Oiled Kemp’s Ridley turtle.

Affected Gulf Resources

Oil released during the Deepwater Horizon disaster injured plants, wildlife, and entire ecosystems. The oil posed a widespread threat from the deepest reaches of the Gulf to its shorelines. Both private and public lands were adversely affected, including critically important national and state wildlife refuges and parks, and national estuarine reserves.

Much of the released oil rose through the water column to the surface, encountering marine life on the way. At the water’s surface, the oil and dispersants spread out in a layer of contaminants that moved slowly towards the Gulf coast. Many kinds of fish and wildlife were exposed to this floating oil, not only during the spill, but for some time after the spill ended. Much of the floating oil made it to barrier islands and shorelines, where it affected wildlife, people and the way people traditionally enjoyed the Gulf’s resources for recreational and other activities.

Read more below about which wildlife and habitats were likely affected by the spill, and how they were affected.

Habitat in the Affected Area

Wildlife depends on clean, healthy habitat for food, shelter and reproduction. These important areas were affected by oiling, which led to habitat degradation and loss, decreased food abundance, and physical disturbance of the habitat.

Deep Sea Habitat

Deep sea habitats such as bottom sediments and coral reefs are important to bottom-dwelling organisms—such as plankton, forage fish, and invertebrates—that are the base of the food chain. The soft sediments and sporadic coral outcroppings at this depth are home to tube worms, bacteria, jellyfish, fish, and corals.

Sperm whales are known to dive to these depths to feed on squid, skate, fish, and sharks. This environment is quite inhospitable—temperatures are near freezing, pressure is high, and there is no sunlight. Oil, drilling mud, and dispersants were released in the vicinity of the well head, threatening these organisms.

Water Column Habitat

The water column serves as important habitat for many species. Plankton, jellyfish, fish, marine mammals, and many other organisms live in or use the water column to feed, migrate, seek shelter, and reproduce.

Much of the oil released from the Deepwater Horizon wellhead traveled up through the water column, where some of it dissolved, impacting organisms living there. Even organisms that don’t live in or on the water, such as diving birds, can be injured by a contaminated water column.

Water Surface and Sargassum Mats

The vast surface waters of the Gulf of Mexico support a wide variety of wildlife. When oil reached the water surface, emergency response workers and researchers observed oil on the surface of Gulf waters directly impacting dolphins, sperm whales, whale sharks, birds, and sea turtles.

Floating oil also affected an important plant species: Sargassum, a brown alga that forms large floating mats in the Gulf of Mexico. These mats support marine fish, invertebrates, sea turtles, and other living things, and contamination of the mats brought many organisms into direct contact with oil.

Near Shore Habitat

Oyster reefs, seagrass beds, beaches, tidal mud flats, mangroves, marshes and wetlands are all habitat found on or near the shoreline. And, they were all degraded by oil and disturbed by response and cleanup activities.

Oil released by the spill severely affected the edges of marshes, where it persisted for long periods. Sediments in these areas appeared to be more heavily oiled than those farther from shore. Once on marsh shorelines, the oil impacted not only marine organisms that depend on these habitats for feeding and nursery areas, but also posed a threat to marsh and shore birds and terrestrial wildlife.

Wildlife of the Affected Area

Wildlife in the Gulf might come into contact with the oil by swimming through the oil (or dispersants), ingesting it, or inhaling it at the surface. These exposures can cause a variety of health impacts, including death.

Fish and Shellfish

Species with essential fish habitat potentially affected by the oil spill include scalloped hammerhead, shortfin mako, silky, whale, bigeye thresher, longfin mako, and oceanic whitetip sharks; swordfish, white marlin, blue marlin, yellowfin tuna, bluefin tuna, longbill spearfish, and sailfish.

Other fish that use areas of the Gulf where oil was observed include red snapper, grouper, gray triggerfish, red drum, vermilion snapper, greater amberjack, black drum, cobia and dolphin (mahi-mahi), coastal migratory open water species such as king and Spanish mackerel, and open water sharks.

Shellfish in the Gulf potentially affected by the oil spill include oysters, scallops, and several species of shrimp and crabs.

Marine Mammals

There are many kinds of mammals known to live in the Gulf of Mexico. These animals include 12 species of whales, 9 types of dolphins and the Florida manatee. Under the Endangered Species Act, six of the whale species and the manatee are listed as endangered.


Five species of threatened/endangered sea turtles (Kemp’s ridley, green, hawksbill, leatherback, and loggerhead) are residents of the Gulf of Mexico.

The most important nesting beaches in the world for Kemp’s ridley turtles are in Texas and Mexico.

The Gulf of Mexico waters off the southeastern coast of Louisiana include some of the Gulf’s most important habitat and foraging areas for many of these turtles.


Marshes in the Gulf of Mexico provide extremely important feeding and nesting habitat for several bird species, such as shearwaters, northern gannets, and frigates. Royal Terns and Gulls.

Bird species of particular concern include marsh birds: brown pelicans, diving ducks, wading birds, piping plovers (a threatened species).

Specifically, barrier islands off the southeastern coasts of Louisiana provide critically important nesting habitat for many birds of the Gulf coast, including the brown pelican.