Terri returns to her hometown in Oregon to help Brady, a cougar in need of a vital health check; at the zoo, Robert is on a mission to rescue Oscar, a small bird with a big attitude; Bindi bathes an echidna with bad skin allergies.

A 12-foot alligator stalks farm animals; an elusive gator moves into a neighborhood pond; a triple-amputee war veteran wants to wrestle an alligator.

A water moccasin is spotted near a home; 6-foot-long rattlesnake; Paul and Scott pull a prank on Ashley and Chris.

Former reality star Peggy Tanous is struggling to keep the peace between her cat Shadow and her family. Meanwhile, a couple is desperate for Jackson to change the frisky behavior of their feline, Albert.

When Debbie returns home from a trip, she finds her house covered and smelling like cat pee from her boyfriend, Brian's cat Blinkie, who denies the problem;Krisi may have to choose between marriage to her boyfriend Jason and her cat Frankie.

The police need Villalobos' help when a woman in the French Quarter is rushed to the hospital, leaving her dogs behind; a recent divorcee from Alabama visits the rescue to help fill the void in his home; Rhino faces a health crisis.

Remembering the first pit bull that Tia rescued, and the dog that walked Tania down the aisle; the family looks back at the most memorable dogs.

Pete has one week to build a Christmas-treehouse wonderland in the desert outside Jamul, Calif., for a family who celebrates Christmas 365 days a year; members of the Fraternal Order of Real Bearded Santas lend a helping hand.

Pete uses hand-hewn rustic cedar to build an African-inspired circular hut treehouse complete with aerial walkway, spiral staircase and thatched roof.

Adventure-themed treehouse with suspension bridges, rock-climbing wall and hidden passages is built in the Pocono Mountains.

Pete builds a high tech recording studio oasis up in the trees that perfectly blends into the heart of the outdoors. CeeLo Green soon arrives to lay down a brand new track upon completion.

Pete builds a butterfly-themed treehouse that includes six trees in Independence, Ohio, for a hope center that wanted a therapeutic space within the trees.

The team attempts to construct a chic but Bohemian tri-level, 60-foot-high treehouse in three giant redwoods for an arborist in Humboldt County, Calif.

Pete creates his first-ever midcentury decagon when he builds a tree house to observe bears in Farmington, Pa. -- complete with walls of glass windows and a "bear-cam" tracking system.

Pete builds a 600-square foot Western-style man-cave tree house that includes a cigar humidor, a meat smoker, and a flat-screen TV, for a father of three daughters in Texas.

A couple dreams of having a treehouse atop a lighthouse in Washington, and Pete finds the property's steep grade challenging.

The team attempts to construct a chic but Bohemian tri-level, 60-foot-high treehouse in three giant redwoods for an arborist in Humboldt County, Calif.

Pete creates his first-ever midcentury decagon when he builds a tree house to observe bears in Farmington, Pa. -- complete with walls of glass windows and a "bear-cam" tracking system.

Pete builds a 600-square foot Western-style man-cave tree house that includes a cigar humidor, a meat smoker, and a flat-screen TV, for a father of three daughters in Texas.

A couple dreams of having a treehouse atop a lighthouse in Washington, and Pete finds the property's steep grade challenging.

Pete uses hand-hewn rustic cedar to build an African-inspired circular hut treehouse complete with aerial walkway, spiral staircase and thatched roof.

Adventure-themed treehouse with suspension bridges, rock-climbing wall and hidden passages is built in the Pocono Mountains.

A 150-foot long super snake known as the Yacumama attacks and kills people in Peru; the villagers fear it so much they try to blow up the creature with dynamite.

Investigating a bigfoot-like creature with superhuman strength reported in the foothills of the Andes; Mungo hears chilling yet conflicting stories on the Ucumar: some believe the creature is a bear, while others think it's more of a yeti.

Jackson and Zoe meet Tami, whose two terrorized cats have been outfitted with a rooftop cat sanctuary, complete with scratching posts, food and water stations and lawn chairs.

To prevent a couple's third breakup, Jackson assists Terence, who needs to overcome his feline fears; Zoe works with the couple's Rottweiler.

A couple want to move in together, but their pets don't get along; a stressed cat licks her belly raw.

The zoo staff works to build a relationship between a pair of Asian elephants with very different personalities; vets treat an ocellated turkey chick's foot condition; Isabella the North American beaver undergoes a tooth trim.

Howie the rescued wallaby is ready to be relocated to Arizona, where he will meet his new mob and potential mates; red river hogs Hampton and Athena are paired for breeding; little penguin Jaffa must undergo eye surgery to restore his vision.

