Do Ants Eat Spiders?

Yes, ants do eat spiders. Most ants are omnivores, meaning their diet consists of both plant and animal matter. As such, they eat a variety of food including other invertebrates like spiders.

In fact, some studies have shown certain ants to be among the primary predators of some spiders. For example, weaver ants are common predators and known to be particularly dangerous to jumping spiders.

Do All Ants Eat Spiders?

Not all ants eat spiders. Some ants are herbivorous and only eat plant matter such as nectar, pollen, fungi, vertebrate waste, and plant wound secretions.

Which Ants Eat Spiders?

Most, if not all omnivorous ants eat spiders. They commonly eat spiders when they’re dead and don’t put up any resistance but some ants are also known to attack and prey on them. These ants are as follows:

Weaver Ants

Weaver ants are arboreal (living in trees) ants known primarily for their unique nest building behavior of constructing nests by weaving leaves together with larval silk. They’re also highly territorial ants that aggressively defend and prey on spiders, insects, and other invertebrates, that harm their host tree.

As mentioned, they’re known to be particularly dangerous for jumping spiders and are in fact, considered to be one of the primary predators of such spiders in tropical regions.

Fire Ants

Among the common spider predators are the ever notorious fire ants. These are invasive and highly aggressive predatory ants known for their painful stings which inject paralyzing venom.

Due to their aggressive predatory behavior, fire ants usually suppress the population of other invertebrates. In fact, research has shown a negative relationship between fire ant populations and the abundance of spider species in an affected area.

Bigheaded Ants

Bigheaded ants are dimorphic ants from the genus Pheidole which get their name from the disproportionately large heads of their soldiers. These soldiers have large mandibles that they rely on to dissect and tear their prey apart.

Similar to fire ants, bigheaded ants are aggressive ants known to prey on spiders. Likewise, research has also shown the same negative correlation between their populations and the abundance of spiders. 

Crazy Ants

Crazy ants are another group of invasive ants that prey on spiders. These relatively smaller ants with reddish color and tiny hairs on their bodies, are known for their erratic movement and large colony populations which drive out other organisms.

Crazy ants spray their prey with blinding or agitating formic acid which then allows them to swarm and attack.

Argentine Ants

Argentine ants are highly aggressive ants with an appetite for spiders. These ants form large colonies with fully cooperative workers that can kill and displace other invertebrates.

As such, they are often considered to be a threat to biodiversity and like the aforementioned ants, have been shown to cause a decrease of spiders in an affected area.

Why Do Ants Eat Spiders?

Ants eat spiders because they’re generally available for predation. Ants and spiders usually require the same living conditions and therefore live in the same habitats. This increases the likelihood that they encounter each other and provides predatory ants plenty of chances to attack.

Spiders are also simply a good food source for ants. They provide nutrients including carbohydrates, fats, folic acid, zinc, and a generous amount of protein, which ants all use to properly function and survive.

• Carbohydrates: Ants use carbohydrates to produce glucose for respiration, a biochemical process which allows cells to obtain energy. In short, spiders provide ants with energy which they use to fuel their bodily processes.

• Fats: Like carbohydrates, fats help fuel the cellular processes in an ant’s body. They may also be broken down into fatty acids which serve as building blocks for cuticular waxes and the synthesis of certain pheromones and defensive compounds.

• Folic Acid: Folic acid can be converted to folates which are cofactors in a number of different bodily reactions. They’re essential for normal growth and development.

• Zinc: Zinc is a mineral which enhances and hardens certain parts of the ant body. For example, studies have found that zinc makes up 8% of the weight of ant teeth and is uniformly arranged and distributed to enhance tooth hardness, maintain sharpness, and maximize cutting efficiency. 

• Protein: Spiders provide a good amount of protein which ants can break down to build or replace enzymes, hormones, and other proteins needed for growth and development.

How Do Ants Eat Spiders?

As mentioned, ants may eat spiders dead or prey on them to eat them alive.

• Detritivory: As detritivores, ants have no qualms with foraging for and eating dead spiders. In fact, most if not all omnivorous ants will happily take back dead spiders to their nests for consumption.

• Predation: Again, there are also some ants that will actively attack spiders and kill them for eating. These ants usually prey on a spider by swarming it and grabbing different parts of its body to pin it. From there, they use their stingers to paralyze the spider or simply go straight into using their mandibles to tear its appendages apart into smaller pieces that can easily be carried back to the colony nest.

Related Questions

Do Spiders Eat Ants?

Yes, spiders do eat ants. Lynx spiders and black widows for example, are known specifically to prey on ants. Also, while some ants are known to be among the primary predators of salticidae, some of these jumping spiders actually also feed on ants.

Can Ants And Spiders Live Together?

Despite the fact that different types of ants and spiders may eat each other, some of them can actually live together. Certain spiders called myrmecomorphs and myrmecophiles are social parasites that develop mutualistic to parasitic relationships with ants.

These spiders mimic ants and integrate themselves with ant colonies to primarily gain protection against their predators and to partake in the colony’s food stores. For example, spiders of the species Gamasomorpha maschwitzi live around or inside the bivouacs of the army ant, Leptogenys distinguenda, where they feed on insects captured by their hosts.

Summary: Do Ants Eat Spiders?

Yes, ants do eat spiders. Most ants are both omnivores and detritivores and as such, eat spiders whether they are dead or alive. Some spiders such as weaver ants, fire ants, and bigheaded ants, are also known to prey on spiders and have been in fact shown to negatively affect spider abundance in an affected area.

It also doesn’t help that spiders are nutritious and generally available for ants to prey on. As ants and spiders typically share the same living conditions, they often live in the same habitat and therefore increase the chance of predation and detritivory.