Evenings on the balcony are over, and so are the bites. It is tempting to think the tiger mosquito problem is settled until next summer. In reality, part of next season is being prepared right now, in saucers, watering cans and buckets left outside.
The tiger mosquito (Aedes albopictus) is now established in the Île-de-France region. The adults die off or disappear with the cold, but in autumn the females laid eggs that can survive the winter dry, stuck just above the waterline. With the first mild spring rains, they hatch.
Here is how to spot these egg-laying sites at home, then on a café, restaurant or hotel terrace, and what autumn cleaning really changes.
Where the tiger mosquito lays its eggs on a balcony
The tiger mosquito does not lay in ponds or lakes. It picks small amounts of clear water in containers, often in the shade. A bottle cap is enough. On a balcony or terrace, the usual sites are:
- saucers under flowerpots, by far the most common;
- watering cans, buckets and basins left outdoors;
- stacked empty pots and planters without a drainage hole;
- children's toys, folded tarpaulins and garden furniture covers that form pockets of water;
- terrace floor drains and channels, blocked gutters;
- poorly covered rainwater butts.
In summer, the cycle from egg to adult can take only about a week. That is why the official advice during the season is to empty standing water at least once a week.
The big autumn clean, item by item
In autumn, emptying the water is no longer enough: the eggs stay stuck to the sides, dry. You need to scrub them off or store the item under cover. This table sums up the useful steps.
| Item | Action | Why |
|---|---|---|
| Saucers | Empty, scrub the inner wall with a brush, or fill them with sand | The eggs are stuck to the rim, above the water |
| Buckets, watering cans, basins | Empty, brush, store upside down or indoors | An upturned container no longer collects water |
| Empty pots and planters | Stack under cover, check drainage holes | Pot bottoms hold water for weeks |
| Tarpaulins and covers | Pull taut or store, avoid folds | A pocket of water on a tarpaulin is enough for egg-laying |
| Drains, channels, gutters | Clear leaves, run water to check it drains | Debris holds standing water |
| Rainwater butt | Fit a lid or a fine, taut mosquito net | Keeps females out in spring |
The brush matters more than any product: a simple scrub with soapy water dislodges the eggs. There is no point using insecticide on a balcony in winter.
Why your neighbours matter as much as you do
The tiger mosquito does not fly far: it generally stays within around 150 metres of where it emerged. If you get bitten on your balcony in summer, the breeding site is therefore very probably at your place or at a close neighbour's.
That makes it an ideal subject for collective action. In a co-owned building, the syndic (managing agent) can have the roof terraces, inner courtyards, drain covers and gullies and rainwater downpipes checked, as they are beyond the reach of individual residents. A notice in the entrance hall at the end of the season, listing the steps in the table above, also helps.
Café, restaurant and hotel terraces
For a business, this directly affects customer comfort. A planted terrace, a hotel patio or an office roof terrace multiply breeding sites: planters, shrub tubs, decorative fountains, hollow parasol bases, self-watering reservoirs.
A few good habits to build into your routine:
- a weekly round during the season, from May to the end of November, with a list of water points to empty;
- an end-of-season clean of planters and tubs, following the table above;
- a check of terrace gullies and drains after each spell of rain;
- for self-watering tubs, regular maintenance or a mosquito net cover.
When to call in a professional
Removing breeding sites remains the core of mosquito control, and it mostly depends on you. A technician is useful when water points are numerous, hard to reach or impossible to empty (roof terrace, inspection chamber, pond). We then follow the Sentinel Protocol:
- Inspect: survey of breeding sites and permanent water points, backed by photos.
- Treat: during the season, a targeted, approved larvicide treatment of water points that cannot be removed.
- Sanitise: removal or protection of containers, layout advice to avoid standing water.
- Follow up: a follow-up visit as set out in the protocol, a photo report, and active vigilance on your side during the period of enhanced surveillance, from 1 May to 30 November.
If you think you have seen a tiger mosquito in a French municipality where it has not yet been recorded, you can report it on the official reporting portal.
Going further
Our insect treatment service covers mosquitoes, in your home as well as in your premises, in Paris and across the Île-de-France region. Sourced figures on the spread of the tiger mosquito in France are gathered on our pest statistics page. For an apartment building, see our page for managing agents; for a business, our annual contracts. Prices are published on the pricing page and you can book a slot online.
FAQ
Do tiger mosquito eggs really survive the winter?
Yes. In autumn, females lay eggs that can enter a resting phase and withstand cold and dryness for months. Stuck to the sides of containers, they hatch when water covers them again in spring. That is why containers need scrubbing, not just emptying.
Should I treat my balcony with insecticide in winter?
No. In winter there are no active adults left and an insecticide does nothing on a balcony. The effective step is mechanical: empty, brush and store containers under cover, clear the channels and cover water reserves. Targeted professional treatments are for the active season.
Can the tiger mosquito transmit diseases in the Île-de-France region?
It can transmit the dengue, chikungunya and Zika viruses if it first bites an infected person. That is the reason for the enhanced surveillance organised every year from 1 May to 30 November. If you develop a fever after a stay in an area where these viruses circulate, see a doctor.
To see this topic in the light of public data (ANSES, Santé publique France, MNHN), read our sourced pest statistics.