When Matthew the feisty camel develops a tooth issue, the zoo staff is determined to treat him; Ivy the babirusa is expecting for the very first time; one keeper builds a bond with a Magellanic penguin chick reluctant to be hand-fed.

The zoo's medical team must perform critical surgery on a bison calf born with a bowed leg; three lynx kittens are ready to explore their exhibit; the first known U.S. case of COVID-19 in animals is confirmed when a Malayan tiger tests positive.

A gorilla must undergo a critical root canal to fix its tooth problem; a red-crested turaco chick fledges the nest; a pair of puma cubs travel to their new home at the Queens Zoo.

When Kip the young silver langur falls ill, he must be nursed back to health; Cora, the white-naped crane chick, is relocated and introduced to her potential mate; giraffes Jigsaw and Zizi are paired for breeding.

After a long road to recovery, a golden eagle is ready for its debut at the Eagle Aviary exhibit.

Denver's busiest vet returns in a new clinic with more patients than ever before; Dr. Jeff fights to help a dog walk again; Dr. Amy operates on a cat with a strange appetite; the team heads out to a sanctuary to help an injured tiger.

Dr. Jeff battles to fix a German shepherd's broken elbow and get him back to his worried owner, a disabled war veteran; a cat with a swollen bladder needs difficult surgery to save its life; Drs. Baier and Hector head to an exotic bird sanctuary.

Dr. Jeff and Dr. Petra work together as they battle to save the leg of a beloved husky; Dr. Baier has a scare when a routine pig spay becomes complicated; a cat with potentially fatal bladder stones gets rushed intro surgery.

Dr. Jeff operates on a dog rushed to the clinic after a growth on her neck ruptures; a family brings in a rabbit with mysterious growths on its side; the team performs a risky procedure on a pair of rescued miniature donkeys.

Dr. Dee and her husband Ken host a clinic in a town with a population of 107; back at Animal House, Dr. Dee races to save an akita with a gunshot wound.

Dr. Dee has to be careful when she visits a ranch to check on a pack horse named Red; Dr. Terry and Nicole head to a remote clinic; dog has a mass that appears to be cancerous.

Dr. Jeff and Dr. Petra work together as they battle to save the leg of a beloved husky; Dr. Baier has a scare when a routine pig spay becomes complicated; a cat with potentially fatal bladder stones gets rushed intro surgery.

Dr. Jeff operates on a dog rushed to the clinic after a growth on her neck ruptures; a family brings in a rabbit with mysterious growths on its side; the team performs a risky procedure on a pair of rescued miniature donkeys.

Dr. Dee and her husband Ken host a clinic in a town with a population of 107; back at Animal House, Dr. Dee races to save an akita with a gunshot wound.

Dr. Dee has to be careful when she visits a ranch to check on a pack horse named Red; Dr. Terry and Nicole head to a remote clinic; dog has a mass that appears to be cancerous.

When Kip the young silver langur falls ill, he must be nursed back to health; Cora, the white-naped crane chick, is relocated and introduced to her potential mate; giraffes Jigsaw and Zizi are paired for breeding.

After a long road to recovery, a golden eagle is ready for its debut at the Eagle Aviary exhibit.

A woman and her family spend their time rescuing and rehabilitating koalas in their home in Australia; Crikey the koala, a baby found alone and very sick, becomes well enough to release back into the wild.

Katherine Conner drops out of school at 16 to work as a professional dancer in London's West End, her life's dream; at the age of 21, while on vacation in Thailand, she meets a baby elephant named Boon Lott that changes her life forever.

Sgt. Simmons investigates the killing of a mother deer; Warden Curtis and police dog Cruizer search the backwoods for a missing hunter.

Warden Miller and Sgt. Annis encounter a family with weapons in its car and a strange ATV driver; Cpl. Clowery patrols Maine's white-water rivers.

The game wardens take to personal watercraft and speedboats to patrol Maine's thousands of rivers and lakes.

Sgt. Simmons joins forces with associates from other agencies to track down a notorious deer poacher.

The wardens travel to a southern Maine wetland where they catch hunters using illegal guns, ammunition and drugs.

The wardens split their time patrolling the water and the woods during the end of summer; criminals conduct illegal drug activity in the wilderness.

The game wardens face extra work during the summer tourist season; Sgt. Craven stops a runaway ATV and tries to determine which of two duplicitous friends is telling the truth.

When the openings of both the bighorn sheep and archery elk hunting seasons overlap, wardens catch illegal hunters in the act; off-roaders cause some serious land damage; on the 4th of July seemingly intoxicated boaters give wardens a difficult time.

