A reveler strikes a pose during an unofficial carnival block party referred to as “blocos”, in Rio de Janeiro, Brazil, Saturday, February 26, 2022. City Hall banned all blocos, the tightly packed street parties attended by those who cannot or don't want to buy pricey tickets for the official parade at the Sambadrome, due to a wave of the Omicron variant. (Photo by Silvia Izquierdo/AP Photo)

Kalep, 5, in a bear costume, participates in parade where his father Johnny Lopez was the Elder Angel, during the Oruro Carnival, a traditional celebration that can be traced back to the indigenous Ito festival, in Oruro, Bolivia February 26, 2022. (Photo by Wara Vargas/Reuters)

Members of the Unidos da Tijuca samba school parade at the “Opening of Carnival 2022” event, at the Cidade do Samba, in Rio de Janeiro, Brazil, 27 February 2022. The event is a preview of the parades of the Samba Schools of the Special Group, postponed to April due to the COVID-19 pandemic in Brazil. (Photo by Andre CoelhoEPA/EFE)

Alex Sun, left, Peter Simplicio and Matt Connelly jump through a hole in the ice into Lake Andrews on the Bates College campus, Friday, February 9, 2024, in Lewiston, Maine. The annual Bates College Puddle jump started 50 years ago as a Winter Carnival tradition. (Photo by Andree Kehn/AP Photo)

Members of Imperio Serrano samba school get ready prior to their entrance during 2023 Carnival parades at Marquês de Sapucaí Sambodrome on February 19, 2023 in Rio de Janeiro, Brazil. (Photo by Buda Mendes/Getty Images)

A Waura Indian woman watches the activities of this year's “quarup”, a ritual held over several days to honour in death a person of great importance to them, in Xingu National Park, Mato Grosso State, August 24, 2013. This year the Waura tribe is honouring their late cacique (chief) Atamai, who died in 2012 and helped created the Xingu Park, and his important contribution in facilitating communication between white Brazilians and Indians. (Photo by Ueslei Marcelino/Reuters)

A woman shouts asking for help during an eviction in Rio de Janeiro, Brazil, Friday, April 11, 2014. Squatters in Rio de Janeiro are clashing with police after a Brazilian court ordered that 5,000 people be evicted from abandoned buildings of a telecommunications company. Officers have used tear gas and stun grenades to try to disperse the families. (Photo by Silvia Izquierdo/AP Photo)

Global wildlife populations will decline by 67% by 2020 unless urgent action is taken to reduce human impact on species and ecosystems, warns the biennial Living Planet Index report from WWF (World Wide Fund for Nature) and ZSL (Zoological Society of London). From elephants to eels, here are some of the wildlife populations most affected by human activity. Here: The maned wolf is among the large mammals in the Brazilian Cerrado that are threatened by the increasing conversion of grasslands into farmland for grazing and growing crops. (Photo by Ben Cranke/Nature Picture Library/Alamy Stock Photo)