The week in wildlife – in pictures

A Grévy's zebra (Equus grevyi) at Mulhouse zoo, eastern France. Individual zebra can be identified by their markings, which are as unique as a human fingerprint Photograph: Sebastien Bozon/AFP/Getty Images

Two Indian flapshell turtles (Lissemys punctata) engage in a territorial fight in the Keoladeo national park in Bharatpur, India Photograph: Arkaprava Ghosh/Barcroft India

A red squirrel (Sciurus vulgaris) holds a nut in its mouth in a garden in Hanover, Germany Photograph: Julian Stratenschulte/Corbis

A black drongo or royal crow (Dicrurus macrocercus) takes flight to hunt a dragonfly. The avifauna of Bangladesh includes 466 species, 35 of which are globally threatened Photograph: firoz ahmed/Demotix/Corbis

Cosmos flowers in full bloom in Chuncheon, South Korea Photograph: Yonhap/EPA

A golden eagle takes down a sika deer at a nature reserve in Lazovsky district, Russia. The shots were captured by a camera trap set up by Linda Kerley from the Zoological Society of London and her colleagues to monitor Siberian (also known as Amur) tigers in the area. This is the first documented case of such an attack, although golden eagles have a long history of ambitious predatory behaviour Photograph: ZSL/Barcroft Media

A field vole (Microtus agrestis) in an irrigation canal in Almazán, Castilla y León region, Spain. A rainy spring and a dry and hot summer have resulted in a high population of field voles in the region Photograph: Jorge Sanz/Demotix/Corbis

The bright orange landscape of the Namib desert with oryx antelope in the foreground in Soussusvlei, Namibia Photograph: Adalberto Mangini/Barcroft Media

A piece of cassava, a tuber that grows in tropical land, on a plantation in Villa Rica, department of Cauca, Colombia. Colombian researchers have identified up to six groups of bacteria in a cassava processing plant capable of removing cyanide from a river contaminated by gold mining Photograph: Christian Escobar Mora/EPA

Anyone fascinated by the world beneath the waves will love the latest citizen science project from the Zooniverse, the internet's largest, most popular and most successful citizen science site. PlanktonPortal.org takes citizen scientists underwater to explore millions of never-before-seen images of the strange world of plankton Photograph: PlanktonPortal.org

A walrus splashes water Photograph: Christian Charisius/AFP/Getty Images

A tarsier rests on a tree branch in Sulawesi, Indonesia. Each of its eyeballs is approximately 16mm in diameter and is as large as its entire brain, helping it to wait silently in the trees on the lookout for nutritious prey. Although the group was once more widespread, all the species living today are found in the islands of south-east Asia. Photograph: Ronny Adolof Buol/Demotix/Corbis

Flamingos fly over Lake Oloiden in Kenya Photograph: Dai Kurokawa/EPA

Bear cubs inside the forest enclosure of the International Fund for Animal Welfare bear rescue centre, near Bubonitsy, Russia. Russian authorities have made efforts to crack down on hunting which is gaining ground among a wealthy new class Photograph: Alexander Zemlianichenko Jr/AP

Beaver, bison and eagles are among the species that have made a successful comeback in Europe over the past 50 years, according to a major survey published by a coalition of conservation groups Photograph: Stefano Unterthiner/Wild Wonders of Europe

A lime butterfly (Papilio demoleus) sits on a plant in a garden in New Delhi, India. The butterfly population in the Indian capital after rain is increasing and shows greater variety than in the last few years Photograph: Harish Tyagi/EPA

Sparrows raid the bread basket on the terrace of a restaurant in Berlin, Germany Photograph: Kai Pfaffenbach/Reuters

Red deer in the Oostvaardersplassen near Lelystad, the Netherlands. Ecologist Frans Vera wants the 56 square kilometres of nature reserve to be made a Unesco world heritage site Photograph: Robin van Lonkhuijsen/EPA