Wardens use new aircraft to patrol from above; on the ground, wardens experience a crazy weekend during the Yellowstone Boat Float and ensure participants comply with the law; their coordinated efforts enhance safety and order in the region.

A look at the lives of Montana conservation officers who defend public lands, handle anti-poaching sting operations and more.

Wardens in Region 2 respond to a TIP Mont call about a potential elk violation, conducting a detailed investigation; in Region 4, a warden assists hunters in recovering a wounded deer, ensuring proper procedures are followed.

Wardens tackle elk harassment, illegal shootings and rescue a deer.

Wardens help rescue a hunter with a broken leg. Hunters coming through a warden check station get into hot water after not telling the truth.

Wardens tackle poaching, missing elk and unauthorized campers.

Discovering the lives of conservation officers of Montana defending public lands, handling antipoaching sting operations, and more.

Wildlife decoys lead to surprising arrests; a warden's K9 unearths critical evidence; a major investigation into moose and elk poaching results in a significant law enforcement takedown.

Wardens help rescue a hunter with a broken leg. Hunters coming through a warden check station get into hot water after not telling the truth.

Wardens tackle poaching, missing elk and unauthorized campers.

Discovering the lives of conservation officers of Montana defending public lands, handling antipoaching sting operations, and more.

Wildlife decoys lead to surprising arrests; a warden's K9 unearths critical evidence; a major investigation into moose and elk poaching results in a significant law enforcement takedown.

Wardens use new aircraft to patrol from above; on the ground, wardens experience a crazy weekend during the Yellowstone Boat Float and ensure participants comply with the law; their coordinated efforts enhance safety and order in the region.

A look at the lives of Montana conservation officers who defend public lands, handle anti-poaching sting operations and more.

The Thrift Store crew is left shocked by the aftermath of the accident as donations flood in; Allison takes home a patient to make sure he doesn't take a turn for the worse.

Dr. Schwartz is on a mission to hunt down the remains of a tin can that lies within the intestines of an anxious-ridden Labradoodle.

Robert and Terri take to the skies to release three rescued sea turtles near the Great Barrier Reef; Bindi anxiously awaits the birth of the zoo's first tiger cub in years; Richie helps a baby wallaby in his struggle for survival.

A nuisance call leads to a dangerous encounter with two bloodthirsty lizards; Tre and Jimmy bring alligators to a saloon.

The Gator Boys leave Everglades Holiday Park; Jimmy locates an alligator ranch in Mississippi; Paul has a big decision to make.

A woman's cat Pip is a one-eyed feline with cerebellar hypoplasia who torments her other cat, Red; a little girl's birthday present named Autumn is destructive to their home and targets the couch, beds, computer monitor and microwave.

Buddy's owners are determined to transform him into the perfect indoor cat, despite his aggressive tendencies; Kali was recently adopted but due to her terrorizing behavior she may end up back in the shelter.

Tia and the twins search for a dog abandoned in the swamps; a young parolee has a hard time coping with the stress of work and parenthood.

Tragedy results when Tia and Mariah help a man care for two rescued animals; a Villalobos volunteer wants to adopt a dog with a strange past.

Robert and Indah, a Komodo dragon, participate in an exciting research experiment; Terri tries to save a koala joey with a zero percent chance of survival; Bindi visits friends at childhood favorite spot Oregon Coast Aquarium.

Bindi and the keepers ready Sophie the Baby Giraffe for her first steps into her enclosure; Robert helps to hand-raise Melman the Kangaroo; Terri oversees a health check for Ravi the Red Panda.

The Irwins travel to South Africa, where Terri helps release a wild leopard; Bindi learns from the all-female anti-poaching squad, The Black Mambas; Robert attempts to photograph Africa's big five game animals.

The family prepares Croc One, Steve Irwin's research ship, for a mission to release an endangered sea turtle back to the wild; Scarlett the giraffe reunites with her grandmother; Grub the wild echidna is released from the Zoo's Wildlife Hospital.

As Bindi celebrates her 21st birthday, she gets a surprise proposal from her boyfriend, Chandler; things get dangerous as Robert wrangles gators in thick mud; Terri helps with the momentous birth of a baby white rhino.

In Alaska, Noah risks losing a dream property when he volunteers his siblings and himself for a hauling-and-build mission to help an off-grid family in need; Bear invents a new way to accomplish a tedious bush chore.

