Indian Runner ducks march past farm buildings at the Vergenoegd wine estate near Cape Town, South Africa, May 16, 2016. Each day, a quack squad of killer ducks are released for the first of two sorties at South Africa's Vergenoegd wine farm in Stellenbosch. Their mission – seek and destroy thousands of pests out to ruin the season's harvest. Fanning out across the vineyards, some 1,000 Indian Runner ducks hone in on their hidden targets with uncanny precision, locating the tiny white dune snails feasting on budding vines. (Photo by Mike Hutchings/Reuters)

A rare white kiwi chick is seen only days after being hatched on May 22, 2011 in Wellington, New Zealand. The all-white kiwi, named “Manukura” is suspected to be the first white chick born in captivity. The chick is the thirteenth of fourteen baby kiwis hatched at the wildlife centre this season. (Photo by Mike Heydon/Jet Productions NZ Limited via Getty Images)

Singer-songwriter Sheryl Crow meets Clyde the Sea Lion, the star of SeaWorld San Diego's “Sea Lion Tonite”, at the marine-life park's Sea Lion and Otter Stadium on August 3, 2011 in San Diego, California. Crow and her sons spent the day a SeaWorld meeting, feeding and learning about sea turtles, penguins and sea lions, other park animal ambassadors. Crow was performing in San Diego on her summer concert tour with Kid Rock. (Photo by Mike Aguilera/SeaWorld San Diego via Getty Images)

General view of the screens in Hyde Park to showing the Royal Wedding on April 29, 2011 in London, England. The marriage of Prince William, the second in line to the British throne, to Catherine Middleton is being held in London today. The Archbishop of Canterbury conducted the service which was attended by 1900 guests, including foreign Royal family members and heads of state. Thousands of well-wishers from around the world have also flocked to London to witness the spectacle and pageantry of the Royal Wedding and street parties are being held throughout the UK. (Photo by Tom Dulat/Getty Images)

British artist, Mark Coreth sits on top of the “Sydney Ice Bear” carved from a 10 tonne block of ice to illustrate how humans affect climate change in the Arctic at Customs House on June 3, 2011 in Sydney, Australia. The public will be welcomed to touch the bear, and leave an imprint which will begin the melting process and act as a metaphor for how humans affect the environment. The ice bear's has visited six cities on it's global tour since 2009; the visit to Sydney coincides with World Environment Day on June 5. (Photo by Lisa Maree Williams/Getty Images)

Retired teacher Geoff Ostling displays his tattooed skin at a portrait session at his home in Petersham on May 11, 2009 in Sydney, Australia. The 62-year old has pledged to donate his skin to the National Gallery in Canberra after his death. Ostling, who did not get his first tattoo until he was in his forties, is now covered in the artwork by artist eX de Merci from neck to ankle with the theme 'all the flowers of a Sydney garden'. (Photo by Lisa Maree Williams/Getty Images)

“A guide horse is an experimental mobility option for blind people who do not wish to or cannot use a guide dog. They are provided by The Guide Horse Foundation, founded in 1999 to provide miniature horses as assistance animals to blind users living in rural environments”. – Wikipedia

Photo: Shari Bernstiel, of Lansdale, Pennsylvania is helped along the sidewalk by Tonto, her guide horse March 19, 2004 in Lansdale, Pennsylvania. Tonto, a minature horse who went through one year of training, acts as Sheri's seeing eye dog and is one of three working guide horses in the United States. (Photo by William Thomas Cain/Getty Images)

Second World War veteran 90 year old William Walker launches the Scottish Poppy Appeal, together with soldiers from the Royal Highland Fusiliers, 2nd Battalion the Royal Regiment of Scotland, on October 27, 2011 in Penicuick, Scotland. Mr Walker, who was wounded while serving in Burma in 1943 with the Royal Scots, helped the soldiers form the shape of ninety to celebrate the 90th anniversary of the annual November campaign. (Photo by Jeff J Mitchell/Getty Images)