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All Seasons

Season 1

  • S01E01 Super Grouper

    • January 27, 2009
    • PBS

    At a time when large fish are rapidly disappearing from the world's oceans, one giant is making a comeback in Florida - the Goliath Grouper.

  • S01E02 Mission to Inner Space

    • February 3, 2009
    • PBS

    NOAA’s Aquarius Reef Base is the only undersea research station operating in the world today where aquanauts carry out missions while living and working on the seafloor.

  • S01E03 Corals of the Deep

    • June 23, 2009
    • PBS

    In the deep waters off Florida’s Atlantic coast grow magnificent structures, capable of reaching 300 feet in height. These are the corals of the deep sea.

  • S01E04 Farming the Sea

    • June 30, 2009
    • PBS

    An ever-growing demand for fresh seafood has pushed wild stocks around the world to the brink. Aquaculture is one alternative to wild-caught fish.

Season 2

  • S02E01 No Fish Left Uncounted

    • June 1, 2010
    • PBS

    How do you count two fish, three fish or even a school of fish? In Dry Tortugas National Park, located 70 miles from Key West, Florida, a group of scientists have joined forces to conduct a massive fish census.

  • S02E02 Sentinels of the Seas

    • June 8, 2010
    • PBS

    Bottlenose dolphins are a beloved Florida icon, but recent studies show disturbing signs of immune system dysfunction and disease plaguing this charismatic mammal.

  • S02E03 Seagrasses and Mangroves

    • June 15, 2010
    • PBS

    They are an ancient species of flowering plants that grow submerged in all of the world’s oceans. Seagrasses link offshore coral reefs with coastal mangrove forests. Today, these prairies of the sea, along with mangroves, are declining globally. Scientists fear the diminishing vegetation could result in an ecosystem collapse from the bottom of the food chain all the way to the top.

  • S02E04 Sinking the Vandenberg

    • June 22, 2010
    • PBS

    Off Key West, in the Florida Keys National Marine Sanctuary, lies the world's second largest intentionally sunk shipwreck, the USNS General Hoyt S. Vandenberg. This artificial reef is now attracting fish, fishermen and divers.

Season 3

  • S03E01 Alien Invaders

    • June 7, 2011
    • PBS

    In the waters of the western Atlantic and Caribbean, a voracious alien predator has taken hold. Native to the Indo-Pacific, the invasive lionfish is a major threat to biodiversity and the health of already stressed coral reef ecosystems.

  • S03E02 Reef Revival

    • June 14, 2011
    • PBS

    In the emerging science of coral reef restoration, marine biologists and resource managers are discovering naturally occurring mechanisms that promote coral growth and restore ecological balance in these gardens of the sea.

  • S03E03 Prescription Oceans

    • June 21, 2011
    • PBS

    The oceans are part of America’s newest medical frontier. In Florida, scientists are studying a variety of marine invertebrates which may hold the key to unlocking the secrets of our own biology.

  • S03E04 After the Spill

    • June 28, 2011
    • PBS

    The catastrophic oil spill in the Gulf of Mexico in April 2010 may no longer make headline news, but the story is far from over. Oceanographers continue to study the long-term effects this disaster might have on marine ecosystems.

Season 4

  • S04E01 Tracking Tigers

    • June 6, 2012
    • PBS

    Tiger sharks are the ultimate apex predator. Scientists use satellite tags and DNA forensic tools to better understand the migrations of this magnificent species and to investigate the impacts of the world shark fin trade.

  • S04E02 Mysterious Microbes

    • June 13, 2012
    • PBS

    On coral reefs, microorganisms are copious creatures. Throughout Florida, scientists painstakingly work to identify key players within this microbial community and directly link a devastating coral disease to a human pathogen.

  • S04E03 Grouper Moon

    • June 20, 2012
    • PBS

    During the winter full moons, Nassau Grouper gather in large numbers to spawn. Most of the known spawning sites have been fished out, but the Cayman Islands are home to the last great reproductive population of this endangered species.

  • S04E04 Coastal Carnivores

    • June 27, 2012
    • PBS

    Scientists studying the coastal Everglades have made some perplexing discoveries. Bull sharks are living upstream where alligators should thrive, and gators are swimming out to the ocean to feed. A coproduction with Symbio Studios.

Season 5

  • S05E01 Coral Hybrids

    • June 19, 2013
    • PBS

    Once a common sight in the Caribbean and Florida, Elkhorn and Staghorn corals are now listed as threatened on the U.S. Endangered Species list. But while these corals have declined in recent years, their hybrid appears to be increasing in parts of the region.

  • S05E02 Sunken Stories

    • June 19, 2013
    • PBS

    The oceans are a graveyard of man’s seafaring adventures. Today, underwater archaeologists are scouring the seafloor for clues to our maritime past.

  • S05E03 Creatures of the Deep

    • June 26, 2013
    • PBS

    In the cold, deep waters of the Gulf of Mexico, little-known animals spend their entire lives in near darkness, far removed from our human world. Until now, little research has been conducted on these creatures of the deep, keeping much of their lives a mystery.

