A bird is cleaned at the International Bird Rescue in Fairfield, California January 20, 2015. A gooey, unknown material discovered on the eastern shores of San Francisco Bay is clinging to the feathers of birds, and more than 100 birds, mostly species of oceangoing, diving ducks, have died after their feathers were fouled by the viscous substance now undergoing testing at state labs in Sacramento. (Photo by Robert Galbraith/Reuters)

Brendan Fitzpatrick is a commercial photographer specialising in advertising and lifestyle photography. He also creates unique X-ray images marketed under the banner Invisible Light. Brendan is based in Sydney, Australia. (Photo by Brendan Fitzpatrick)

Most pet cats will become timid or defensive when outdoors, but not Millie – after being adopted by her mountain-climbing owner Craig Armstrong, Millie has become a feline hiking and mountain-climbing legend.

The Grand National springs to mind as the yearly highlight of the “sport of kings” – thoroughbred steeds and their brave jockeys triumphing (or failing) over gruelling courses and high-fenced adversity. And now steeplechase enthusiasts can add another event to the annuls of great sporting occasions, namely the Stuttgart rabbit show jumping. Here: Rabbit showjumping at an animal fair in Stuttgart, Germany, on November 16, 2014. (Photo by Action Press/Rex Features)

In this handout image provided by Taronga Zoo, an unnamed baby Goodfellows Tree Kangaroo joey is seen in it's mothers pouch on March 10, 2014 in Sydney, Australia. Taronga Zoo is celebrating the successful birth of its first Goodfellows Tree Kangaroo joey in more than 20 years. Zookeepers have only just begun seeing her peeking out from first-time mother, Qwikilas, pouch after she was born in September last year. (Photo by Taronga Zoo via Getty Images)

A three month old white Bengal female tiger cub looks around her enclosure at the Buenos Aires Zoo, Argentina, Wednesday, April 16, 2014. Cleo, a captive Bengal white tiger at the zoo, gave birth to two females and one male white tiger cubs on January 16, 2014. (Photo by Natacha Pisarenko/AP Photo)

An old woman looks from inside a car with bullet holes and shattered windows as she flees fighting in the eastern Ukrainian town of Slaviansk June 9, 2014. REUTERS/Gleb Garanich.

Three Boeing 737 fuselages lie on an embankment on the Clark Fork River after a BNSF Railway Co train derailed Thursday near Rivulet, Montana in this picture taken July 4, 2014. A train derailment in Montana this week damaged a shipment of jetliner fuselages and other large parts on its way to Boeing Co factories in Washington state from Spirit Aerosystems, Boeing said on Saturday. (Photo by Kyle Massick/Reuters)