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.

Footage of humpback whales & whale research taken under the authority of NMFS MMPA/ESA Permit No. 19655.

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.

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.

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.

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.

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.

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.

Deep underwater, on a shipwreck near Key West, lives a tiny potential new threat. Being in the right place at the right time, one expert spotted it and immediately knew that it didn’t belong. Researchers want to know where this new species came from, and whether its sudden appearance spells disaster for the delicate coral reef ecosystem in the Florida Keys.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.”