It’s one of the toughest investigative assignments here at Vetstreet: track down the most adorable zoo babies of the year for one photo gallery packed with cuteness in epic proportions.

Yes, digging through all of those painfully adorable photos is hard work, but someone has to do it.

So click through the photos below to see some of our favorite baby faces of 2013. If we missed a cutie that you’re particularly fond of, you can share it in the comments section.

Blue-Eyed Lemur

Blue-Eyed Lemur

A critically endangered lemur with turquoise eyes was born in April at the La Palmyre Zoo in France — and needed special care to ensure her survival. The little girl was weak at first and didn’t cling well to her mom, so her keepers decided to hand-rear her. They wanted to keep open the option to reunite her with her parents, so they kept the baby in an incubator and moved her mom and dad to a spot where they could see her through a window.

Panda Cubs

Panda Cubs

Mei Lun and Mei Huan are the first giant panda twins to survive in a U.S. zoo. The pair was born to mom Lun Lun and dad Yang Yang in July at Zoo Atlanta. Until a few weeks ago, officials thought they were boys — but then DNA testing revealed that they’re actually girls. The zoo used a technique known as twin swapping to help Lun Lun through the early months with her babies, keeping one with her and one in the nursery and then swapping them to be sure they were each getting enough to eat and had the chance to bond with mom.

Ocelot

Ocelot

The May arrival of this newborn dwarf leopard was a happy surprise for keepers at the Cameron Park Zoo in Texas. At age 14, mom Maya was past her breeding prime, and efforts to artificially inseminate her with sperm from 6-year-old mate Gustavo had failed several months earlier. On the morning of May 31, Maya stayed in her night house, and her keepers thought she wasn’t feeling well. They were shocked when they found a kitten with her! Maya’s keepers surmised that the ocelot couple had decided to do things “the old-fashioned way,” and they were thrilled to welcome little Aztec.

Sumatran Tiger

Sumatran Tiger

Look at that belly! This beautiful and rare baby girl was born to mom Leanne on Feb. 10 at the San Francisco Zoo. The critically endangered cub grew quickly because of her mom’s great care and a lack of “competition at the ‘milk bar,’” officials said. Leanne was protective of her cub while still encouraging her to venture out of her nest box. There are only an estimated 400 Sumatran tigers living in the wild. 

Polar Bear Cub

Polar Bear Cub

Little Luna was born at the end of 2012, but she made a big splash with her adorable March debut at the Buffalo Zoo in New York. The fluffy white bear was hand-raised. In the spring, she was joined by Kali, a cub of about the same age who was orphaned in Alaska. 

Panther Kitten

Panther Kitten

Unlike the other babies on this list, this sweet face actually belongs to a baby who was born in the wild — but we couldn’t resist including her. Florida Fish and Wildlife officials found the then 1-month-old Florida panther in late June, near the site where her rehabilitated mom was released a few months earlier. They think her mom must have become pregnant about three weeks after she was released. “Kitten survival rates are pretty low, but this kitten looked healthy and feisty,” said Dave Onorato, FWC panther biologist.

Clouded Leopards

Clouded Leopards

Which ones are stuffed and which are real? Three endangered clouded leopard cubs were born at the Nashville Zoo in March and got to explore the outdoors for the first time at 7 weeks old. While they were romping around outside, their keepers surprised them with some stuffed animals to play with, and even more cuteness ensued. One male and one female were born to mom Baylie, and the third cub, another female, was born to mom Jing Jai. All three are being hand-reared at the zoo. 

Spectacled Owlet

Spectacled Owlet

Whooo’s there? Keepers at the Phoenix Zoo were surprised when an egg belonging to a 20-year-old spectacled owl and her 15-year-old mate hatched in February. They weren’t expecting it to be fertile because of the veteran parents’ ages. They knew the chick had arrived when they heard the little noises it made, but they couldn’t catch a glimpse of it until two months later, because mom and dad would fly at the heads of the staff if they got near the nest box. They finally got to see the fluffy white chick when it took a seat in the opening of the nest box in April.

Mini Antelope

Mini Antelope

A baby klipspringer, or mini antelope, was born at the Lincoln Park Zoo in Chicago in early August. Zookeepers had to step in to help raise the baby when its mom didn’t give it the proper care. The species is native to Central and Eastern Africa and will only reach about 20 inches and 24 pounds when it’s full grown.

White Rhino

White Rhino

He’s off! Our final pick is a bouncing baby southern white rhinoceros, who was born at the San Diego Zoo Safari Park on Feb. 25 while visitors looked on. The calf weighed 125 pounds at birth but could grow to be 4,000 to 5,000 pounds once he’s full grown. The newborn was named Kayode, which means “he brings joy.”

See more Vetstreet articles featuring zoo babies.

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