Hidden Britain category winner. Garden Spider by Alan Smith from Reading, Berkshire. (Photo by Alan Smith/British Wildlife Photography Awards/PA Wire Press Association)

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

Ten finalists capture the theme of “through young eyes” in this young photographers’ competition that aims to engage youth around the world in wildlife conservation. Here: Heavy bodied jumping spider by Md Rashuidul Rabby, age 23, from Bangladesh. (Photo by Md Rashuidul Rabby/WWD2017)

A zebra walks through the recently flooded Safari Park located at Safari World November 2, 2011 in Bangkok, Thailand. (Photo by Paula Bronstein /Getty Images)

Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

Nosy neighbour by Sam Hobson, UK. Sam knew exactly who to expect when he set his camera on the wall one summer’s evening in a suburban street in Bristol, the UK’s famous fox city. He wanted to capture the inquisitive nature of the urban red fox in a way that would pique the curiosity of its human neighbours about the wildlife around them. (Photo by Sam Hobson/2016 Wildlife Photographer of the Year)

This year’s overall winner and winner of the coast and marine category is George Stoyle with his image “Hitchhikers” of a Lion’s mane jellyfish, photographed at St Kilda, off the Island of Hirta, Scotland. (Photo by George Stoyle/British Wildlife Photography Awards 2016)

Highly commended birds : Crested guan by Tim Hunt (UK). ‘This photo shows a crested guan in the cloud forests of Costa Rica as it pauses while foraging on a lone branch. Due to the clouds that are so typical for this habitat, I could often only photograph the bird’s silhouette against a grey sky. But then, for a short moment only, the sun broke through the clouds, and I overexposed the image by over two stops in order to blow out the background and allow this beautifully marked bird to stand out’. (Photo by Tim Hunt/GDT European Wildlife Photographer of the Year 2015)