The Brown siblings battle boat issues while racing to meet a deadline to see a dream property; in Washington, Bam strives to save the ranch money by learning from a local hay farmer; Bear and Raiven share big news for their future.

The Browns must navigate the treacherous Wrangell Narrows on course for the storied Mosman Island, where Bird hopes to begin a new chapter; with the clock ticking for Noah to find his homestead, stormy seas threaten their journey.

Noah finds his dream property on a remote, private island but without the full deposit to secure it, agrees to a complex barter deal; back on Mosman Island, the emotion of the Alaskan trip takes its toll on youngest sibling Rain.

In Alaska, Noah risks losing a dream property when he volunteers his siblings and himself for a hauling-and-build mission to help an off-grid family in need; Bear invents a new way to accomplish a tedious bush chore.

The Brown siblings battle boat issues while racing to meet a deadline to see a dream property; in Washington, Bam strives to save the ranch money by learning from a local hay farmer; Bear and Raiven share big news for their future.

The Browns must navigate the treacherous Wrangell Narrows on course for the storied Mosman Island, where Bird hopes to begin a new chapter; with the clock ticking for Noah to find his homestead, stormy seas threaten their journey.

Noah finds his dream property on a remote, private island but without the full deposit to secure it, agrees to a complex barter deal; back on Mosman Island, the emotion of the Alaskan trip takes its toll on youngest sibling Rain.

Bindi and the keepers ready Sophie the Baby Giraffe for her first steps into her enclosure; Robert helps to hand-raise Melman the Kangaroo; Terri oversees a health check for Ravi the Red Panda.

The Irwins travel to South Africa, where Terri helps release a wild leopard; Bindi learns from the all-female anti-poaching squad, The Black Mambas; Robert attempts to photograph Africa's big five game animals.

The team must create a samurai-themed enclosure for two boa constrictors in time for the grand opening of Serpent Tattoo; Rachel is forced to confront her fear of snakes when the team collaborates with a rattlesnake wrangler.

The team create a gangster-themed enclosure for seven snakes; a Russian tortoise name Littlefoot gets a new home;. when Greg takes Kevin to the veterinarian, the results are a bit surprising.

After months of croc-wrangling training with Steve Irwin's best friend Wes, Robert, Steve's son, takes the final step in his journey to feed Graham, a huge crocodile at the zoo's famous Crocoseum.

The boys rescue a creepy-looking alligator; Jimmy battles a canebrake rattlesnake; Ashley becomes the marketing director of the Gulf Coast Gator Ranch.

A baby alligator with a taped-shut jaw roams a nearby creek; the closing of Everglades Holiday Park could spell the end of the Gator Boys.

Penny is an aggressive feline who has her owners desperate to restore peace in the home; Tony is a cat who displays bizarre and malicious behavior, leaving his care takers puzzled and eager for Jackson's help.

A little girl's cat Moose has suddenly become territorial and her parent's are desperate for Jackson to change his ways; a couple have adopted Kimba, a rambunctious feline who has terrorized the home since day one.

Memphis Grizzlies basketball star Zach Randolph contacts Tia about a dog that was rescued from a drainpipe; Mariah and Earl ready a puppy for adoption.

A large family hopes to adopt a new dog after losing their pet to cancer; Tia and Tania encounter a snarling, sick dog in New Orleans' 9th Ward.

It's the start of hunting season, dubbed the holy day for game wardens; Wardens Inman and Eddins investigate the illegal shooting of two deer; Wardens Stapleton and McGee swap out bass in the Bois d'Arc Lake.

Warden Price is on a mission to arrest out-of-state hunters with warrants for trespassing and hunting on private property; a young angler is haunted by his past and is taken to county jail; Warden Richards questions a pair of dishonest fishermen.

During deer hunting season, Wardens Gould and Scott respond to a call about finding carcasses on private property; a horse owner's home is peppered with stray bullets, while hunters are questioned about hunting illegally.

Confronting a suspected duck and goose poacher; monitoring an injured deer running along a highway; a man is arrested after confessing to poaching a deer.

In Llano County, a jet skier's life is spared after an explosion on the water; when a man fakes his own death, Warden Herchman and Stapleton join forces to track him down; a man is found trespassing while fishing.

A tense confrontation ensues when Wardens Scott and Gould respond to a call about an illegal deer hunting case; two raccoons find their way to a gas station and must be trapped; Warden Boone handles a disgruntled hunter at a deer hunting club.

In Texas, a woman is found in distress on the side of the highway; Warden Hensz handles an aggressive family of owls; Warden Bailey responds to a call about underage drinkers holding a fishing tournament.

