Octocorals are common in deep-sea environments. Corals are really a collection of tiny creatures called polyps — these polyps each bear eight tentacles and share a stomach, giving the octocoral its name.
These octocorals provide a habitat for squat lobsters, a deep water lobster species. Here's another example of a coral, with a different species of squat lobster using it as a safe haven. Like their shallow-water brethren, these deep-sea corals are filter feeders, positioning themselves in prime locations to catch plankton. This bubblegum coral attached itself to a vertical rock face over 8, feet below the surface, proving life can thrive under even the most difficult circumstances.
Beyond corals, the scientists caught magnificent photos of some truly bizarre deep sea dwellers, like this cusk eel. The eel hunts by resting in the sediment — it's large eyes help it spot prey swimming above it in the dark.
This lobster is completely blind, spending most of its life in burrows in the sediment. This one was caught outside at around 2, feet down. Skates cruise above the sediment looking for prey. This one has a parasitic isopod — a pill-bug-like creature — attached.
This grumpy looking fish is a goosefish, caught on camera around 2, feet below the surface. The goosefish uses the lures seen between its eyes to help capture its prey. This long-legged shrimp, like the blind lobster, prefers to spend its time in burrows. This one was captured cruising around the sediment at over 9, feet down.
This little guy is a Western roughy, which is one of the longest-living deepwater fish species. The researchers observed some especially weird octopus behavior. These two appear to be wrestling for den space underneath an old shipwreck. The loser, pictured here, attempts to bury beneath the sediment after its defeat. Scientists identified this long, narrow squid as a Echinoteuthis atlantica, a common deep-sea dweller found in the Atlantic.
Among the most bizarre deep sea dwellers are these ctenophores, or jellyfish. This one, found with its tentacles fully extended around 4, feet deep, almost looks like something out of Star Wars. One of the least understood environments in the deep, these brine pools are areas where extremely saline water sinks to the bottom. The brine pools kill the surrounding shellfish.
These tubeworms employ a unique strategy to survive on the seafloor. In the absence of any sunlight, they use bacteria stored within their organs to convert hydrogen sulfide into the sugars and amino acids needed for life. At its deepest point the bottom is 2.
The Gulf is a very accessible body of water. About half of Mexico and one third of Cuba drains into it also. Because of this estuaries tell us a lot about how well we are protecting our water resources. Every day, you and I affect the health of the Gulf ecosystem. Cooking, cleaning, watering the lawn, flushing, and even driving the car can cause water pollution if done without regard to the impact on the environment.
When multiplied by what the millions of us do who live in the river basins that empty into the Gulf, it is easy to understand that how we treat our watersheds affects the health of Gulf ecosystems. The Gulf is one of the most productive waters in the world for aquatic organisms. It provides habitat for many of our most important seafoods. The Gulf is productive in other ways, too. The Gulf is shaped like a giant wide-brimmed bowl filled with saltwater. Starting from the coastline and moving out into the Gulf, the edge is full of wetlands, estuaries , and bays, opening out to wide and shallow shelves that gradually slope into deep waters.
The floor of the Gulf is mostly a vast expanse of soft mud. The freshwaters that flow into the Gulf greatly affect the health and productivity of the aquatic life there. The watershed for the Mississippi River is over six times larger than Texas. It includes 31 states and two Canadian provinces. The natural flow from the Mississippi River has always influenced productivity in the Gulf. Freshwater inflow provides nutrients that are carried by currents throughout the Gulf.
The nutrients promote growth of phytoplankton. These are primary producers that form the base of an extensive food chain including zooplankton , macroinvertebrates , fish, whales, sea turtles, sea birds, and many other forms of marine life. Human activities have added wastes, pollutants , fertilizers, and extra sediments to the flow of the Mississippi River. As long as the Gulf remains healthy it can absorb the impact of some level of nutrients and pollution.
Today, as much as million tons of sediment may flow into the Gulf each year. Extra nutrients have upset the natural balance of aquatic production in Gulf waters adjacent to Louisiana and Texas.
This results in a biomass of primary producers far beyond what would occur naturally, often called an algae bloom. The increase in phytoplankton then affects the Gulf food chain, increasing food for zooplankton and other aquatic life.
But the amount of phytoplankton produced in such a short time is well beyond the capacity of primary consumers to graze it down to a balanced level.
Phytoplankton have a relatively short life span, so much of the phytoplankton dies before it can be consumed. When the phytoplankton organisms die, they sink down to the ocean floor where decomposers , such as bacteria, break them down. At the time of year this usually happens, the water column is stratified, meaning that temperature and salinity differences between surface and bottom water layers prevent the layers from mixing.
This isolates bottom waters from being resupplied with oxygen from the surface. The plankton that has sunk to the bottom is decomposed by bacteria , but large amounts of dissolved oxygen are consumed by the bacteria and the dissolved oxygen is quickly depleted. Organisms capable of swimming away such as fish and shrimp may leave the area, but life that lives in or on the bottom has nowhere else to go. Many species can experience stress or die as a result of this low dissolved oxygen. Hypoxia adversely affects production of seafood and other aquatic life as food webs are disrupted and organisms at all trophic levels are harmed.
