within any object or void. They’re found in stumps, soil, concrete, rocks, and anywhere with moisture. They typically nest outdoors but will invade homes and other structures to forage.

See this article to learn more about where ants live.

Diet

Rasberry crazy ants are also omnivorous. They eat both plant and animal matter. 

These ants especially like to eat honeydew from scale insects. Like other crazy ants, they tend to these insects and provide them protection. 

They are also attracted to sweets like nectar and fruit. They get their protein from other insects and small arthropods.

Colony Structure

Rasberry crazy ants are polygynous and can form large colonies. In South America, Rasberry crazy ants from different colonies are mutually intolerant. 

However, those in North America show signs of supercolony behavior. There, workers of different colonies show no signs of aggression. They consider each other as relatives.

Reproduction

Similar to other polygynous colonies, Raspberry crazy ants mate close to their nests. They then establish new colonies through budding.

Threats

Like the other crazy ants, Raspberry crazy ants are invasive pests. They’re highly aggressive and pose different types of threats including the following:

• Ecological Damage: Rasberry ants drive out other ant species and animals in an area. They attack both small and large animals and can sometimes cause fatalities. They also cause crop damage due to their relationships with scale insects. 

• Electrical equipment: Rasberry crazy ants can sometimes accumulate in electrical equipment. This can cause short circuits and equipment failure. They, for example, have caused damage to airbag sensors in automobiles.

Are Crazy Ants Dangerous?

Yes, crazy ants are dangerous. They create large colonies and are highly invasive. While they’re generally harmless, they can cause significant ecological, agricultural, and structural damage.

Due to their populations, they’re also extremely hard to control. Baits and insecticides often don’t work as well as they do with other ants. Hence they require a lot of resources to manage.

Summary: What are Crazy Ants?

To summarize, crazy ants are ants known for their erratic behavior. They make quick random movements that make them look crazy and have no sense of direction. They include different species including Anoplolepis gracilipes, Paratrechina longicornis and, Nylanderia fulva.

These species are highly invasive. They’re considered pests and can do significant ecological damage. They form large supercolonies and drive out native species. This leads to a chain reaction that often changes the entire landscape of an environment.