The staff battle to save a vulnerable chick, a portly penguin is put on a strict diet, and in home pen a juvenile of unknown gender gets some important test results.

Amputee Cedric's happy marriage to Robin faces its biggest challenge. Squeaker tests people's patience and a wild penguin comes in with a life-threatening wound.

Investigators find a young puppy suffering without water or shelter. Meanwhile, a tourist attraction has an unwanted visitor - a wild alligator.

Game Warden Benge returns after a life-threatening injury. Along the coast, fishermen get caught with too many sharks and a protected turtle gets relocated.

As new predators encroach on the ranch, the Browns devise inventive solutions to defend their livestock. Gabe's long-distance girlfriend makes her first visit.

A medical emergency on the Wolfpack's ranch forces them to be more resourceful. And, Gabe's family are concerned when he makes a hasty leap towards marriage.

Experts test to see if wild wolves are smarter than domestic dogs with an interesting experiment. Plus, can spiders really fly? And, how do polar bears keep warm?

Experts look at why ants don't drown. Why don't woodpeckers get headaches? And, how does a 15-foot octopus escape through a three-inch hole?

An emaciated dog is brought into the centre weighing only a third of a healthy bodyweight, and the team quickly discovers its owner also needs their urgent help.

An undercover investigation leads the team to a shocking discovery: eight dogs tied to metal chains as well as dog-fighting paraphernalia, illegal drugs and a gun.

A shocking case of animal cruelty arrives at the Pennsylvania SPCA: a Labrador named Clyde has been attacked by another dog and left without veterinary care.

School is in full swing and in just a few months the students will be doctors. Adding to the stress they must first pass their final rotations.

In the arid scrubland of Tinaja, New Mexico, Bradley and Billy track down the giant scolopendra centipede. Armed with venomous claws, it's a relentless killer.

Bradley and Billy are in Great Karoo, South Africa, searching for a majestic micro-dragon - the armadillo girdled lizard. It has a formidable defence mechanism.

The vets treat Xena, a German shepherd with head injuries after being trampled by a donkey. And, Coco the kitten is having trouble walking.

Nalla the dog needs emergency treatment after being shot in a home invasion. Plus, Dr Jeff and Hector treat wolves at a Colorado wildlife sanctuary.

Terri welcomes Mballa, a new cheetah cub from South Africa, to the Australia Zoo family. Meanwhile, Robert sets out to save a stranded platypus.

Love is in the air at Australia Zoo! Terri helps determine if Caballe the Rhino is pregnant, while Robert matchmakes the zoo's Aldabra giant tortoises.

A curious and active box turtle goes for his daily walk and two wobbegong sharks are due for a check-up. Plus, the staff prepare for puffin breeding season.

Earl returns from rehab, hoping to rebuild his life working with the dogs. Plus, Lizzy rescues a dog after a confrontation with the owner who abandoned it.

A couple is unable to move in together because of their violent cats. Plus, a war veteran whose feline reacts violently towards his girlfriend's dog seeks advice.

Pete designs a treehouse fit for the ultimate survivalist. He designs a camouflage structure with a luxurious interior that could pamper any hardened champion.

Pete works his magic in Georgia to build a treehouse the breaks all the country rules, and then visits racing legend Dale Earnhardt Jr.'s own treehouse.

On one of his most audacious and exciting expeditions to date, Forrest travels to the remote Galapagos Islands in search of the fabled Fernandina tortoise.

The guys are challenged to build a tank guarded by sharks inside a vault. Plus, can they create a bi-level Koi fish pond for NFL star Scott?

Take a look back at the tanks ATM have built that were inspired by moments in history, including a 1920s mob-themed tank and a 1960s lava lamp tank.

Baseball legend Pete Rose wants Riverfront Stadium transformed into an aquarium. Later, Wayde and Heather travel to Horry County to build a huge aquarium.

Neil defies both nature and locals by developing his mine tour. But when the town discovers his secret construction project, McCarthy draws a line in the sand.

Rover a young working dog, who has fallen over a cliff, is brought into the hospital. Surgeon Annette operates successfully but when Rover relapses can he be saved?

After a devastating earthquake, Marty saves a log cabin from crumbling to the ground while Misty replaces a collapsed greenhouse and Matt constructs a new building.