Anteaters are fascinating animals that feed primarily on ants and termites. Their long snouts and sticky tongues are perfectly adapted for seeking out and consuming these insects. But just how many ants does an anteater eat in a given year? Let’s take a closer look at anteaters and their voracious appetites to find out.
The Anteater’s Diet
Anteaters are part of the order Pilosa, which includes sloths and armadillos. There are four living species of anteaters: the giant anteater, the silky anteater, the northern tamandua, and the southern tamandua. All species feed predominantly on ants and termites, which make up about 90% of their diet. The other 10% consists of other insects and small invertebrates.
Anteaters are highly specialized to find and consume ants and termites. Their tubular snouts allow them to poke into nests and mounds. They have no teeth, but use their long, sticky tongues to lap up the insects. Their tongues can protrude more than 2 feet! Anteaters swallow their prey whole and rely on their muscular stomachs to grind the insects up.
Estimating An Anteater’s Consumption
An anteaters daily food intake depends on its size and species. The giant anteater is the largest, consuming up to 30,000 insects per day. Silky anteaters are the smallest and eat around 2,000 insects daily. Tamanduas are of medium size and eat around 9,000 insects per day.
To estimate how many ants an anteater eats per year, we need to know:
- The number of insects it eats per day
- The percentage of its diet that is ants/termites
- The number of days in a year (365)
Let’s calculate for a giant anteater:
- 30,000 insects per day
- 90% are ants and termites = 27,000
- 27,000 ants x 365 days = 9,855,000 ants per year!
For a tamandua:
- 9,000 insects per day
- 90% are ants and termites = 8,100
- 8,100 ants x 365 days = 2,956,500 ants per year
Factors That Influence Consumption
There are a few factors that cause the number of ants an anteater eats per year to vary:
- Species – As we saw, giant anteaters eat way more than tamanduas or silky anteaters.
- Size – Larger individuals within a species will eat more than smaller ones.
- Season and climate – In warm months when ants are active, anteaters eat more. In colder months with less ant activity, they eat less.
- Reproductive status – Pregnant and lactating females have higher caloric needs.
- Abundance of prey – When ant and termite numbers are high, anteaters can eat more.
These factors can cause anteaters in the same habitat to consume anywhere from 50% to 150% of the estimated yearly averages. In good conditions with lots of prey, anteaters can eat substantially more than our baseline estimates.
Ant Availability
An important consideration is whether anteaters deplete their local ant and termite populations. Research suggests anteaters do not cause long-term reductions in prey density. Ant and termite colonies are resilient to predation. Their populations can rapidly recover and maintain high densities with anteaters present.
There are somewhere between 10,000-100,000 ants in a typical mound. Tropical habitats where anteaters live have incredibly high densities of ants and termites. The Amazon rainforest has been estimated to contain over 400 billion insects per acre. About 10-15% are ants and termites, so trillions are available as prey.
With anteaters occupying large home ranges up to 80 square km, they continuously move between many nests and colonies. This prevents them from over-exploiting any single area. Their voracious ant consumption is sustainable thanks to the super-abundance of prey.
Comparison To Other Ant Predators
To fully appreciate how many ants anteaters eat, let’s compare them to some other major ant predators:
| Animal | # of Ants Eaten Per Day |
|---|---|
| Antlion Larva | 10-50 |
| Aardvark | 50,000 |
| Pangolin | 70,000 |
| Silky Anteater | 2,000 |
| Giant Anteater | 30,000 |
This puts the anteater’s shocking consumption into perspective. An aardvark and pangolin are the only other animals that rival anteaters for the title of “World’s Greatest Ant Predator.” Antlions and other small insectivores consume a relatively tiny number of ants daily.
Impact on Ant Populations
Researchers have looked at how anteaters affect ant and termite populations:
- Ant diversity does not decline in the presence of anteaters. All species are able to persist.
- The overall density and biomass of ants is not negatively impacted by anteaters.
- Anteaters may suppress particularly aggressive or competitive ant species through targeted predation.
- This can potentially enhance ant diversity by preventing the dominance of a few species.
So while anteaters gorge on astronomical numbers of ants, they do not drive down ant populations overall or cause local extinctions of colonies. Ant and termite densities remain high enough to support stable anteater populations.
Ant Behavioral Defenses Against Predation
Ants have evolved interesting behaviors to defend themselves against anteater predation:
- Chemical alarms – Ants release pheromones to alert the colony, stimulating fleeing or aggression.
- Hiding and evacuation – Ants immediately flee deep into the nest at the first sign of an anteater.
- Biting and stinging – Soldier ants swarm and attack anteaters to drive them away.
- Rocking – Entire ant nests shake and move to make themselves harder anteaters to access.
These adaptations allow ants to survive alongside anteaters. They likely prevent anteaters from depleting any given nest or colony before moving on.
Unique Adaptations for Myrmecophagy
Anteaters have their own suite of adaptations to be able to consume ants in such bulk:
- Narrow, tubular snout to poke into ant mounds
- Extremely sticky saliva to entrap ants
- Elongated tongue covered with sticky saliva
- No teeth, swallowing food whole
- Powerful claw for ripping into ant nests
- Thick hide and hair for protection from ant bites
These traits allow anteaters to ransack ant colonies and consume thousands of ants per day. They can crack into nests, sweep up mouthfuls of insects with their tongue, and swallow them whole rapidly.
Anteaters and Ants – An Ancient Arms Race
The evolution of anteaters driven by myrmecophagy (ant and termite eating) exemplifies an arms race between predator and prey.
Ants evolved chemical defenses, mass attack, and nest behaviors to protect against predators. In response, anteaters developed morphological and behavioral counter-adaptations to overcome these defenses and exploit ants as a food source.
This likely drove an evolutionary back-and-forth over millions of years. Ants strengthened their defenses, so anteaters evolved physiological tools to overcome them. Neither side has been able to completely neutralize the other, resulting in a stable predator-prey balance.
Conclusion
Anteaters consume astronomical amounts of ants – up to 150 million per year for the largest giants. Yet this predation does not drive ant populations extinct or even reduce their density and biomass. The superabundance of ants, resilience of their colonies, and adaptations of both predators and prey lead to a sustainable balance.
The voracious appetite of the anteater and the endless hordes of ants that sustain it are a remarkable example of predator-prey dynamics. Their arms race has produced some of the animal kingdom’s most astonishing adaptations for both consumption and defense of tiny prey.
