The animal, imported from North America in the late 19th century to populate large estates, has gradually taken precedence over its English cousin and threatens many species of trees.

As part of a government plan, scientists are planning to give gray squirrels an oral contraceptive in their diet. The project, tested in the north of England and in Wales, proved to be rather conclusive.

Thus about 70% of gray squirrels ate in small boxes placed in their natural habitat and designed in such a way that other animals would not have access to them. Now the idea is to put a contraption in addition to the food in these boxes.

For Gideon Henderson, scientific adviser to the Ministry of the Environment, this contraceptive device, less invasive and more effective than beaten or poisoned campaigns, is promising.

“This will help the red squirrels (…) return to their natural habitat while protecting UK forests and increasing biodiversity”He assured.

“Without effective management, red squirrels could disappear from parts of the UK”Vanessa Fawcett of the association The Red Squirrel Survival Trust explains.

At present, no contraceptive has been used in the trials, but according to scientists it will be effective in both men and women.

The population of gray squirrels in the UK is estimated to be 2.7 million, a number that continues to grow. In contrast, there are only 140,000 red squirrels in the country, most of which are in Scotland.

More vulnerable, redheads also require more space per capita and are at risk from squirrel pox brought on by Grey, who are immune.

Gray squirrels also endanger the health and survival of young trees, as they shed bark, weakening them and causing them to die.