The NOAA Ship Okeanos Explorer conducts operations in the northern Gulf of Mexico. Image Credit: NOAA Okeanos Explorer Program via Flickr // CC BY-SA 2.0

 
As the largest gulf in the world, the Gulf of Mexico has long played a significant role in the economy and ecology of the United States—and beyond. Here are a few things about this impressive body of water you might not have known.

1. IF STRETCHED ACROSS LAND, THE GULF OF MEXICO WOULD SPREAD FROM LOS ANGELES TO NEW YORK.

From the tip of the Yucatan Peninsula in Mexico to the island of Cuba, the Gulf’s shoreline extends for 3500 miles. According to the Harte Research Institute for Gulf of Mexico Studies, the Gulf holds 643 quadrillion gallons of water and reaches a depth of more than 12,000 feet. It contains half of the nation’s coastal wetlands, 90 percent of its seagrass, and all its mangrove habitat.

2. ITS WATERS ARE TEEMING …

An Atlantic spotted dolphin. Image credit: NOAA via WikimediaCommons // Public Domain

This sea boasts incredible biodiversity—scientists have inventoried 15,419 species in the Gulf ecosystem, ranking it in the top five ocean areas globally. Residents include hundreds of species of fish, hundreds more of crustaceans, four species of whales, 28 species of dolphins, five species of sea turtles, and many sharks, including hammerhead, tiger, thrasher, and great white. The Gulf contains one of only two breeding grounds for Atlantic bluefin tuna. It also hosts two large tarpon populations: one that spawns off Mexico's Yucatán peninsula and follows the Texas coast to northern waters and another that spawns offshore near Florida.

3. … BUT LESS SO EVERY DAY.

This rich ecosystem is in trouble; 52 of its species appear on the IUCN Red List of Threatened Species as critically endangered, endangered, or vulnerable. These include Bluefin tuna; whooping cranes; Kemp’s ridley, loggerhead, and green sea turtles; grouper species; blenny species; corals; blue, finback, and sperm whales; and sixteen species of sharks. Because of overfishing and destructive fishing practices, as well as declining water quality—including oil spills, pollution, and debris from coastal development—as well as invasive species and climate change, many species are on the decline.

4. A LOT OF RIVERS RUN INTO IT.


Sediment in the gulf. Image credit: NASA Earth Observatory via Wikimedia Commons // Public Domain

Forty percent of the continental U.S.—the entire landmass between the Appalachian and Rocky Mountains, covering 31 states—drains into these waters. Thirty-three major rivers drain into the Gulf, the largest of which is the Mississippi. That means the Gulf has to handle the agricultural runoff from the Mississippi basin. High levels of nitrogen and phosphorous from fertilizers and oxidized nitrogen from fossil fuel combustion flow from the Mississippi into the waters of the Gulf. These unnaturally high levels of nutrients significantly increase growth of phytoplankton and algae. As these plants die and bacteria feed on them, it uses up oxygen in the water. This process has created an ever-growing hypoxic area, a region where the concentration of dissolved oxygen in the water falls so low that plants and animals die. This "dead zone" grows every summer, and it’s the largest human-caused dead zone in the world. In 2106, it is expected to grow larger than the state of Connecticut.  

5. BUT FOR NOW, EAT UP!


Mario Tama/Getty Images

 

While many fish species are in decline, seafood is still big business here. In 2014, commercial fishers landed 546,478 metric tons of seafood in the Gulf of Mexico, representing a dockside value of more than $989 million. Shrimp accounted for more than half of that. Commercial fishing in the Gulf accounts for a lot of jobs: 26,000 in 2012, with another 6,720 in seafood processing, 11,459 in seafood wholesale businesses, and 59,098 in seafood retail. That’s not to mention casual fishing: Recreational anglers spend around $1.5 billion a year on fishing trips in the Gulf, and about twice that on related equipment like tackle and boat expenses.

6. IT’S NOT JUST PARADISE FOR SEAFOOD CONNOISSEURS.


Thermodynamix via Flickr // CC BY-NC-ND 2.0

The Gulf is just as popular with corals. Caribbean-style coral reefs grow on top of salt domes rising from the floor of the Gulf near the edge of the continental shelf, the northernmost reefs in the U.S. and some of the healthiest in the world. The Flower Garden Banks National Marine Sanctuary, 100 miles off the Texas and Louisiana coasts, protects three of the Gulf’s almost 20 reef areas. Sanctuary scientists monitor these three areas annually as part of a long-term program that began in 1988, making it one of the longest such coral reef research programs anywhere in the world.

