Sven Zacek,Sven Zacek / Waves along the Baltic Sea coast of Northern Estonia. January 2012.

Staffan Widstrand / Wild Wonders of China / Tiger face in roof tiles. Details from the Taoist Bai Long Wang Miao, White Dragon King Temple, Beiyue Hengshan Mountain, Datong, Hunyuan County, Shanxi Province, China

Staffan Widstrand / Wild Wonders of China / Tiger or owl faces in roof tiles. Details from the Yong An Si temple, now a museum, Beiyue Hengshan Mountain, Datong, Hunyuan County, Shanxi Province, China

Ashley Cooper / Solar tiles on St Silas's church in Pentonville, London, UK. This new solar roof, produces aprox. 47% of the buildings energy needs and will reduce C02 emissions by 7,000 kg per year. October 2010

Ashley Cooper / Solar tiles on St Silas's church in Pentonville, London, UK. This new solar roof, produces aprox. 47% of the buildings energy needs and will reduce C02 emissions by 7,000 kg per year. October 2010

Robin Chittenden / Italian sparrow (Passer italiae) emerging from under roof tile, Sicily, Italy. April.

Nick Upton / Common swift (Apus apus) flying to its nest site under roof tiles on an old cottage, Lacock, Wiltshire, UK, May 2018.

Nick Upton / House sparrow (Passer domesticus) male perched on a roof gutter near its nest entrance under old tiles, with a faecal sac it has just brought from the nest, Wiltshire, UK, June.

Nick Upton / House sparrow (Passer domesticus) female perched on a cottage roof gutter near the entrance to its nest under old tiles, Wiltshire, UK, June.

Nick Upton / House sparrow (Passer domesticus) male flying to its nest site under old roof tiles on a cottage carrying nest material in its beak, Wiltshire, UK, June.

Nick Upton / House sparrow (Passer domesticus) female hopping up from a roof gutter to its nest entrance under old tiles with insect prey for its chicks, Wiltshire, UK, June.

Nick Upton / Common swift (Apus apus) flying from its nest site under roof tiles on an old cottage, Hilperton, Wiltshire, UK, July.