Why a plastic bag on rear-view mirrors stops territorial birds in France

In France, this tip spotted on some vehicles is intended to prevent a surprising clash between territorial birds and their reflections.

Published on 6 June 2025, the report cited by the original outlet, whose name is not specified in the extract provided, describes a straightforward solution: covering exterior rear-view mirrors when a bird repeatedly attacks a parked car.

A reflection mistaken for a rival

A plastic bag tied around a rear-view mirror may seem amusing at first glance. However, it addresses a very real issue, commonly seen in spring and early summer. During this period, several bird species actively protect their territory, nesting area or mate.

The issue arises when the bird sees its image in the mirror’s reflective surface. It does not necessarily identify the image as its own reflection. Instead, it may perceive another bird occupying its territory and posing a threat.

The rear-view mirror itself is not the target: it is the reflection it produces that triggers the bird’s response.

The League for the Protection of Birds explains that territorial behaviour can become more intense during the breeding season. Some males then try to drive away any individual they regard as a competitor. When faced with a car mirror, they may repeatedly peck, beat their wings and scratch at it.

This can continue for several hours and may happen again over successive days. The bird returns to the same location, finds what it believes is its rival and resumes the attack. Vehicles parked near hedges, gardens, trees, agricultural areas or buildings containing nests may be especially affected.

Damage that can be more noticeable than expected

The first marks usually appear on the rear-view mirror housing and glass. Claws and beaks can leave scratches on the plastic. With repeated impacts, the mirror may also shift or become loose.

Droppings are another nuisance. They are not merely unsightly: they may contain uric acid, which can damage the paintwork if left on the bodywork for a long time, particularly in hot weather or direct sunshine.

The level of risk depends on how long the droppings remain on the vehicle, the condition of the paint and the weather. Gentle, prompt cleaning helps prevent staining. Conversely, rubbing dry droppings with a rough cloth can cause micro-scratches.

• Scratches may develop on the rear-view mirror’s plastic housing and glass.
• Repeated impacts can weaken the mirror mechanism.
• Droppings left on the bodywork may stain the paint finish.
• The bird may return every day for as long as it can see its reflection.

Covering the rear-view mirror to break the cycle

The suggested solution is to completely conceal the rear-view mirror surface with a plastic bag. The aim is not to frighten the bird away. Rather, it removes the trigger: its image in the mirror.

Once the reflection is gone, so is the supposed competitor. The bird therefore has less reason to perch in the same place and strike the glass. A shopping bag or small plastic bag may be enough, provided it fully covers the mirror and remains secured in windy conditions.

This temporary protection works by removing the reflection visible to the bird, rather than attempting to drive it away.

An elastic band or a knot can secure the bag around the housing. The cover must be removed before driving. A covered rear-view mirror severely reduces the driver’s side visibility and must never remain in place while the vehicle is moving.

A temporary measure that is safe for the bird

A plastic bag is a short-term response. It can be fitted when the car is parked for several hours or overnight, then removed before any journey. This approach avoids using repellent products whose effectiveness or impact on wildlife is not always known.

It is also important not to try to catch the bird, move a nest or destroy eggs. In France, many wild bird species, along with their nests and eggs, are protected. If a nest creates a difficulty, it is better to seek advice from a suitable association or the relevant authorities before taking any action.

What applies in France

In France, exterior rear-view mirrors must allow the driver to monitor the sides and rear of their vehicle. Covering them is only useful when the car is stationary. Before setting off, the driver must remove the bags and check that the mirrors are correctly adjusted.

Wildlife protection also calls for a careful approach. A bird attacking its reflection is not trying to attack people or the car itself. It is responding to a visual stimulus as part of territorial behaviour. Concealing the reflective surface can therefore lessen the problem without unnecessarily disturbing the animal.

Useful steps around the vehicle

When the attacks keep occurring, the driver can identify when they take place and check whether another reflective element is also attracting the bird: a side window, shiny wheel trim, highly polished bodywork or a window near the parking space.

Parking in a slightly different spot can sometimes be enough to break the bird’s routine. Both rear-view mirrors can also be protected temporarily, even if only one appears to be targeted, to prevent the bird shifting its attention to the other side of the vehicle.

Finally, the plastic bag should not become discarded litter. Once removed, it can be reused or disposed of through the appropriate waste stream. The tip is inexpensive, but it only makes sense if it protects both the car and its immediate environment.