7. LARGER CRITTERS LIKE IT TOO.

Whale sharks gather in groups as big as 100 to feed near the mouth of the Mississippi River during the summers. The world’s largest fish, growing up to 50 feet long, whale sharks eat primarily plankton. While they mostly feed at the surface, they can dive 4,500 feet deep. Sharks tagged by Belize-based shark researcher Rachel Graham proved that individual animals travel between Belize, the Yucatan and the northern Gulf of Mexico, an impressive distance. Unfortunately, the International Union for Conservation of Nature Red List ranks this species as endangered. They are targeted for their meat and fins, killed when caught in nets set for other species (especially tuna), and injured or killed by ships.

8. YOU COULD CALL IT AN AQUATIC HIGHWAY.


Baby turtles on the beach in Baldwin County, Alabama. Image Credit: Bureau of Land Management via Flickr // CC BY 2.0

The Nature Conservancy recently analyzed data on 26 species from more than 100 scientists for a report identifying four major migratory pathways—dubbed "blueways"—criss-crossing the Gulf. These routes are used by fish, mammals, sea turtles, and birds, with migrations occurring year-round. But the organization notes that less than one percent of these aquatic corridors, and less than 20 percent of area used as stopovers by migratory birds, are currently protected or managed areas, and few multinational agreements provide protection to migrating species.

9. THE GULF DOESN’T ALWAYS STAY IN THE SEA.

One of the reasons it’s such a popular spot for animals and birds is Sargassum, a gold-colored, floating algae that provides resting, feeding, and breeding areas for many species. The gulf annually produces about a million pounds of the seaweed. It rides on currents from the Gulf to collect in the Sargasso Sea, a 1.5-million-square-mile area in the North Atlantic subtropical gyre. It also circulates onto Gulf beaches, sometimes piling up in significant, stinky quantities. Many communities that depend on tourism clear it from the beach as fast as they can, but scientists discourage this, as Sargassum likely contributes to beach and dune stability (providing increased protection from storms), and provides food for a variety of creatures. Galveston, Texas, recently put up educational signs and handed out fliers asking visitors to be tolerant and recognize the seaweed’s importance. The Galveston Park Board even organized a Bucket Brigade, training volunteers to introduce beach-goers to the interesting creatures living in the seaweed.

10. GULF ENERGY POWERS MUCH OF THE U.S.

Oil production from the Gulf in 2011 accounted for 54 percent of U.S. total, and natural gas production from the region accounted for 47 percent. The area also contains almost half the country's refining capacity. There have been thousands of wells drilled in the Gulf, the first in 1938 in 14 feet of water about a mile from the Louisiana coast. The first offshore well out of sight of land was drilled 10 miles off the coast in 1947. Today, offshore rigs drill in waters deeper than 10,000 feet.

11. WE'RE STILL FIGURING OUT THE LONG-TERM EFFECTS OF REPEATED OIL SPILLS.


Fire boats battle a fire at the offshore oil rig Deepwater Horizon April 21, 2010 in the Gulf of Mexico off the coast of Louisiana. Image Credit: U.S. Coast Guard via Getty Images

 
This oil and gas development can come with a price. The three-month-long Deepwater Horizon oil spill in 2010 poured an estimated 4.9 million barrels of oil (nearly 206 million gallons) and an equivalent volume of gas into the Gulf, with about 1.8 million gallons of chemical dispersants added by BP. It represents the second major spill in the Gulf; the first was Mexico's Ixtoc 1 well in the Bay of Campeche, which blew in June, 1979, spewing 140 million gallons of oil until it was stopped almost a year later. These two Gulf spills are the largest accidental marine oil spills in history, and both occurred due to platform blowout, John W. Tunnell Jr., endowed chair for biodiversity and conservation science at the Harte Research Institute for Gulf of Mexico Studies, tells mental_floss. Tunnell was one of the few scientists who studied the ecological impact of Ixtoc when it happened. Funding for research on its effects quickly dried up, though, which Tunnell calls a missed opportunity—one that became clear after Deepwater Horizon. In 2015, Tunnell received funding for a three-year project to document residual impacts from Ixtoc as part of efforts to predict the long-term impacts of Deepwater Horizon. It's still ongoing.