Latest News from BPCA

28 January 2021

Defra backs birth control for grey squirrels

Department for Environment, Food and Rural Affairs (Defra) has backed a proposal by UK Squirrel Accord (UKSA) to use oral contraceptives in grey squirrel control. 


The method involves luring grey squirrels into feeding boxes only they can access, with little pots containing hazelnut spread spiked with an oral contraceptive.

Environment minister Lord Goldsmith says the damage they and other invasive species do to the UK's woodlands costs the UK economy £1.8 billion a year.

On Tuesday, Defra told BBC News: "We hope advances in science can safely help our nature to thrive, including through the humane control of invasive species."

Grey squirrels (Sciurus carolinensis) are invasive pests, not native to the UK.

They were first introduced to the UK from North America in the 1870’s, as ornamental additions to high-class estates and country homes.

Introductions continued until the 1930’s, when the damage they can cause was finally acknowledged and it became illegal to release grey squirrels into the wild.

There are three reasons we control grey squirrels:

  • Their potential to damage to your home, business and health
  • The destruction of UK forests
  • The impact on our native wildlife, in particular the red squirrel.

Under the spotlight

UKSA has been experimenting with ways to deliver oral contraceptives to squirrels for more than three years now.

Last year, it tested special feeding stations designed so only grey squirrels can gain access in woodland in East Yorkshire.

UKSA thinks this could be a more effective, less labour intensive, non-lethal method for managing grey squirrels.

Instead of contraceptives, the hazelnut paste bait was dosed with Rhodamine B as a marker which, when ingested, causes squirrel hair to fluoresce under UV light.

The researchers found that more than 90% of the grey squirrel population being studied visited the traps.

They concluded that it was possible to deliver repeat doses of a contraceptive to the majority of grey squirrels in a wood.

UKSA thinks this could be a more effective, less labour intensive, non-lethal method for managing grey squirrels.


For more information on grey squirrels and their control, visit our website.

Source: Online