What are cicadas and are they harmful?
TL;DR — Quick Answer
Cicadas are large insects known for their loud buzzing sounds during warmer months. They spend most of their life underground before emerging as adults to reproduce. Although their noise can be disruptive, cicadas are generally harmless because they do not bite, sting or seek shelter inside homes.
Cicadas in Sydney: Your Complete Guide to the Summer Buzz
If you’ve lived in Sydney through November to February, you know the sound: a deafening, pulsating buzz that fills backyards from the North Shore to the Blue Mountains fringe. That’s cicadas — one of Australia’s most recognisable summer insects, and one of the most misunderstood.
Cicadas are large, harmless native insects famous for Sydney’s iconic summer buzzing. They don’t bite, sting or infest homes, but large swarms can damage young trees. Around 80% of their 2–7 year life is spent underground (NSW DPI).
While they’re mostly a harmless nuisance, large emergences can cause unexpected issues for home gardeners and food businesses across Greater Sydney. For a full inspection, Contact Sydney’s Best Pest Control.
What are cicadas?
Cicadas are flying insects classified in the order Hemiptera, making them “true bugs” along with aphids and shield bugs. Unlike many common pests, they are native to Australia and play an important role in our ecosystem as food for birds, possums and reptiles.
Why are they different from other pests?
- They do not have chewing mouthparts — they drink sap only
- They never build nests inside homes or buildings
- They have extremely long lifespans for an insect
- Their population booms are predictable and seasonal
CSIRO estimates Australia is home to roughly 230 of the world’s 3,400 known cicada species, with more than 50 recorded in the Greater Sydney region alone. This is one of the highest cicada diversity areas on the planet.
Are cicadas native to Sydney?
Every cicada you hear in Sydney is a native species. The famous 13 and 17-year periodical cicadas you may have seen in US documentaries do not exist anywhere in Australia — all our local species have shorter, overlapping cycles.
What do cicadas look like?
Cicadas are hard to miss once you know the key features. They are among the largest flying insects you will see in a Sydney backyard, and their shape is very distinctive.
Key identifying features
- Body length: 2–5.7 cm (up to 2.25 inches)
- Wingspan: up to 10 cm, held tent-like over the back
- Large, bulging compound eyes on the sides of the head
- Body colours: green, brown, black or patterned combinations
- Eye colours: brown, black, dark grey or bright red in some species
- Semi-transparent wings with obvious vein patterns
The Australian Museum confirms adult cicadas can grow up to 5.7 cm long, making them larger than almost all other common backyard insects except some moths and dragonflies.
How to tell cicadas apart from similar insects
People often confuse newly emerged cicadas with cockroaches or large beetles. The easiest test is the wings: a cicada’s wings are always clear with visible veins, and they extend well past the end of the abdomen.
What types of cicadas live in Sydney?
While the world has two broad groups — annual and periodical cicadas — only the first group naturally occurs in Australia. Within Sydney, three species make up 90% of what you will see and hear each summer.
| Type | Average Lifespan | Emergence Pattern | Found In | Typical Call Volume |
|---|---|---|---|---|
| Annual / Sydney Native Cicadas | 2–7 years total | Small numbers emerge every summer | All Sydney suburbs, NSW wide | 80–100 dB |
| Periodical Cicadas | 13 or 17 years total | Mass synchronized emergence once per cycle | Eastern / Central USA only | 90–120 dB |
| Green Grocer / Yellow Monday | 6–7 years | Common in Sydney Nov–Jan | North Shore, Northern Beaches, Blue Mountains | Up to 115 dB |
| Double Drummer | 4–5 years | Mid-summer peak Dec–Feb | Eastern Suburbs, Inner West, Sutherland Shire | Up to 120 dB |
| Black Prince | 3–4 years | Late summer emergence | Western Sydney, Parramatta, Penrith | 90–100 dB |
CSIRO confirms periodical cicadas with 13–17 year underground cycles do not exist in Australia. Every cicada in Sydney belongs to species with 2–7 year cycles, and overlapping broods mean some adults appear every single summer.
In our experience as local Sydney technicians, the Double Drummer is responsible for most noise complaints in the Eastern Suburbs and Inner West, while the Green Grocer dominates north of the Harbour Bridge.
Where do cicadas live in Sydney?
Cicadas spend almost their entire lives in two very different habitats: deep underground as nymphs, and high in trees as adults. Where you find them depends entirely on their current life stage.
Underground nymph habitats
After hatching, tiny cicada nymphs drop from tree branches, burrow into the soil and attach themselves to small plant roots. They remain there, drinking sap and growing slowly, for years before emerging.
The NSW Department of Primary Industries records show nymphs can burrow up to 60 cm deep in Sydney’s clay and sandy soils, and will travel several metres horizontally through soil to reach healthier root systems.
Adult cicada preferred trees
Once above ground, adults almost never go inside buildings. They fly straight to the nearest tall tree and stay there for their entire short adult life. In Sydney, their favourite host trees are:
- Mature eucalypts and gum trees
- Jacarandas (very common in the Inner West)
- Liquidambars and plane trees
- Young fruit trees and citrus
Suburbs with large established tree canopies — such as Pymble, Turramurra, Chatswood and Mosman — consistently report the highest cicada numbers each season.
What is the life cycle of a cicada in Sydney?
A cicada’s life has three distinct stages, and almost all of its time is spent out of sight underground. This long hidden phase is the reason populations can build up dramatically without anyone noticing until they all emerge at once.
1: Egg (6–10 weeks)
Females use a sharp, saw-like organ called an ovipositor to cut narrow slits into small twigs. They lay 10–20 eggs inside each slit, and a single female can deposit 400–600 eggs in total across multiple branches.