Hypoxia can last for several months until the water layers mix, which can happen due to storms or when the surface water cools in fall and winter. The seashore is the first thing many of us see when we visit the Gulf. We may run down the sandy beach to go swimming, go fishing, or just watch as the waves come rolling in.
Texas has the most extensive barrier islands in the Gulf, including Padre Island which is the longest barrier island in the world. It is miles long and protects nearly a third of the Texas coast. Beaches in the western Gulf of Mexico, which is where Texas is located, are considered to be moderate to high energy beaches where there are large waves most of the year. The eastern Gulf is a low energy area, which has smaller waves, on average. This is why the Gulf coast of Texas is a better place for surfing and wind sports, such as windsurfing and kiteboarding, than the Gulf coast of Florida.
Just off the beach, especially in the moderate to high wave energy areas, there are one or more sand bars and troughs getting progressively deeper as you go offshore. Most species here live by burrowing in the shifting sands of the bottom. Beach clams, marine worms, and sand dollars are common in the surf zone. This is where the waves wash back and forth along the beach, also called the swash zone. The beach slopes steeply up to a flat area that generally stays dry. This is called the backshore, and is where people usually walk and lay on beach towels.
This is also the part of the beach where you can find sand crabs and occasionally nesting sea turtles. Sand dunes make up the zone behind the backshore. They vary in height from only a few feet up to the largest in the Gulf at 30 feet on Padre Island. They are usually covered with grasses that help hold the sand in place.
The dunes help protect areas behind the beach from wind and storms. There are many beach parks along the Texas coast. All of these are great places to visit, go fishing, or go surfing.
In addition these parks help protect wildlife and aquatic life. Life in the Gulf is diverse because there are many different ecosystems and habitats that support many kinds of organisms and species.
Even in the deepest and darkest reaches of the Gulf there is life. Chemosynthetic communities are found deep in the Gulf. Along the US portion of the Gulf coast, 33 major river systems and estuaries empty into the sea. The Gulf Stream, which originates in the warm waters of the Gulf of Mexico, is one of the strongest ocean currents in the world. There are 31 major estuarine watersheds in the Gulf of Mexico.
Louisiana is an important area for the millions of migratory birds that fly across the Gulf of Mexico, which includes nearly all of the migratory landbird species of the eastern United States, as well as many western species. Radar technology has shown that hundreds of millions of birds cross the Gulf of Mexico at night during migrations, with as many as 2.
There are 29 marine mammal species found in the Gulf of Mexico, including such icons as bottlenose dolphins, humpback whales, minke whales, sperm whales, and the West Indian manatee. Many of the species of marine mammals found here are threatened or endangered.
The gulf is home to five species of threatened and endangered sea turtles , including Kemp's ridley sea turtles, Hawksbill sea turtles, Green sea turtles, Loggerhead sea turtles and Leatherback sea turtles. As many as 49 shark species are known to inhabit the Gulf of Mexico, including Silky, Bull, Lemon, Oceanic whitetip, Dusky, Tiger, Thresher, several species of hammerhead, and even whale sharks, just to name a few.
As with marine mammals and turtles, may of these once populous species are also threatened, endangered or are species of concern. Isla Holbox was uncovered just a few years ago as a prime place to see whale sharks feeding in large groups during their annual migrations.
The area is now struggling to balance an ecotourism industry with protecting these gentle giants. Sargassum is a widespread genus of seaweed that creates floating oases for marine species, from sea turtles and seahorses to tuna and billfish, and patches can become so large and dense they can be detected from space. Manatees are an iconic figure of Florida's coasts.
They can reach up to 12 feet in length and weigh more than 1, pounds, but only 5, remain in the wild as run-ins with boaters and loss of coastal habitat impact populations.
Brown pelicans have made an incredible comeback after being nearly wiped out by DDT. Sperm whales call the gulf home. Family groups of females and young totaling to 1, individuals reside in the gulf , and when males come to visit, the number can hit as high as 3, Coral reefs grow only in specific ecosystems with the right depth and temperature of water, and the right mix of nutrients and wave action. Reef growth is relatively slow with an individual colony growing between. Black coral living in the Gulf of Mexico is one of the slowest growing deep sea corals, and have been found to be up to 2, years old.
The majority of Florida's sport fish species and other important species spend their lives around coral reefs. Coral reef ecosystems in Florida are extremely diverse, supporting more than 6, species --including types of fish; varieties of starfish, sea urchins, sand dollars and sea cucumbers; 55 species of soft corals; and 63 species of stony corals. Once the most abundant and important coral species in the Caribbean coral reefs, Elkhorn Acropora palmata and staghorn A.
Coral reefs need platforms on which to grow, and creating artificial reefs is a popular tactic to help new coral reefs begin -- attracting not only fish and other animal species but also tourists. Everything from retired ships to oil platforms can be used for creating artificial reefs.
At the end of , 1, platforms were retired from oil and gas production and of the retired platforms were donated and permanently dedicated as Rigs-TO-Reefs for fisheries enhancement.
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