The 2016 National Geographic Nature Photographer of the Year contest officially kicked off in August and is now in full swing. Nat Geo is looking for pictures that showcase the diversity of the natural world around us in four categories: Animal Portraits, Environmental Issues, Action, and Landscape.

If you have a great picture that fits one of the categories, you can enter the contest here. Submissions will be accepted until November 4. There is no limit to the number of pictures you can submit, but there’s a $15 entry fee for each photo.

The grand prize is a 10-day trip for two to the Galapagos and two 15-minute image portfolio reviews by Nat Geo photo editors. There are also cash prizes for the first, second, third-place winners from each category.

Every week, editors pick their favorite submissions from each category. Below are 15 of our favorite entries from the Animal Portraits category with their original captions.

1. Arctic Illusion

“Polar bears are tied to the sea ice for nearly all of their life cycle functions. Over the past 25 years, the summer sea ice melt period has lengthened, and summer sea ice cover has declined by over half a million square miles.” Taken by Chris Schmid in Longyearbren, Svalbard, Norway.

2. NEVER bother Dad when he’s sleeping

“During our trip to Botswana, we came across two lionesses and their six cubs, resting under a bush during mid-day. This male lion came along to visit the den. The females were very wary at first. We were told that a male lion will kill cubs that aren't his offspring. Fortunately, he laid down with the cubs and closed his eyes to sleep. The cubs were VERY excited to see their Dad! This little guy was trying so hard to get him to play! Dad was definitely NOT happy to be woken up.” Taken by p. Kuhn in Botswana.

3. Proud Momma

“Fry of a Peacock Bass hover around their mom for protection against predators. Peacock Bass, part of the Cichlid family, exercise excellent parental car and will protect their young against any threat that approaches them. This tropical species from South America was intentionally introduced in South Florida during the 1980s to control the African Tilapia, another invasive species.” Taken by Michael O’Neill in South Miami, Florida, United States.

4. Black Oystercatcher

“These Black Oystercatchers like to feed on marine invertebrates, particularly mollusks. It hunts through the intertidal area, searching for food visually, often so close to the water's edge it has to fly up to avoid crashing surf.” Taken by Gary Migues in Trinidad, California, United States.

5. Cape Buffalo with Yellow-billed oxpecker

“I had been wanting to get this image for at least two years and just recently, on my last safari in November, was able to successfully capture it. Many aspects came into play for my reward. Light was key. Side-light, lighting the Oxpecker and keeping the Buffalo in the shade was crucial. I wanted a darker pallet for this image, and think I got it. I captured both subjects in focus, very difficult to do as both were moving and in different focal planes.” Taken by Barbara Fleming in Ngorongoro, Arusha, Tanzania.

6. Great Egret against the setting sun

“A Great Egret (Ardea alba) waiting for its mate to return in the evening. The light was amazing and just right so that it is just not a silhouette (I got some silhouettes a little later!). This is during the breeding season for these birds and they develop these long plumes (aigrettes) and a neon green color on their face that are seen in this photograph.” Taken by Arun P. in Charleston, South Carolina, United States.

7. Two plus four 7

“Aptenodytes forsteri. Emperor Penguin. Antarctica, on frozen ice. We were camping on 3 m thick frozen sea water, just 1.5 miles away from a big emperor penguin colony, with lots of mega cute chicks. I concentrated especially on taking images of the adorable chicks in the harsh conditions of their environment. The image shows several emperor penguin chicks in front of adult penguins to shield from the forces of the storm.” Taken by Gunther Riehle in Snow Hill, Antarctica.

8. Mother Ostrich

“A mother ostrich is watching over her chicks in the savannahs of Africa.” Taken by Yu Huiping.

9. Tripodfish

“I recently discovered this Tripodfish, Bathypterois grallator, a larval fish during a "black water" scuba diving expedition to document vertical migration marine creatures. This is done in the South Atlantic Ocean, Gulfstream current, The tripodfish or tripod spiderfish, Bathypterois grallator, is a deep-sea benthic fish, known mostly from photographs from submersibles. This fish comes up from the depths of 2,400 feet to 15,000 feet during a vertical migration occurring in the ocean.” Taken by Suzan Meldonian.

10. Moving at a snail’s pace…

“While enjoying the sights of Chicago's Garfield Conservatory found this unlikely traveler taking a closer look at this Bromeliad. Sometimes you have to slow down to appreciate the tiny wonders right in front of you!” Taken by Samira Qadir in Chicago, Illinois, United States.

11. Mediterranean Jelly

“Cotylorhiza Tuberculata, aka Mediterranean Jelly or (more friendly...) Fried Egg Jelly, is pretty common throughout Mediterranean Sea. Its stings are totally harmless to humans yet its beauty is absolutely contagious.” Taken by Stefano Spezi in Fano, Italy.

12. Brown Bears

“Brown Bears, Katmai National Park, Alaska.” Taken by Aaron Baggenstos.

13. Indomitable

“A polar bear mother and her newborn cubs relax on an iceberg on the coast of Baffin Island, Canada.” Taken by Jonathan Huyer in Qikiqtarjuaq, Nunavut, Canada.

14. Adelie penguin jumping between ice floes

“I saw these Adelie penguins jumping into the water at Brown Bluff on the Antarctic Peninsula. By the time I sat down on the beach to take a picture, they'd starting jumping to the next ice floe. Paul Goldstein says the Holy Trinity of wildlife photography is 'dust, air and spume', and this shot captures the 'air' bit!” Taken by Nick Dale in Snow Hill, Antarctica.

Read More