Confronting a suspected duck and goose poacher; monitoring an injured deer running along a highway; a man is arrested after confessing to poaching a deer.

Warden Cummings deals with an angry man who blew a stop sign; Warden Boone helps chase a trio of armed robbers on the run; Warden Inman investigates a group of suspected deer hunters for trespassing.

A tense confrontation ensues when Wardens Scott and Gould respond to a call about an illegal deer hunting case; two raccoons find their way to a gas station and must be trapped; Warden Boone handles a disgruntled hunter at a deer hunting club.

In Texas, a woman is found in distress on the side of the highway; Warden Hensz handles an aggressive family of owls; Warden Bailey responds to a call about underage drinkers holding a fishing tournament.

Confronting a suspected duck and goose poacher; monitoring an injured deer running along a highway; a man is arrested after confessing to poaching a deer.

Warden Cummings deals with an angry man who blew a stop sign; Warden Boone helps chase a trio of armed robbers on the run; Warden Inman investigates a group of suspected deer hunters for trespassing.

Warden Price is on a mission to arrest out-of-state hunters with warrants for trespassing and hunting on private property; a young angler is haunted by his past and is taken to county jail; Warden Richards questions a pair of dishonest fishermen.

During deer hunting season, Wardens Gould and Scott respond to a call about finding carcasses on private property; a horse owner's home is peppered with stray bullets, while hunters are questioned about hunting illegally.

Cats of the Southwest.

Wild and domestic cats occupy the same sanctuary; popular television cat in Little Rock, Ark.

Robert wrangles Utah, a venomous 12-foot king cobra; Dr. Amber visits Pandora to care for wild koalas; back at the zoo, an old injury flares up for Bruce the brolga, a bird that has been in the Irwins' care for 26 years.

Paul calls in an expert when Allan and Curtis insist Mississippi alligators are stronger than their counterparts from Florida; Sara feels neglected by Jimmy.

The boys search for a legendary 15-foot alligator known as Big Bull; Paul and Chris hope to determine if whips or knives make the better accessory.

A couple who has moved in together have merged the lives of their two cats. Since the move, Buddy has become territorial and a bully; two roommates adopted a cat who destroys and pees on everything in their apartment.

A family is trying to wrangle their cat, Burberry who is deaf, blind and has recently become violent; a couple is eager to start a family but are hesitant due to the aggressive behavior toward their other animals.

Kenani and Moe celebrate their birthday by converting a home in the swamps to a dog sanctuary; when one of Villalobos' beloved dogs gets unexpected news, Tia is determined to have him live out his days with the twins.

Tia races to save a mother dog and her puppies; a major event in the life of a loyal parolee leaves Tia reeling.

California restaurant Mel's Drive In wants a tank for their new location in Santa Monica; the owners want a nostalgic feel and a ton of insert pieces that represent Mel's storied history while pointing to the restaurant's future.

NASCAR driver Kurt Busch and his wife request a little piece of paradise inside their aquarium -- they want to replicate their wedding location.

Howie Mandel reaches out to ATM for another tank, only this time it's a surprise for his manager's company; Three Arts Entertainment already has an existing tank, but it needs a serious upgrade.

Jeremy Wade encounters the Amazon's legendary arapaima, one of the largest freshwater fishes in the world.

Jeremy Wade searches for the Amazon's notorious flesh eaters; a man is swallowed whole by a fish.

Jeremy searches for a modern-day "Jaws" in Florida's Indian River Lagoon and investigates underwater predators in Missouri's Lake of the Ozarks.

Jeremy stalks a rare river beast in Mongolia while minding the armed outlaws in the wilderness.

Jeremy investigates grisly river attacks in the Himalayas, but is warned that the suspected predator is a sacred creature.

Jeremy travels to the Amur River in eastern Russia, where a mammoth predator is allegedly responsible for the disappearances of three fishermen.

Jeremy searches for a modern-day "Jaws" in Florida's Indian River Lagoon and investigates underwater predators in Missouri's Lake of the Ozarks.

Jeremy stalks a rare river beast in Mongolia while minding the armed outlaws in the wilderness.

Jeremy investigates grisly river attacks in the Himalayas, but is warned that the suspected predator is a sacred creature.

Jeremy travels to the Amur River in eastern Russia, where a mammoth predator is allegedly responsible for the disappearances of three fishermen.

NASCAR driver Kurt Busch and his wife request a little piece of paradise inside their aquarium -- they want to replicate their wedding location.

Howie Mandel reaches out to ATM for another tank, only this time it's a surprise for his manager's company; Three Arts Entertainment already has an existing tank, but it needs a serious upgrade.

