Season Three

Jonathan visits the Georgia Aquarium in Atlanta—the largest aquarium in the world—where they keep not one but four whale sharks in captivity, as well as two manta rays. Whale sharks are the largest fish on Earth and Jonathan learns how these animals are maintained in captivity while he dives with them in a 6 million gallon fish tank!

Jonathan travels to Andros, an island in the Bahamas, to investigate underwater caves that start in blue holes. A blue hole looks like a pond, but leads into a vast underwater cave system. In the Bahamas, these caves often lead to the ocean. As Jonathan explores the ocean end of the caves, he learns how the two systems are connected.

The Goliath Grouper is one of the largest bony fish in the world, and this made it the target of intense fishing efforts for many years. After nearly becoming extinct, the fish was afforded legal protection enacted in 1990. Twenty years later, the protection is finally starting to pay off. Jonathan joins famous National Geographic photographer David Doubilet as he visits a shipwreck in Florida where Goliath Groupers gather to spawn every year, and meets dozens of these massive animals!

Jonathan visits the largest reef system in the world: the famous Great Barrier Reef of Australia. In addition to going diving, he visits the reef as non-divers often do—by submarine, helicopter and even in a bubble helmet! Along the way he meets some amazing animals such as a friendly sea turtle and a giant wrasse!

Jonathan explores how animals in the ocean use color, not just for camouflage but also to stand out!

In 2009, a lone pilot whale was stranded on a Curaçao beach. Fortunately, he was rescued by the staff of the Curaçao Sea Aquarium. They named him Sully and spent months nursing him back to health. After being successfully rehabilitated, Sully refused to go back to the wild and was adopted by Sea World San Diego. Jonathan learns what was wrong with Sully and what had to be done to save him.

Jonathan explores cleaning stations on the reef, where animals get cleaned of parasites and infection by other animals. Some examples shown are anemones and anemonefish (clownfish), wrasses, shrimp, manta rays, moray eels, Goliath groupers, sea turtles and barracuda. This episode was filmed in many locations such as Malaysia, the Philippines, Yap, Australia's Great Barrier Reef and the Caribbean.

In this intriguing segment, Jonathan goes diving with a group of playful sea lions in the Galapagos Islands. Impressed by the apparent inquisitiveness of the sea lions, Jonathan heads to the Mystic Aquarium in Connecticut where he learns how they train sea lions, and how smart they are. Jonathan finds out that the sea lions at Mystic know more than 100 commands, and he gets a lesson in sea lion training!

Every year, Humpback whales in the North Atlantic make a long migration down to the Caribbean to have their calves in warm, calm water. Many of these whales go to one particular area called the Silver Banks near the Dominican Republic. Jonathan spends a week in the Silver Banks filming whales underwater, and you won't believe how close he gets to the whales, and the exceptional behaviors he observes!

Jake is a 13 year-old fan of Jonathan Bird's Blue World. Jake wrote an essay for school about his dream to dive with Jonathan, and the Blue World team is making it come true. The segment begins when Jonathan and his film crew make a surprise visit to Jake's house. Their mission? To get him certified to dive so he can go on a dive adventure with Jonathan. The segment concludes with Jonathan and Jake exploring the underwater world of Grand Cayman Island together!

Jonathan visits the Curaçao Sea Aquarium to learn about their dolphin program from George Kieffer, the head dolphin trainer. After taking George's dolphin class, he joins him on a dive with Annie, one of the dolphins that is trained to swim with divers on the reef outside the resort. Why don't the dolphins swim away? That's what Jonathan finds out!

Many people don't realize that there are snakes that live in the ocean. And believe it or not, they're actually considerably more venomous than land snakes! Jonathan travels to Australia and the Philippines to find these marine reptiles, and learns why they are almost completely harmless to divers.

Jonathan explores different types of symbiosis in the ocean, including mutualism, commensalism and parasitism, and how animals use it for survival.

How does an animal like coral that lives attached to the bottom (and can't move around) create new colonies far away? Jonathan spends a week in Bonaire studying coral spawning. He learns how these animals release eggs into the water at the right time of the year to create new coral colonies. But they only do it at night, at certain times of the year. Jonathan's film expedition requires careful timing.

In the Yucatan jungle of Mexico, Jonathan explores Muyal-Ha sinkhole (cenote), which is over 100 feet deep and has a false bottom created by clouds of hydrogen sulfide. It’s an incredibly eerie place! A cenote is a deep "pond" created when the roof of a flooded cave collapses exposing the water below.

Jonathan explores how animals in the ocean defend themselves using venom, spines, teeth, speed, maneuverability, ink and even a squirt gun!

Jonathan explores the basic biology of sharks and what makes them different from bony fish including buoyancy, respiration, coloration, etc.

Deep underground, in caves, there is no light. Because there is no light, there is almost nothing for animals to eat. Yet life survives here. The top predator in these sunless ecosystems is a tiny blind cavefish, only a few inches long. These fish are extremely rare, only found in the dark recesses of caves. Jonathan joins Christine Loew, a veteran cave explorer, on a mission to film this elusive fish in Mexico's Riviera Maya.

Jonathan examines the biology of coral reefs and their importance to the marine ecosystem.

When most people think of a shark, they think of an animal like the Great White or a reef shark. But there are hundreds of small, bottom-dwelling sharks like the Wobbegong that blend in to the bottom to hunt as ambush predators, the Indonesian Walking shark that walks on its fins, or sharks like Nurse sharks that simply spend most of their time resting on the bottom. Jonathan travels from Australia to Indonesia looking at interesting sharks that don't look like sharks!

Jonathan heads down to Cancun in Mexico on an expedition to film one of the world's fastest fish—the sailfish! He gets in the water with a school of sailfish zooming around hunting sardines. In addition to having huge dorsal fins giving them their name, the sailfish also have long pointy bills like spears they use to catch their prey. Jonathan dodges the bills while filming the action!

In Bar Harbor, Maine, Jonathan spends a day diving with his friend Diver Ed on his boat the Starfish Enterprise. Diver Ed and his wife Captain Evil take people on a virtual dive called the Dive-In Theater with a video camera attached by a long cable to a TV monitor on his boat. Their ocean explorations are famous around New England, and when Jonathan joins the crew for a day, the guests are in for a good time!

Jonathan goes to a cleaning station to watch a Potato Grouper (also called a Potato Cod) get it's nose picked by a cleaner wrasse! Then he tries to get cleaned himself!