Cold Seep Research at MBARI S. Goffredi and V. Orphan

Scientists at MBARI are involved in many different projects, including…. Ecology - both Midwater and Benthic Benthic Biology Biological Oceanography Microbiology (Picoplankton Studies) Molecular Biology Protozoan Biology Toxicology Studies Phytoplankton Studies Biogeochemistry (Upper Ocean and Benthic) Coastal Upwelling Research

122° 30'122° 20'122° 10'122° 00'121° 50' 122° 30'122° 20'122° 10'122° 00'121° 50' 3 7 ° 0 0 ' 3 6 ° 5 0 ' 3 6 ° 4 0 ' 3 6 ° 3 0 ' 3 7 ° 0 0 ' 3 6 ° 5 0 ' 3 6 ° 4 0 ' 3 6 ° 3 0 ' M o n t e r e y S a n t a C r u z 010 km55 M o n t e r e y B a y Mt. Crushmore Clam Field Clam Flat Invert Cliff C a b r i l l o C a n y o n M o n t e r e y C a n y o n Monterey Bay Cold Seeps Axial Valley Tubeworm City within Monterey Bay…. The Benthic Ecology group studies areas known as cold seeps,

Places where energy-rich fluids are out of the ocean floor due to the geology of the underlying sediments or due to the physiological functioning of the subsurface microbial community. What is a cold seep?

Places where energy-rich fluids are out of the ocean floor due to the geology of the underlying sediments or due to the physiological functioning of the subsurface microbial community. In the late 1970s scientists discovered novel deep-sea ecosystems fueled primarily by hydrogen sulfide oxidation (chemosynthetic), rather than by plant photosynthesis. In Monterey Bay, sulfide-rich systems, teeming with chemosynthetically supported life were first discovered in the 1980's near 3200 meters depth. Since then, scientists have focused on a number of shallower cold seep areas in Monterey Bay where dense invertebrate communities have been found. What is a cold seep?

Most life on earth is fueled directly or indirectly by sunlight. There are, however, small ecosystems, such as the seeps in Monterey Bay, that depend on bacteria whose life functions are fueled not by the sun but by simple inorganic chemicals, like hydrogen sulfide.

The dominant members of the animal community in these areas are often those living in association with bacterial symbionts, and encompass a wide range of phyla, including worms and clams. Most life on earth is fueled directly or indirectly by sunlight. There are, however, small ecosystems, such as the seeps in Monterey Bay, that depend on bacteria whose life functions are fueled not by the sun but by simple inorganic chemicals, like hydrogen sulfide.

What types of questions are MBARI researchers asking about these environments? Chemistry Free living bacteria BacterialMats Animals ? ? ? ?

MBARI scientists study the chemistry of the deep sea world Here, the ROV deploys a device used to capture seawater Scientists can collect this water and analyze it for chemical compounds back in the laboratory.

How do we study the bottom of the ocean? Remotely operated vehicles -ROVs allow us to send our brain (and hands) to the sea floor Here, scientists are collecting sediment samples using the ROV manipulator

Once the sediment cores have been brought to the surface by the ROV, scientists process the cores for chemical and microbiological analyses. Here, an MBARI researcher cuts the core into sections inside a no-oxygen atmosphere glove box

Methane (µM) Sulfate (mM) SO 4 CH 4 Depth into the sediment (cm) Sediment Core from a methane-rich Monterey cold seep Bacteria feed on methane and sulfate This is a chemistry profile from the core

Methane (µM) Sulfate (mM) SO 4 CH 4 Depth into the sediment (cm) As Sulfate (SO4) is consumed by bacteria, Hydrogen Sulfide (H2S) is produced H2SH2S See How

How do bacteria influence the physical and chemical environment at seep sites? SEDIMENT SEAWATER CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH 4 METHANE SO 4 SULFATE SEDIMENT SEAWATER CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH 4 METHANE SO 4 SULFATE SEDIMENT SEAWATER 1) Localized CH 4 in sediments is utilized by anaerobic bacteria CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria SO 4 SULFATE SEDIMENT SEAWATER 1) Localized CH 4 in sediments is utilized by anaerobic bacteria CH 4 METHANE CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria SO 4 SULFATE SEDIMENT SEAWATER CH 4 METHANE 1) Localized CH 4 in sediments is utilized by anaerobic bacteria CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH 4 METHANE SO 4 SULFATE SEDIMENT SEAWATER As energy-rich seawater sulfate diffuses into sediments, it is consumed by anaerobic bacteria along with methane CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH 4 METHANE SEDIMENT SEAWATER SO 4 SULFATE As energy-rich seawater sulfate diffuses into sediments, it is consumed by anaerobic bacteria along with methane CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH 4 METHANE SEDIMENT SEAWATER SO 4 SULFATE CHEMOSYNTHETIC CLAM COMMUNITIES As energy-rich seawater sulfate diffuses into sediments, it is consumed by anaerobic bacteria along with methane

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced CHEMOSYNTHETIC CLAM COMMUNITIES

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CHEMOSYNTHETIC CLAM COMMUNITIES As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 CHEMOSYNTHETIC CLAM COMMUNITIES As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 CHEMOSYNTHETIC CLAM COMMUNITIES As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced H 2 S HYDROGEN SULFIDE

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 CHEMOSYNTHETIC CLAM COMMUNITIES H 2 S HYDROGEN SULFIDE As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 CHEMOSYNTHETIC CLAM COMMUNITIES H 2 S HYDROGEN SULFIDE As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 CHEMOSYNTHETIC CLAM COMMUNITIES As CH4 and SO4 are consumed, large consumed, large amounts of hydrogen sulfide and carbon dioxide are produced H 2 S HYDROGEN SULFIDE