Ralphie is the only boy when Maltese mix, Coco has a surprise litter at urban animal shelter; Ragdool kitten, Jolene is a hand full for her mom.

A Shetland Sheepdog pup is constantly distracted by Gino the Pomeranian; Charlie is the one Manx in a litter full that has a tail.

Abyssinian kitten gets into all of the craft supplies in her home; Elf kitten Pixie searches for a friend.

A rare litter of Portuguese Podengo Pequeno pups are brought into the world by the resident dog about town, Izzy; Cockapoo octuplets are being trained to be therapy dogs.

Hunter the Sumatran tiger is blind and must be sedated for his annual eye check; the keepers prepare young giraffe Scarlett for a road trip to South Australia, reuniting her with family.

Paul and Jimmy get off to a rocky start in Mississippi; the boys work in sweltering heat to finish a gator pit before the wrestling shows can begin.

Paul makes a bid that could bring the Gator Boys back to Everglades Holiday Park; a photo shoot involving alligators takes a dangerous turn.

A couple has joined the lives of their two felines and are finding it difficult to live in peace due to all the fighting; a woman is at the end of her rope when her cat refuses to use her litter box.

A couple expecting their first child fear that their fairytale life will be derailed due to behavior of their aggressive cat; a woman contemplates becoming an animal behaviorist because of her two terrorizing felines.

A girl needs Tia's help after she saves a pit bull from drowning in a canal; Tia must hire another parolee after 20 new puppies arrive at Villalobos.

Tia addresses her lazy parolees, which leads to a fiery confrontation with Randy; a strange-looking dog is rescued from the searing heat.

Allena Hansen works on her ranch in the California desert with her two rescue dogs when a black bear attacks; in Cancun, Mexico, Jonathan Schoeneman goes spearfishing with his best friend when he comes face to face with a crocodile.

On Christmas Eve, Matt Chenhall is walking with his two young daughters when he is attacked by a kangaroo; Lauren Fagen is volunteering at an animal sanctuary in South Africa when a lion reaches under a gate and pulls her legs through the bars.

While hiking in Alaska, Catherine Dwinnell encounters a 1,000-pound moose that strikes her from behind; in Hawaii, Tony Lee swims a half-mile from shore when something grabs him and drags him below the surface.

Colorado park ranger Andy Peterson is hiking when he crosses paths with a mountain lion and its prey; in Vancouver, Kari Toft is walking her dog just steps from her home when she is attacked by a vicious raccoon.

On a dream trip in Alaska, Greg Matthews and his brothers cross paths with a grizzly bear; in Australia, Ella Murphy and her friends go surfing when a mystery assailant violently strikes her in the head.

Wayne Petteway is attacked by an alligator while checking crab pots with his brother in North Carolina; in Arizona, Peter Baca is camping with his girlfriend and baby son when he is awoken by something attacking him through the walls of the tent.

Nicole Moore's vacation in Cancun, Mexico, gets cut short when a shark attacks her close to shore; in Tennessee, a timber rattlesnake bites firefighter Kyle Watson while he hikes in the woods with his family.

High up on an ice-covered Canadian mountain in the middle of the night, a grizzly bear charges professional climber Greg Boswell; in upstate New York, a rabid coyote attacks a retired nurse.

Twenty miles into a marathon in a remote part of New Mexico, Karen Williams finds herself caught between a bear and her cub; Steve Campbell is working on an oil pipeline in Alberta, Canada, when a mountain lion attacks him.

Wayne Petteway is attacked by an alligator while checking crab pots with his brother in North Carolina; in Arizona, Peter Baca is camping with his girlfriend and baby son when he is awoken by something attacking him through the walls of the tent.

Nicole Moore's vacation in Cancun, Mexico, gets cut short when a shark attacks her close to shore; in Tennessee, a timber rattlesnake bites firefighter Kyle Watson while he hikes in the woods with his family.

High up on an ice-covered Canadian mountain in the middle of the night, a grizzly bear charges professional climber Greg Boswell; in upstate New York, a rabid coyote attacks a retired nurse.

Twenty miles into a marathon in a remote part of New Mexico, Karen Williams finds herself caught between a bear and her cub; Steve Campbell is working on an oil pipeline in Alberta, Canada, when a mountain lion attacks him.

On Christmas Eve, Matt Chenhall is walking with his two young daughters when he is attacked by a kangaroo; Lauren Fagen is volunteering at an animal sanctuary in South Africa when a lion reaches under a gate and pulls her legs through the bars.

