What Predators Feed on 13-Year Periodical Cicadas?

Periodical cicadas are one of nature’s most fascinating phenomena, captivating scientists and enthusiasts alike with their synchronized, mass emergences every 13 or 17 years. Among these, the 13-year periodical cicadas, belonging to the genus Magicicada, emerge in large numbers across parts of the United States, creating a unique food bonanza for a wide array of predators. But what animals actually feed on these cicadas? This article delves deep into the world of predators that take advantage of this extraordinary event, exploring how these insects influence ecosystems and predator populations.

Understanding 13-Year Periodical Cicadas

Before diving into their predators, it’s important to understand what makes 13-year periodical cicadas so unique.

Life Cycle and Emergence

Magicicada species remain underground as nymphs for 13 years, feeding on root xylem fluids. After this long developmental phase, they simultaneously emerge in massive numbers. The synchronized emergence is thought to overwhelm predators, a survival strategy known as “predator satiation.” By appearing in such overwhelming quantities at once, cicadas reduce the chance that any one individual will be eaten.

Physical Characteristics

Adult cicadas have distinctive black bodies, orange wings, and red eyes. They are relatively large insects (about 1-2 inches long) and can be quite noisy, with males producing loud mating calls that fill the air during emergence seasons.

The Ecological Impact of Cicada Emergences

The large-scale emergence presents an abundant food resource that temporarily boosts populations of many predators. The event impacts food webs and nutrient cycling within affected ecosystems.

Predators That Feed on 13-Year Periodical Cicadas

A wide variety of animals exploit the periodic cicada bonanza. These include birds, mammals, reptiles, amphibians, insects, and arachnids.

Birds

Birds are among the most significant consumers of cicadas during emergence years.

• Crows and Jays: These intelligent birds are known for opportunistically feeding on cicadas. Crows will often collect cicadas for their young.
• Blue Jays: Blue jays particularly benefit from the periodic abundance and have been observed plucking cicadas from trees mid-flight.
• Grackles and Starlings: These birds gather in flocks to capitalize on the availability of cicadas.
• Woodpeckers: Woodpeckers such as the red-bellied woodpecker consume cicadas by pecking them from tree bark and branches.
• Mockingbirds and Thrushes: Often seen snatching cicadas from leaves or catching them midair.
• Owls: Though not as commonly observed eating cicadas directly, some owl species may prey on other cicada predators or juveniles attracted by the abundance.

Mammals

Various mammals take advantage of this seasonal food source:

• Squirrels: Both gray and fox squirrels gather cicadas to eat or store temporarily.
• Raccoons: Opportunistic feeders like raccoons readily consume cicadas when available.
• Bats: While bats generally hunt flying insects at night, they may catch emerging cicadas during dusk or dawn.
• White-tailed Deer: Occasionally nibble on freshly emerged nymphal exoskeletons or dead adults lying on the ground.
• Opossums: Opportunistic omnivores that include cicadas in their diets during emergences.

Reptiles and Amphibians

Reptiles and amphibians also partake in this feast:

• Lizards: Various lizard species like skinks and anoles actively hunt cicadas on tree trunks and foliage.
• Snakes: Some smaller snakes consume juvenile cicadas or dead adults found on the ground.
• Frogs and Toads: Frequently feed on adult or nymphal cicadas near moist areas.

Insects and Arachnids

Even other arthropods prey upon cicadas:

• Praying Mantises: Known for grabbing large prey items like adult cicadas using their powerful forelegs.
• Spiders: Orb-weaver spiders sometimes catch adult cicadas in their webs.
• Wasps:
• Cicada Killer Wasps (Sphecius speciosus): Paralyze adult cicadas to serve as living food for their larvae. These wasps dig burrows underground where they place incapacitated cicadas for their young to feed upon.
• Other predatory wasps also prey on vulnerable nymphs or adults.
• Ants: Scavenge dead or injured cicadas.

Microbial Predators and Parasites

While not traditional predators, certain microbes and parasites affect periodical cicadas:

• Fungal Pathogens: Entomopathogenic fungi attack weakened or injured individuals during emergence events.
• Parasitoid Flies/Wasps: Some parasitoid species lay eggs inside the nymphs or adults which eventually kill the host insect.

Predator Satiation Strategy vs. Predator Attraction

The sheer number of emerging periodical cicadas means that despite intense predation pressure from multiple species, a majority survive to reproduce. This predator satiation phenomenon works because predators cannot consume all available prey at once, there are simply too many. However, it is important to note that during these outbreaks:

1. Predator populations may increase due to abundant food supply.
2. Some predators rely heavily on periodical cicadas during emergence years but revert to other prey in off-years.
3. The nutrient input from dead or consumed cicada bodies enriches forest soils.

Impacts on Predator Behavior and Population Dynamics

The predictable emergence every 13 years offers a temporary boon allowing certain predator populations to expand:

• Bird species nesting nearby may have higher reproductive success due to increased protein availability.
• Some predatory wasp populations increase because their larvae feed exclusively on captured adult cicadas.
• Mammalian opportunists fatten up before leaner times without such a rich food source.

However, after the event ends and adult cicada availability dramatically decreases until the next emergence cycle, predator populations often decline back toward baseline levels.

Conclusion

The 13-year periodical cicada emergence triggers a remarkable ecological event characterized by predator satiation but also exploitation by numerous animal species across multiple trophic levels. Birds like crows and jays dominate as primary consumers, but mammals including squirrels and raccoons, reptiles like lizards, amphibians such as frogs, predatory insects like mantises and wasps, along with spiders and ants all take part in feeding on these insects. Even microbial pathogens play a role in regulating cicada populations.

This cyclical resource pulse profoundly influences predator behavior, reproduction rates, and population dynamics while contributing nutrients back into forest ecosystems via carcasses left behind. Understanding these predator-prey relationships helps illuminate how ecosystems respond to episodic surges in food availability, and underscores why periodical cicadas remain one of North America’s most extraordinary biological marvels.