Skip to main content
Access to this video is a benefit for members through PBS Passport.

Up Next

Galapagos: Window into the Future

Galapagos: Window into the Future

Season 6 Episode 603
27:02
Saving Sawfish

Saving Sawfish

Season 6 Episode 604
26:54
Dolphins: Breaking the Code

Dolphins: Breaking the Code

Season 10 Episode 1001
26:43
Cryptic Critters

Cryptic Critters

Season 10 Episode 1002
26:42
Lords of the Wetlands

Lords of the Wetlands

Season 10 Episode 1003
26:42
Fishing the Flats for Science

Fishing the Flats for Science

Season 10 Episode 1004
26:42
The Cordell Bank: A National Treasure

The Cordell Bank: A National Treasure

Season 11 Episode 1101
26:42
Toxic Waters

Toxic Waters

Season 11 Episode 1102
26:47
Corals in Crisis

Corals in Crisis

Season 11 Episode 1103
26:42
Mystery of the Humpback Whale Song

Mystery of the Humpback Whale Song

Season 11 Episode 1104
26:42
Florida’s Blue Holes: Oases in the Sea

Florida’s Blue Holes: Oases in the Sea

Season 12 Episode 1201
26:42
A Decade after Deepwater

A Decade after Deepwater

Season 12 Episode 1202
26:42
Back to Show
Changing Seas

Biggest Fish in the Sea

Season 6 Episode 602

Each summer, the world’s largest known aggregation of whale sharks occurs just off the coast of Cancun, Mexico, attracting tourists and scientists alike. 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.

Watch Preview
Support Provided By
Season
Saving Sawfish
Unlock with PBS Passport
26:54
Scientists conduct research to save the Smalltooth Sawfish.
Galapagos: Window into the Future
Unlock with PBS Passport
27:02
Scientists spend a month in the Galapagos Islands to conduct research.
Living Fossils
Unlock with PBS Passport
26:48
Discover Crinoids which have been around since before the age of Dinosaurs.
Reefs of Rangiroa
Unlock with PBS Passport
26:46
The Changing Seas team meets with researchers in French Polynesia.
Creatures of the Deep
Unlock with PBS Passport
26:46
New research sheds light on the lives of mysterious creatures of the deep.
Sunken Stories
Unlock with PBS Passport
26:45
Divers from around the country learn how to map shipwrecks.
Coral Hybrids
Unlock with PBS Passport
26:45
Follow one scientist studying coral in Belize.
Coastal Carnivores
Unlock with PBS Passport
27:14
Scientists studying the coastal Everglades make some perplexing discoveries.
Grouper Moon
Unlock with PBS Passport
27:01
The Cayman Islands are home to the last great reproductive population of grouper.
Mysterious Microbes
Unlock with PBS Passport
29:33
Scientists work to identify and link a devastating coral disease to a human pathogen.
Tracking Tigers
Unlock with PBS Passport
27:16
Scientists use satellite tags and DNA forensic tools to track tiger sharks.
After the Spill
Unlock with PBS Passport
26:47
Oceanographers continue to study the long term effects of an oil spill.
Active loading indicator