How do bacteria influence the physical and chemical environment at seep sites? CH4 METHANE SO 4 SULFATE SEDIMENT SEAWATER SO 4 Methane-oxidizing & Sulfate Reducing Bacteria CO 2 H2SH2S EXCUSE ME! CHEMOSYNTHETIC CLAM COMMUNITIES H 2 S HYDROGEN SULFIDE

How do bacteria influence the physical and chemical environment at seep sites? Methane-oxidizing & Sulfate Reducing Bacteria CH4 METHANE CO 2 SO 4 SULFATE H 2 S HYDROGEN SULFIDE SEDIMENT SEAWATER CLAM SYMBIONTS CAN THEN USE THE SULFIDE PRODUCED BY THE BACTERIA (plus oxygen) TO LIVE SO 4 O 2 OXYGEN H2SH2S EXCUSE ME!

How do other organisms take advantage of bacterially produced sulfide?... Its called chemosynthesis The process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis.

How do other organisms take advantage of bacterially produced sulfide?... Its called chemosynthesis The process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis. During Photosynthesis - green plants produce organic carbon compounds from carbon dioxide and water, using sunlight as energy. These compounds can then enter the food chain.

During Photosynthesis - green plants produce organic carbon compounds from carbon dioxide and water, using sunlight as energy. These compounds can then enter the food chain. During Chemosynthesis - hydrogen sulfide is the energy source and it is either taken up by free-living bacteria or absorbed by the host invertebrates, and transported to the symbionts. The bacteria use the energy from sulfide to fuel the same cycle that plants use, again resulting in organic carbon compounds How do other organisms take advantage of bacterially produced sulfide?... Its called chemosynthesis The process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis.

What kinds of organisms in Monterey Bay use chemosynthesis for survival?... During Photosynthesis - green plants produce organic carbon compounds from carbon dioxide and water, using sunlight as energy. These compounds can then enter the food chain. During Chemosynthesis - hydrogen sulfide is the energy source and it is either taken up by free-living bacteria or absorbed by the host invertebrates, and transported to the symbionts. The bacteria use the energy from sulfide to fuel the same cycle that plants use, again resulting in organic carbon compounds How do other organisms take advantage of bacterially produced sulfide?... Its called chemosynthesis The process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis.

Large bacterial mats use sulfide for energy Scientists study these bacterial mats in order to determine the taxonomy, morphology, environmental setting, and ultrastructure of these fascinating organisms.

Scientists at MBARI study these bacteria using a variety of microscopic techniques, including…. Scanning electron microscopy Fluorescence microscopy Light microscopy

Large communities of clams and worms also use sulfide for energy MBARI scientists are studying these animals to better understand the physiology, ecology, and energetics of these animal communities.

These clams and worms dont have stomachs or mouths!! … How do they survive? Its called symbiosis Living together of organisms of different species. The term usually applies to a dependent relationship that is beneficial to both members (also called mutualism). Symbiosis may occur between plants, animals and/or bacteria

These clams and worms dont have stomachs or mouths!! … How do they survive? Its called symbiosis Living together of organisms of different species. The term usually applies to a dependent relationship that is beneficial to both members (also called mutualism). Symbiosis may occur between plants, animals and/or bacteria At seep sites, it is common for bacteria and animals to form symbiotic associations. Young animals acquire their bacterial symbionts either from their parents or from swallowing them in sea water.

These clams and worms dont have stomachs or mouths!! … How do they survive? Its called symbiosis Living together of organisms of different species. The term usually applies to a dependent relationship that is beneficial to both members (also called mutualism). Symbiosis may occur between plants, animals and/or bacteria At seep sites, it is common for bacteria and animals to form symbiotic associations. Young animals acquire their bacterial symbionts either from their parents or from swallowing them in sea water.

These clams and worms dont have stomachs or mouths!! … How do they survive? Its called symbiosis Living together of organisms of different species. The term usually applies to a dependent relationship that is beneficial to both members (also called mutualism). Symbiosis may occur between plants, animals and/or bacteria At seep sites, it is common for bacteria and animals to form symbiotic associations. Young animals acquire their bacterial symbionts either from their parents or from swallowing them in sea water. Gulp!

These clams and worms dont have stomachs or mouths!! … How do they survive? Its called symbiosis Living together of organisms of different species. The term usually applies to a dependent relationship that is beneficial to both members (also called mutualism). Symbiosis may occur between plants, animals and/or bacteria Once inside, the bacteria and animal host become partners. The bacteria multiply within the host, eventually integrating completely. The animal benefits from food produced by the bacteria and the symbiont benefits from the shelter and stable environment provided by the host.

Seep clams are no ordinary clams!!

Ordinary clam Clam chowder - yum -

Seep clams are no ordinary clams!! Ordinary clam Extraordinary clam Clam chowder - yum - Rotten eggs - yuck -

carbon dioxide oxygen sulfide water sediment bacterial symbionts Gills (symbionts) Foot Mantle Siphons Adductor muscles Unlike other animals, these clams must take up carbon dioxide (through their enlarged gills) and sulfide (through their foot) in order meet the needs of their symbionts.

In addition to strictly seep animals, a variety of other animals benefit from foraging within seep sites. These include…. Sea urchins King crabs Sea cucumbers Brittle stars Crabs

MBARI researchers continue to study Monterey Bay using an interdisciplinary approach, combining biology, with chemistry, geology, and engineering, in hopes of gaining a better understanding of our worlds oceans