  • S05E04 Reefs of Rangiroa

    • June 26, 2013
    • PBS

    Scientists with the Global Reef Expedition are on a six-year mission to study remote coral reefs around the world. Organized by the Khaled bin Sultan Living Oceans Foundation, the expedition kicked off in 2011, with plans to conduct research in the Atlantic, Pacific and Indian Oceans. A coproduction with the Khaled bin Sultan Living Oceans Foundation.

Season 6

  • S06E01 Living Fossils

    • June 18, 2014
    • PBS

    In the deep, dark waters off the coast of Roatan, Honduras, strange flowerlike animals flourish. These sea lilies and feather stars, known as Crinoids, have been around in various forms since before the age of dinosaurs.

  • S06E02 Biggest Fish in the Sea

    • June 18, 2014
    • PBS

    Each summer, the world’s largest known aggregation of whale sharks occurs just off the coast of Cancun, Mexico. Hundreds of these gentle giants come to the area to feed on plankton, giving experts the opportunity to learn more about the largest fish in the sea.

  • S06E03 Galápagos: Windows into the Future

    • June 25, 2014
    • PBS

    The unique oceanic conditions of the Galápagos Islands serve as a perfect natural laboratory to study how climate change may impact corals in the future. A coproduction with the Khaled bin Sultan Living Oceans Foundation.

  • S06E04 Saving Sawfish

    • June 25, 2014
    • PBS

    Strange and prehistoric-looking, Smalltooth Sawfish were once coveted by anglers as popular trophy fish. But habitat loss and overfishing have greatly reduced the animals’ range and landed them on the endangered species list in 2003.

Season 7

  • S07E01 Sea Turtles: The Lost Years

    • June 17, 2015
    • PBS

    After sea turtle hatchlings emerge from their nests, they vanish into the sea. Until recently, their journey was largely shrouded in mystery. Now, as technology advances, researchers are beginning to understand where turtles go during their so-called “lost years.”

  • S07E02 Grand Cayman’s Famous Stingrays

    • June 17, 2015
    • PBS

    Each year, thousands of tourists interact with the tame southern stingrays that congregate in the shallow waters of Grand Cayman’s North Sound. Famous marine artist and scientist Dr. Guy Harvey has assembled a research team to study what impact the ecotourism might have on the wild fish.

  • S07E03 Billfish: Battle on the Line?

    • June 24, 2015
    • PBS

    The unique oceanographic conditions of the eastern tropical Pacific make the area one of the best spots in the world for big game anglers to hook billfish. But intense pressures from commercial fishing operations have taken their toll on the numbers of sailfish and marlin in the region. Researchers are studying the animals to provide the data necessary to protect populations from further decline.

  • S07E04 The Secret Sex Life of Fish

    • June 24, 2015
    • PBS

    Most people are familiar with the pretty tropical fish found in aquariums, but few realize that some of these animals are capable of changing sex. Discover the unique ways of how some fish species do this and why they likely evolved this way.

Season 8

  • S08E01 Sponges: Oldest Creatures in the Sea?

    • June 22, 2016
    • PBS

    Until recently there was scientific consensus that sponges were the first animals to branch off the “Animal Tree of Life,” a kind of family tree for all living and extinct animals on earth. But recent DNA research has cast doubt on that theory, with some scientists suggesting that ctenophores, also known as comb jellies, are an older lineage.

  • S08E02 Manatees: Conserving a Marine Mammal

    • June 22, 2016
    • PBS

    Every winter, hundreds of manatees aggregate near Crystal River, Florida, attracted by the warmer, clear waters. This sanctuary is also a treasure for scientists, who take advantage of these manatee gatherings to study them. From decades of visual ID studies to the most cutting-edge DNA research, experts hope that science will help conserve this beloved marine mammal.

  • S08E03 Maug’s Caldera: A Natural Laboratory

    • June 28, 2016
    • PBS

    In the remote Pacific, the Maug Islands rise out of the sea. Formed by an ancient volcano, shallow hydrothermal vents are found close to corals here. These vents emit levels of CO2 that can be expected in the world’s oceans by the end of the century, making these waters a natural lab for scientists studying the impacts of ocean acidification on coral reefs. A coproduction with Open Boat Films.

  • S08E04 Beneath the Bridge

    • June 28, 2016
    • PBS

    The Blue Heron Bridge in Riviera Beach, Florida, is known as one of the best shore dives in the United States. What appears as an unlikely dive site at first is home to a rich variety of marine life, ranging from tiny nudibranchs to manta rays. Underwater photographers are documenting what lives beneath the bridge, and a scientist is studying how two species of octopus co-exist there.

Season 9

  • S09E01 The Future of Seafood

    • June 21, 2017
    • PBS

    It is estimated there will be two billion more people on the planet by mid-century. To feed this booming world population, more fish will need to be farmed than ever before. One way to increase fish production in a sustainable way is to move aquaculture operations offshore – where there is plenty of available space and strong currents flush out the pens to avoid polluting sensitive ecosystems.