While hiking in Alaska, Catherine Dwinnell encounters a 1,000-pound moose that strikes her from behind; in Hawaii, Tony Lee swims a half-mile from shore when something grabs him and drags him below the surface.

In a cozy home of Himalayans, a shy kitten named Hugo follows in his father's footsteps; a rags to riches rescue mix brings her brood of puppies to their new dream home and only girl, Honey, makes an unlikely friend.

Twin dachshund pups, Lulu and Betty, discover their different personalities with a little bit of guidance from their free spirit father; a show pup in training, Chinese Crested Dotty, forms an unlikely friendship with rescue pit bull Bryan.

A cat-loving rescue dog named Sweet Potato welcomes a pair of rescue kittens into their new foster home.

Chip, a golden retriever puppy, tries to be the center of attention; a Great Dane's long legs make the dog a tad clumsy.

The Australia Zoo's alligator snapping turtles need a health check, and it's Robert's job to protect from their fierce bites; Terri and Bindi welcome seven new lemurs from the United States; the Rescue Unit must save possums caught in a chimney.

Problems with nuisance alligators keep the boys busy; a boy encounters a danger in his pool; Ashley's PR scheme involves Scott dressing in a gator costume.

The boys deal with more nuisance alligators; Tre embarks on a mission to locate a legendary creature that supposedly haunts the bayous of Mississippi.

A woman was forced to move out of her home due to her two cats who aggressively attack each other; a daughter feels threatened by her feral cat and fears that her 95-year-old mother may be her next target.

A couple's show cat named Snickers has become tormented by the lifestyle and is aggressive towards the judges; Dexter's constant meowing has put his owner over the edge and is desperate for a resolution.

Issues with the local community and government convince Tia to move the Villalobos Rescue Center from California to New Orleans.

Tia travels to Nashville with Tania and new parolee Randy to save a dog from death row; a storm threatens to flood Villalobos; a rescued puppy may find a permanent home.

A heard of goats stand in the way of Pete building an elegant English retreat with a luxurious hanging bed on an idyllic farm in Waxhaw, N.C.

Inspired by South American treehouse maestro Richard Brunnelli, Pete builds a hexagonal live-in treehouse for a Treehouse Workshop graduate in coastal Oregon.

Pete builds a clubhouse for a camp for children battling cancer; a crow's nest outpost and peek-a-boo roof for full interaction with nature.

Pete and the crew round-up the magnificent seven of cypresses alongside the Frio River and moseys on down to Leakey, Texas to build a gigantic, Texas-sized treehouse with the longest bridge in NT&S history.

A magical castle treehouse to inspire artistic endeavors; partying is the task for Pete and his crew in eastern Nebraska.

Pete builds a Scottish-inspired treetop cottage for Scottish gardeners in Tulsa, Okla., that connects to the clients' home by way of a sky bridge.

Pete Nelson uproots an existing treehouse from the family-owned bed & breakfast Treehouse Point to build a custom-made treehouse as a housewarming gift for his daughter, Emily.

Pete and his crew are tasked with building a nature center, 14 feet off the ground at 10,000-acre nature preserve, Dogwood Canyon in Lampe, Missouri, established by Bass Pro Shops founder Johnny Morris, for the company's upcoming Christmas party.

Pete finds inspiration in old tales to build a mesmerizing treehouse, with a curved turret that soars two stories high and a deck to take in the amazing sights, over the stems of a twisty silver maple on the shore of Lake Chelan.

Pete builds a Scottish-inspired treetop cottage for Scottish gardeners in Tulsa, Okla., that connects to the clients' home by way of a sky bridge.

Pete Nelson uproots an existing treehouse from the family-owned bed & breakfast Treehouse Point to build a custom-made treehouse as a housewarming gift for his daughter, Emily.

Pete and his crew are tasked with building a nature center, 14 feet off the ground at 10,000-acre nature preserve, Dogwood Canyon in Lampe, Missouri, established by Bass Pro Shops founder Johnny Morris, for the company's upcoming Christmas party.

Pete finds inspiration in old tales to build a mesmerizing treehouse, with a curved turret that soars two stories high and a deck to take in the amazing sights, over the stems of a twisty silver maple on the shore of Lake Chelan.

Inspired by South American treehouse maestro Richard Brunnelli, Pete builds a hexagonal live-in treehouse for a Treehouse Workshop graduate in coastal Oregon.

Pete builds a clubhouse for a camp for children battling cancer; a crow's nest outpost and peek-a-boo roof for full interaction with nature.

