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Science Feature
The Science Feature describes important research and monitoring programs or projects occurring in the sanctuaries. The current Feature presents a volunteer program conducted in and around the Gulf of the Farallones National Marine Sanctuary.
Window Seats Rock!
- the science of biogeography and why it matters-
Stephen R. Gittings, Science Program Manager
NOAA, National Marine Sanctuary Program
When I travel by air, I always seem to get a pre-assigned aisle seat. The letter after the number is a dead give-away - 10C, 5D. Sure, an aisle seat is infinitely better than a middle seat, but at the check-in counter, I always ask the agent to move me to a window. “Give me 35A or 40F if you have to, next to the lavatory if need be.” I have no interest in aisle seats on airplanes. There is nothing to see.
I love to look out the windows. From an airplane at 30,000 feet, Earth’s wonders spread like an unlabeled atlas in front of me. Patterns of endless variety and complexity scroll by. I have often mused at the idea of a hand-held contraption that would narrate to me as I flew over different parts of the country, telling me about the rivers, mountains, farmlands, circle crops, and cities below. My "Fly-Man" might even throw in a little history. Who first saw this place, and why did they choose this place to settle? What struggles did they face?
From my window in 35A, I have marveled at isolated mountain lakes (in Nevada, as far as I could tell), the Grand Canyon (it’s much better at ground level), countless oxbow lakes in the Mississippi Valley, and cloud patterns. I’ve cringed at the water-filled scars cut into South Florida, Phoenix, and Los Angeles in an attempt to colonize places otherwise too dry or too wet for humans. Sitting in 35A, I envy the person in 35F when the pilot says, "For those of you sitting on the right hand side of the plane?"
It doesn’t take a marine scientist to notice the contrast between land and sea. From a jet, the ocean looks like a giant parking lot. It has a way of hiding from view all that it holds – its terrain, its creatures, even its pain. In any event, window seats aren’t as exciting over water as over land.
Luckily for me, being a marine scientist allows me to strap on a "window seat" and some fins now and then, or gaze through the plexiglass dome of a submarine. When I splash through the ceiling of the marine world and enter its domain, I feel the same sense of fascination and wonder I do at 30,000 feet. Too bad the visibility isn’t as good! The best you can hope for underwater is only slightly better than you might get in a Pacific Coast pea soup fog.
Why my obsession with window seats? I think it boils down to the unrestricted and universal power of nature! From the elegance of the morning dew on a spider’s web to exploding mountains, nature is in charge, no matter what we think of our own abilities to control it. We can (and do) alter it in countless ways, and may even change it on a scale that we find hard to fathom, but in the end, nature calls the shots. It will heal if it can, or destroy us if it must. I am awed by that supremacy, and captivated by the beauty of the beast. In the parade that passes outside 35A, I am child straining to see every instrument, juggler, and cotton-candy vendor that goes by.
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Nature’s Designs
Nature decides its own patterns. Through forces of its own making – air, water, and fire, which interact to produce weather, erosion, and disturbance – patterns of creatures living together and interacting occupy the globe from stem to stern, from the highest mountain peaks to the deepest ocean trenches. Think of a tree-line on the side of a mountain, announcing a change from one community of vegetation to another. Or the woods at the edge of a grassy field that, depending on your inclination, marked either the limit or the beginning of your daily adventures as a child. Or the change from deciduous- to evergreen-dominated landscapes as you climb mountains or head north to higher latitudes. Or an oasis. All are limited by the natural rhythms of rainfall, temperature, and storms, soil type, moisture, and chemistry.
Patterns also exist in the ocean. More difficult to see, they are no less significant, and are determined by some of the same processes. Cold water temperatures along much of the west coast limit the northward range of tropical fish commonly found off Mexico and Central America. Altitude in another form – depth - is an important factor affecting animals and plants in the ocean. Plants are limited to the upper few hundred feet of the ocean, the actual limit depending on, among other things, water clarity. Colorful fish that you see on coral reefs you’ll not find at greater depths, while most of the many bizarre-looking species in the deep ocean are seen nowhere else. There are even "storms" in the sea. Usually the "wind" comes in the form of breaking waves, tremendously powerful currents, or mudflows through undersea canyons.