  • S09E02 Toxic Algae: Complex Sources and Solutions

    • June 21, 2017
    • PBS

    Water releases from Lake Okeechobee periodically create putrid mats of blue green algae. Scientists think water pollution is to blame, and if something isn’t done about it there could be irreparable damage to the environment, the local economy and people’s health.

  • S09E03 The Fate of Carbon

    • June 28, 2017
    • PBS

    For millennia, the exchange of CO2 between the oceans and atmosphere has been in balance. Now, with more anthropogenic carbon dioxide in the atmosphere, the oceans are taking up more CO2 as well. This additional CO2 is negatively impacting sensitive ecosystems and scientists worry how changes to the ocean environment will affect the way carbon is cycled through the seas.

  • S09E04 Majestic Mantas

    • June 28, 2017
    • PBS

    Mexico’s remote Revillagigedo Archipelago is a hotspot for oceanic mantas. Scientists are studying the local population using photo ID techniques and acoustic tags which track the movements of these mysterious fish. They are also conducting experiments to see if the filter-feeding rays are impacted negatively by microplastics, tiny pieces of toxic trash that float in the ocean.

Season 10

  • S10E01 Dolphins: Breaking the Code

    • June 19, 2018
    • PBS

    Dr. Denise Herzing has dedicated her career to studying the wild Atlantic spotted dolphins that live in the shallow waters of the Bahamas. Through non-invasive observation, she researches the animals’ social structure, behaviors and communication. Now modern technology is making it possible to correlate the dolphins’ sounds and behavior, bringing experts closer to decoding dolphin communication.

  • S10E02 Cryptic Critters

    • June 19, 2018
    • PBS

    Right under the noses of thousands of scuba divers, a potential new threat appeared on the Vandenberg wreck. It is not surprising that it went unnoticed, since it is the width of a pencil eraser, barely the length of your finger, and perfectly camouflaged. Thankfully, one expert spotted it and immediately knew it didn’t belong. It turns out it was a new species: the Vandy worm-snail.

  • S10E03 Lords of the Wetlands

    • June 27, 2018
    • PBS

    While American crocodiles are recovering in parts of their range, their future looks bleak in Jamaica. Habitat loss and poaching for meat have led to a drastic decline in the population. Dedicated scientists and conservationists are working to save the species through research, education, and conservation initiatives.

  • S10E04 Fishing the Flats for Science

    • June 27, 2018
    • PBS

    Flats fishing is popular with recreational anglers in the Caribbean and the Florida Keys. But until recently, little was known about tarpon, bonefish and permit – the species most coveted by sports fishermen. Now scientists are studying the fish to better understand their movements, habitat, and spawning behaviors.

Season 11

  • S11E01 The Cordell Bank: A National Treasure

    • June 18, 2019
    • PBS

    California’s north-central coast is famous for its natural splendor. Only fifty miles northwest of San Francisco’s Golden Gate Bridge lies the Cordell Bank, a magical underwater island few people have ever heard of. Protected inside a National Marine Sanctuary, this oasis is an ecological hot spot for marine life - attracting birds, sea turtles and marine mammals from thousands of miles away.

  • S11E02 Toxic Waters

    • June 18, 2019
    • PBS

    Harmful algal blooms come in many forms, from toxic outbreaks impacting the health of animals and humans, to non-toxic but expansive sargassum mats devastating local economies and tourism. Scientists are working to understand what causes these blooms, how they impact us, and how we can stop them.

  • S11E03 Corals in Crisis

    • June 24, 2019
    • PBS

    Stony Coral Tissue Loss Disease is devastating Florida’s fragile coral reef ecosystem. But all hope is not lost. Dedicated scientists are working hard to find the cause of the disease, treat the ill and restore these cities of the sea to their former glory.

  • S11E04 Mystery of the Humpback Whale Song

    • June 24, 2019
    • PBS

    Each winter, a population of humpback whales migrates to its breeding grounds in the Hawaiian Islands. It is here that male humpbacks perform their elaborate and haunting song. Experts are studying the purpose of this song and what it might tell them about the animals’ overall fitness.

Season 12

  • S12E01 Florida’s Blue Holes: Oases in the Sea

    • June 18, 2020
    • PBS

    Blue holes scattered throughout the Gulf of Mexico inspire a team of exploration scientists and divers who set out to uncover the mysteries of what makes them ecological oases.

  • S12E02 A Decade After Deepwater

    • June 18, 2020
    • PBS

    Ten years after the Deepwater Horizon oil rig disaster, scientists are still studying its devastating impacts on the Gulf of Mexico. Now they are using lessons learned to prepare for the next big spill.

  • S12E03 Peru’s Desert Penguins

    • June 25, 2020
    • PBS

    Along Peru’s barren coastline seabirds reign. Among them is the adorable Humboldt penguin, which builds its nests in the guano of other birds. Scientists monitor local penguin populations and study the animals’ interactions with fisheries.

  • S12E04 American Samoa's Resilient Coral Reefs

    • June 30, 2020
    • PBS

    American Samoa is home to some of the largest corals on record. Reefs in this remote island paradise are thriving, while corals elsewhere are in serious decline. Scientists study what makes these corals more resilient than others in the wake of local and global stressors.

Season 13

Season 14