National Geographic invites photographers from around the world to enter its 2017 Nature Photographer of the Year contest. Photos can be submitted at natgeo.com/photocontest in any or all of four categories: Wildlife, Landscapes, Underwater and Aerials.

The grand-prize winner will receive $10,000 (about £7,500), publication in National Geographic Magazine and a feature on National Geographic's Instagram account, @natgeo. Entries close on Friday 17 November 2017, and the winners will be announced in December 2017. For details and official contest rules, please visit natgeo.com/photocontest. IBTimes UK showcases some of the most spectacular entries submitted so far.

National Geographic Nature Photographer of the Year
Skye by Neil Jackson: "A spectacular sunrise at the Old Man of Storr, on the Isle of Skye, Scotland"Neil Jackson / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Whale Shark in Thailand by Dan Charity: "The young whale shark was swimming in the Gulf of Thailand at a popular dive site called Sail Rock near the island of Koh Pha Ngan. The brief encounter was captured whilst diving the reef which the graceful giant was using as cleaning station, a sort of car wash for big fish."Dan Charity / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Family Reunion by Sonalini Khetrapal: "We found them early one morning feasting on a new kill of a springbok. It was an intense sight to watch them feed – our close proximity to them gave us an opportunity to observe their relationship with one another. It was fascinating to watch the brothers intermittently embrace each other and lick the blood off each other’s faces while the mother kept guard. This photograph captures the harshness of the wild and yet softens us to witness the strong bond between the brothers."Sonalini Khetrapal / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Sea and Salt by Wellington Rodrigues: "Spain has many impressive landscapes and fascinating destinations, but one of the most amazing natural resorts are the salty pink lakes in Torrevieja. In this beautiful coastal resort you can find two beautiful salt lakes: a blue-green one called La Mata lagoon and the other, of an impressive pink colour, known as Torrevieja lagoon; both connected to the sea by canals."Wellington Rodrigues / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Above the Polar Bear by Florian Ledoux: "Dear future generation, I hope we will still be able to see the Arctic wildlife as we do now. It is threatened as the environment is changing. I was able to witness many scenes of wildlife and I can guarantee you this is the most beautiful thing I have ever seen. Here the polar bear might be interpreted as holding back the sea ice melting. Incredible and unique shot six metres above a polar bear in Nunavut, Baffin area during wildlife reportage in Nunavut and Greenland during summer 2017."Florian Ledoux / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Kalsoy by Wojciech Kruczyński: "Kalsoy island and Kallur lighthouse in sunset light, Faroe Islands"Wojciech Kruczyński / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Great Grey Owl Taking Off in Winter by Tin Sang ChanTin Sang Chan / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Sunrise  by Witold Ziomek: "Morning at Koruldi Lakes in Georgia (the country)."Witold Ziomek / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
One happy seal model by Lars Lykke: "Went to the very north of Denmark, Skagen, at sunrise and found this willing model."Lars Lykke / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Great White Shark by Alejandro Cupi: "Great White Shark at Guadalupe Island, Mexico"Alejandro Cupi / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
A Beautiful Morning in Hallstat by Shanof K: "The image was taken from the village of Hallstat in Austria right after sunrise. I had to walk some distance to reach this village view point. It was worth every step that I took as the scene turned out to be magical with the fog movement. Luckily the fog did not cover up the mountains."Shanof K / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Liquid bear by Mike Korostelev: "Bear from the water Kamchatka, Russia"Mike Korostelev / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Lions quarrel by Aaron Baggenstos: "A male African lion teaches a lesson to a hyena pack for trying to steal its kill."Aaron Baggenstos / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
I can see the sky from here by Anders Andersson: "My daughter and her best friend on their backs in a clearing, just between planted fir forest and natural beech forest"Anders Andersson / National Geographic Nature Photographer of the Year contest
National Geographic Nature Photographer of the Year
Iceflowers by Stefan Thaler: "This photo was made in my hometown, called Thiersee, a small village in the heart of the Alps (Tyrol, Austria). I had to wait till the lake Thiersee, which is frozen all the wintertime, begins to melt in spring. Just for a few days you can see these natural patterns in the melting ice.but not without a drone. I told my daughter to make a boat trip with her red kayak."Stefan Thaler / National Geographic Nature Photographer of the Year contest