The Gulf of Mexico cold-seep tube worms can get up to 10 feet long and sometimes live in groups of millions of individuals. The animals in this picture are about 6 feet long and as big around as your finger. Click on the worms for a closer view.

The tubeworms have no mouth, gut or anus. Instead, in the center of their body they have a giant organ called the "trophosome" which is full of symbiotic bacteria.

To live and grow, the tubeworms take up the dissolved gases their symbionts need from the water and transport the chemicals through their blood to their symbionts. The symbiotic bacteria use the hydrogen sulfide for energy and make food for the tube worm from the carbon dioxide (just like the way a plant makes food from sunlight and carbon dioxide).

In the Gulf of Mexico enough sulfide comes out of the sediment to reach the gill-like plumes of the young tubeworms (which stick out of the top of their tubes) as shown in the lower left panel. Our current studies indicate that the adult tubeworms in large "bushes" may take up the sulfide from the sediment using the root-like end of their tubes, as shown in the upper right panel.

We use a new technique to measure the growth of tubeworms. First we stain the tops of the tubes blue using a "stainer" held in the arm of the submarine as shown here. Click on the picture to see how much they can grow in one year.

The new white tube growth can be seen above the previously stained tubes. In one year these worms grow less than one inch. After several years of measurements, we have calculated that the large worms are over 100 years old.

The submarine collects mussels for us to study. We find them in large mussel beds with abundant methane in the bottom water. Click on the mussels for another view.

This community of mussels and tubeworms has a crabby visitor. Click on the crab for view of another mussel community.

With the mussel "on the half shell" you can see all of its body parts. Click on the mussel to identify the parts. Notice especially the very large gills.

This is one of the adductor muscles. They hold the shells together.

This is the mantle. The mantle makes the shell of the mussel and also holds most of the reproductive tissues.

This is one of the mussel's gills. The gills of these mussels are much larger than those of a normal shallow-water mussel. The symbiotic bacteria are found in these gills.

This is the foot. Mussels use their foot to push themselves around when they want to move. They only have one foot and don't move very fast.

These are the byssal threads. Mussels use these to attach themselves to rocks or each other.

This is a laser line scan mosaic of a pool of brine surrounded by mussels at a depth of 700 meters in the Gulf of Mexico. The brine is 4 times as salty as sea water and is supersaturated with dissolved methane gas. Click on the different areas of this mosaic for closer views.

Here in the middle of the mussel bed, we find a solid carpet of mussels of all ages along with visitors like starfish and eels.

We don't find any baby mussels on the outer edge of the mussel ring, however thick white bacterial mats are often present among the adults and empty shells.

Outside of the ring of mussels is the normal muddy ocean bottom with occasional animals like this little eel.

Here is the Johnson Sea Link floating on the pool of brine surrounded by mussels. The brine is so dense that the submarine cannot dive in it, but only floats like a boat on the ocean surface.

Since the bacteria, tubeworms and mussels of the cold seeps are growing without sunlight they are kind of like the plants for this deep-sea ecosystem. The food they make could be eaten by many other kinds of animals, and this is one of our current areas of research. Use the box to the right to see some of the animals endemic to the seeps (endemic means they always live there) and other deep sea animals who come to visit the seeps and perhaps dine from this deep-sea smorgasboard. Use the menu to the right to view these creatures.

These little polychaetes often swarm into balls of worms at places like the Brine Pool.

Eels are common visitors to the mussel beds, especially the Brine Pool mussel community.

These little "scrubbing bubbles" (snails) are often found in large numbers among the mussels.

Starfish like this are common visitors to both the tubeworms and the mussels. They may be able to feed on either.

Hakes like this one are common visitors to the seeps.