In 2001, a mysterious half-human, half-animal hybrid bounds across rooftops of New Delhi, running down residents and brutally attacking them; Mungo's investigation attempts to uncover the truth of the Monkey-Man.

A merciless predator known as the Genali that prowls the waterways of Borneo, hunting and killing children, could actually be a reticulated python, a crocodile, or even a deadly dragon.

Jackson and Zoe meet Marti, the owner of a new puppy that harasses her cat; a newly-engaged couple are at their wit's end as they try to blend their fur families.

Juli and her son must overcome the fear of their protection dog; experts encounter an overweight cat bullying a dog.

Jackson and Zoe meet a married couple whose dog attacked their Maine Coon kitten and has not been allowed inside since; the experts also encounter a stubborn client who insists her cats are inventing medical symptoms for attention.

Following surgery, Olga the ostrich is prepared to be reunited with her flock; a squirrel monkey arrives at the zoo; everyone's favorite warthog is back.

A new male okapi named Magani is paired with breeding veteran Kweli who has already had several calves, but Kweli develops congestive heart failure.

A keel-billed toucan confiscated from smugglers begins a new life at the zoo; Troody the young red kangaroo has big shoes to fill; a herd of Bactrian fawns prepares to go on exhibit; the gorillas enjoy a new form of entertainment.

The zoo's lone kangaroo is getting a mate, and the staff is hopeful for a new generation; after months of quarantine, it's moving day for a pair of Mang Mountain pit vipers, and African spoonbill chick Sterling shares a special bond with his keeper.

The zoo welcomes Edward the bat-eared fox as its newest ambassador animal; Amani the aardvark undergoes dental surgery, and the pelican flock gets a new winter home; a snow day means playtime for the animals and hard work for the zoo staff.

Rescued harbor seal pup Sydney finds a new family at the New York Aquarium; zoo staff are challenged when a skittish Amur tiger struggles to adjust to its new home.

At the zoo and the New York Aquarium, bull sea lions Clyde and Tacoma trade places to meet a new set of girlfriends; Sifaka lemurs Gemina and Andri form a new breeding pair to help their species.

An owner drives nine hours to the clinic hoping Dr. Jeff can save her dog's leg; Jeff and his team head to a wildlife sanctuary to treat a pack of wolves; when a kitten with a deformed leg needs treatment, Dr. Baier steps up to the plate.

Dr. Jeff must act fast to save a bulldog after a life-threatening accident; when devastating floods hit Louisiana, Dr. Jeff sends vet tech Hector to rescue pets left homeless in the disaster; Dr. Don operates on a cat with a bad habit.

A boxer kicked in the head by a horse requires urgent surgery to repair its skull; Dr. Jeff helps a woman with a rapidly expanding feral cat colony in her backyard; Dr. Baier preps for delicate surgery on a beloved ferret with a facial growth.

Two sisters rush their tiny dog to the clinic with a life-threatening brain injury; a dog with a broken jaw perplexes Dr. Jeff; a fearless cat with a broken leg wins the admiration of the clinic staff; the team treats some uncooperative yaks.

Dr. Dee hosts a pet tricks competition to raise funds for a no-kill animal shelter in Fairbanks; surgery for a pot-bellied pig named Lilly Lou is full of surprises; stallion of Dr. Dee's long-time friend has a possibly deadly tumor.

Dr. Dee puts her mother on a plane to a remote vet clinic in Manley Hot Springs; Rottweiler could have bone cancer; bunny suffers with large abscess; St. Bernard puppies stop by for a visit.

A boxer kicked in the head by a horse requires urgent surgery to repair its skull; Dr. Jeff helps a woman with a rapidly expanding feral cat colony in her backyard; Dr. Baier preps for delicate surgery on a beloved ferret with a facial growth.

Two sisters rush their tiny dog to the clinic with a life-threatening brain injury; a dog with a broken jaw perplexes Dr. Jeff; a fearless cat with a broken leg wins the admiration of the clinic staff; the team treats some uncooperative yaks.

Dr. Dee hosts a pet tricks competition to raise funds for a no-kill animal shelter in Fairbanks; surgery for a pot-bellied pig named Lilly Lou is full of surprises; stallion of Dr. Dee's long-time friend has a possibly deadly tumor.

Dr. Dee puts her mother on a plane to a remote vet clinic in Manley Hot Springs; Rottweiler could have bone cancer; bunny suffers with large abscess; St. Bernard puppies stop by for a visit.

Rescued harbor seal pup Sydney finds a new family at the New York Aquarium; zoo staff are challenged when a skittish Amur tiger struggles to adjust to its new home.