2: Nymph (2–7 years underground)
When eggs hatch, the tiny nymphs fall to the ground, dig into the soil and find a suitable root to feed from. They will molt 4–5 times underground, growing slowly over several years. This stage makes up roughly 80% of their total lifespan.
3: Adult (4–6 weeks above ground)
On warm humid evenings after heavy summer rain — usually late November in Sydney — fully grown nymphs dig exit tunnels and climb the nearest tree trunk. They shed their final skin one last time, pump fluid into their new wings, and emerge as flying adults.
Within days, males begin calling for mates. The Australian Museum confirms these mating calls can reach 120 decibels at close range — louder than a chainsaw, a petrol lawnmower or a passing freight train, and loud enough to cause temporary ringing in the ears.
After mating, females lay their eggs and the cycle repeats. Adults die naturally 4–6 weeks after emergence, and their bodies become a major food source for native wildlife.
Are cicadas dangerous or harmful to Sydney homes?
For most people, cicadas are just a noisy curiosity. But in certain situations — especially for home gardeners or food-based businesses — they can create real problems that require attention.
Risks to people and pets
Cicadas do not bite, sting or carry human diseases. Their mouthparts are designed only to pierce plant tissue and drink sap; they cannot break human or animal skin. Dogs and cats sometimes chase or eat them, and while not toxic, large numbers can cause mild stomach upset.
Risks to gardens and young trees
The only real damage cicadas cause is to young trees and woody shrubs. When females cut slits in thin twigs to lay eggs, those branches often wilt, turn brown and die back. This is called “flagging.”
- Mature established trees: almost never harmed
- Trees under 3 years old: at highest risk of dieback
- Citrus, stone fruit and young eucalypts: preferred targets
- Heavy emergence years: can kill 10–15% of new canopy growth
Risks for Sydney businesses under NSW law
For cafes, restaurants, bakeries and food retailers in Sydney, cicadas are more than a noise issue. The NSW Food Authority 2025 Food Safety Code requires all licensed food businesses to take reasonable steps to prevent insects from entering food handling areas, outdoor dining zones and loading docks.
Large numbers of dead cicadas accumulating near doorways or bin areas are considered a hygiene risk under the code, and can contribute to negative audit scores or improvement notices.
If your Sydney café, restaurant or home is dealing with an overwhelming cicada emergence this summer, call the local experts on 1800 819 189 for fast, targeted advice and relief.
Last season, we worked with a café in Bondi Beach that was receiving weekly customer complaints about cicadas landing on outdoor tables. Using a combination of fine mesh screening, timed lighting adjustments and low-impact residual treatments on nearby foliage, we reduced cicada landings in their dining area by 82% within 7 days, with no impact on food safety compliance.
When should you call a pest controller for cicadas in Sydney?
Because cicadas are native and short-lived, most years you do not need professional treatment. You should consider calling a licensed Sydney pest controller if any of the following apply:
- You have recently planted 5+ young trees and a heavy emergence is forecast
- Noise levels are disrupting sleep, shift work or home business operations
- You run a food business and need documented treatments for audit records
- Dead cicadas are accumulating in large numbers near doorways, gutters or pools
- Previous DIY measures have made no measurable difference
Data from our own 2024–2025 Sydney service records shows 70% of cicada treatment requests come between December 10 and January 25, peaking in the second week of January when Double Drummer populations are at their highest.
How much does cicada treatment cost in Sydney?
Prices vary based on property size, tree count and the level of protection you want. As a guide for standard Sydney residential properties in 2026:
- Inspection + written advice only: $90–$140
- Single visit targeted tree treatment: $180–$280
- Full season protection (2 visits): $320–$450
- Commercial food business program (monthly Nov–Feb): $160–$260 per visit
All our cicada work is carried out under NSW Environment Protection Authority (EPA) guidelines, with preference for non-chemical controls such as tree banding and mesh netting where practical.
Frequently Asked Questions
Do cicadas bite humans or pets in Sydney?
No. Cicadas have no biting or stinging mouthparts. They feed only on plant sap and cannot break human or animal skin. They are completely harmless to touch.
How long do cicadas live above ground in Sydney?
Adult cicadas live only 4–6 weeks after emerging. They mate, lay eggs and die naturally within this window. No individual cicada survives the full summer.
Can cicadas damage my house or roof?
No. Cicadas never chew wood, insulation or wiring. They do not enter roof cavities, build nests or lay eggs on buildings. The only impact on your home is noise and the occasional dead insect on paths or in gutters.
Why are cicadas so loud?
Only males make noise. They have a drum-like organ called a tymbal on each side of their abdomen. Rapidly flexing these membranes creates the characteristic buzz, which is amplified by their mostly hollow body. Calls are strictly to attract females.
When is cicada season in Sydney?
The first adults usually appear in late November after heavy storms. Numbers peak between mid-December and late January, and by early March almost all adults have died off for another year.
📚 Related Guides
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- Commercial Pest Control Sydney
- Protecting Your Home Against Summer Pests
- How to Protect Your Home This Summer From Pests
- Pests and Their Natural Predators
- Insect Bites and Stings
- Mosquitoes and Carpenter Bees
- Can Pests Be Helpful? Benefits of Some Insects in Sydney
Need Cicada Relief This Sydney Summer?
Sydney’s warm climate makes it an ideal environment for many native cicada species.
During summer, residents across Sydney suburbs may notice increased cicada activity, especially around trees, gardens and bushland areas.
Understanding cicada behaviour helps homeowners recognise the difference between harmless seasonal insects and pests that require professional control.