Image caption Rock star Brian May was among anti-badger cull protesters in central London

Whitehall chiefs are monitoring social media messages in an attempt to head-off demonstrations against policies such as the badger cull.

The Department for Rural Affairs uses "horizon scanning" software to gain an "early warning" of public protests.

Other government departments are being encouraged to follow Defra's lead.

The tactic was revealed in the government's communication plan for 2013/14, which also announced a 16% cut in spending on advertising and PR.

The government has set aside £237m for communication in 2013/14, down from £285m in 2012/13, although more cash could be allocated to individual campaigns that "develop during the year in response to new policy priorities".

The report encourages government departments to make more use of social media, such as Twitter and Facebook, to promote their policies, as a cheaper and more effective alternative to TV and print advertising.

'Public panic'

The Department for Education is praised for producing podcasts, films and quizzes to promote the new national curriculum for England to teachers, who were sent links to the content during the "golden hours of 6-8pm on weekdays and 1-4pm on Sundays when teachers are most active on social media".

Defra is indentified as a "centre of excellence" for its use of horizon scanning software - something that is increasingly common in the private sector, as consumer brands attempt to head off social media backlashes against their products.

"It (Defra) uses social analytics to act as an early warning of emerging issues (anti-badger culling demonstrations, public farmer protests) that affect the department by reporting on social network discussions and hot topics in real time so that the communications team can respond quickly," says the report.

Defra's "incident response team" also uses the software, which is developed with commercial partner Gorkana, to "ensure that the right information (floods, horsemeat, disease outbreaks) is delivered to targeted audiences quickly and effectively".

"The need to prevent public panic during incidents and emergencies (food shortages, flood evacuations) is high on Defra's agenda, and so their social media monitoring has been crafted to meet exacting standards," says the report.

'Wargaming'

Social media is widely used by people campaigning against government policies to drum up support for petitions and organise demonstrations.

Image caption Animal rights campaigners rely on the internet to get their message out

Anyone with a computer can check what animal rights campaigners are saying about the badger cull on Twitter under the hashtags #stopthecull and #badgercull.

But the Defra software is likely to capture a far wider range of sources, including blogs and messages on services like Facebook and LinkedIn, enabling civil servants to work out a way of combating their arguments and spot sudden upsurges in sentiment that might provide early warning of an outbreak of direct action.

Thousands of people, including celebrities Brian May and Bill Oddie, descended on central London earlier this month to protest against the badger cull, in an event that was widely publicised and planned with police.

But with the cull cleared to begin in two test areas, in Gloucestershire and Somerset, police are reportedly concerned about "surprise" attempts by protesters to disrupt the shooting of the animals, which takes place at night.

According to The Guardian, police are "wargaming" demonstrations with the culling company and even some protest groups, who plan to use strobe lights and make loud noises with vuvuzelas to disrupt the killing.

Earlier this month, Defra won an award from the International Association for the Measurement and Evaluation of Communication for "best use communication management: public sector".

The civil servant in charge of the programme, Elayne Phillips, said in a blog that delegates at the award ceremony had been "surprised at the vast range and volume of sources that inform Horizon Scanning, the filtration process that involves cross government co-ordination including No 10 and the easy digest dashboards that we produce to present the intel simply".

brian.wheeler@bbc.co.uk