'Feed the ducks bread' sign sparks heated online debate

Experts and commenters disagree on whether it helps or harms ducks and swans

A sign urging people to feed "starving" ducks with bread has gone viral and sparked a heated debate about whether it is in the animals' best interests.

A neatly designed sign appeared in a park in Buxton, Derbyshire, but the managers of the park denied any responsibility.