MOST people know the meaning of St Valentine's Day in its modern concept - ie yet another campaign by the retail industry to sell more goods - but few realise that the actual day, February 14, is a key date in the wildlife calendar.
Ancient observers noted that it was half way through February that birds began their mating ceremonies and started to look round for nesting sites - a symbol for burgeoning love which later became attached to human behaviour.
Now St Valentine's Day notes the start of National Next Box Week, when people are urged to provide new homes for many of our smaller birds species, including the once ubiquitous house sparrow.
For reasons yet unknown, sparrows have gone into a vicious spiral of decline in recent years, their numbers decimated in some areas. So this week, staff at the Yorkshire Dales National Park Authority put up nesting boxes for eight sparrow couples at their Grassington HQ (see picture).
One strange twist: the nesting boxes, in sets of four, are made by prisoners at Durham Jail so this is a case of jailbirds giving a helping hand to their free feathered friends.