Ernie Janes / Robin (Erithacus rubecula) singing, England, UK, February.

Luiz Claudio Marigo / Canyon of Sao Francisco River near Paulo Afonso town and the CHESF hydroelectric plant and dam, in northeastern Bahia State, northeastern Brazil. December 2009

Jerry Monkman / Comerford Dam and hydroelectric power station on the Connecticut River in Monroe, New Hampshire, USA. April 2007

Oriol Alamany / Gordon hydroelectric dam and reservoir, Southwest National Park, Tasmania, Australia, December

Luiz Claudio Marigo / Aerial view of the hydroelectric dam of Samuel, across the Jamari River, tributary of the right margin of Madeira River, near Porto Velho city, Rondônia State, Western Brazil.

Luiz Claudio Marigo / Aerial view of Samuel hydroelectric dam and lake formed by the dam, west of Porto Velho city, Northern Rondônia State, Western Brazil.

Nick Gordon / Aerial view of Balbina Hydroelectric dam near Manaus, Brazil. It flooded 2400 sq km of rainforest when the dam was opened in 1982.