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there are other processes that make "biogeography" – the study of distributions of organisms – in the ocean realm unique from that on land. Land bridges, like the Isthmus of Panama, which serve to broaden the ranges of terrestrial creatures, are barriers to the migration of marine life. On the other hand, consider the virtues of ocean currents - what is a bridge to a barnacle is a barrier to a beetle. Ocean currents cast plant spores, animal larvae, and even adult creatures over huge areas, sometimes between distant, isolated islands, and become themselves a factor controlling distribution, somewhat like wind over land. The edges of the great ocean gyres can be barriers as well. Beyond them, unforgiving waters - too cold, too warm, too fresh, too salty - either kill émigrés outright, repress reproductive systems, or introduce them to appreciative new predators.
Within the large-scale oceanographic processes that limit distributions – ocean currents, and temperature and salinity patterns that change with latitude, longitude and depth – there are a multitude of factors that operate at smaller scales. Like land organisms, sea life is highly selective with respect to habitat. White shrimp, for example, live in highly productive environments. Reef corals need gin-clear waters. Soft-bottom worms and their colleagues generally prefer sediments of particular grain size. While a worm needs sand, kelp needs boulders or hard bottom. Specialized
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Around November, hammerhead sharks begin arriving at the Flower Garden Banks in the northwest Gulf of Mexico. Hundreds swim around the banks until March or April, and then leave. Scientists are still trying to understand why the sharks find the banks so appealing. Similar rendezvous occur on features elsewhere in the world and scientists have learned that the sharks find their way to the features by using specialized receptors in their heads to detect abnormalities in the gravitational fields around the banks.
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bacteria, and the tubeworms and mussels that harbor them, thrive only near natural methane or oil seeps, next to high salinity brine pools, or at hydrothermal vents. Creatures like soft coral, sponges, and bryozoans that filter food from the water often occupy topographic features. Raised above surrounding mud, these tenants avoid becoming clogged by sediments. Adult lobsters also take advantage of these complex structures, which provide shelter and a diversity of prey items. During mating seasons, hammerhead sharks and some other species arrive at such structures en masse, as they are easily identifiable gathering sites.
To make things even more complex, each habitat type, and the water surrounding it, is modified by other factors, such as distance from shore or from river mouths, regional weather, wave energy, and tides. Combined with the complex relationships between the species themselves (predation, competition for food and space, and various symbiotic associations) the result is the seemingly endless variety of patterns under the sea.
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Who cares about such things?
Humans have had a love-hate relationship with the sea for thousands of years. The sea is without thought or emotion, but it sometimes seems to hate our very existence. It cannot communicate, but sometimes seems to welcome us. We respond accordingly. Either our souls are stirred or our voices curse that mindless master of our fate.
It is because of the erratic behavior of the ocean that we struggle to understand it. Explorers plying the sea from the 1400s through the 1700s contemplated ocean patterns. Trade routes evolved gradually over hundreds of years, along with the recognition of the persistence of currents and weather patterns. Captains sought faster ocean crossings and to elude storm-prone waters. Nowadays, a similar, if somewhat more sophisticated, knowledge of interactions between air and water, between wind and waves, allows us to protect areas ahead of advancing hurricanes and predict the tracks of oil spills. Below the sea’s surface, the physics of salinity, temperature, density and sound allow submarines to move unnoticed in water layers that don’t allow noise to escape. The same principles allow us to pinpoint the location and strength of earthquakes, and to predict when and where tidal waves will hit coastal communities.
Knowledge of geological patterns under the sea is used daily to search for new oil and gas reserves to supply our insatiable appetite for internal combustion and a “better living through chemistry.” It also lets us find reserves of sand to rebuild beaches eroded by our attempts to contain them, allowing us to build on them before they mockingly wash away yet again.
It’s little news to any of us how we have exploited the biological resources of the sea, but most of us give less thought to the role biogeography plays in the drama. It’s all really quite simple. If you know enough about an area, you can predict what sorts of animals and plants live there. Schools of fish swarm around topographic high points. Productive rocky areas like the Grand Banks and Georges Bank once crawled with groundfish. Oysters can be found in bays with certain flushing and water quality characteristics. Salmon move into and out of specific rivers at certain times each year. Many of the great whales have well known migration routes and calving and feeding grounds. All these patterns have evolved in concert with ever-repeating, and slowly changing natural rhythms.
Biogeography and fishing are partners of necessity. Fishers have a deep-rooted understanding of small-scale biogeographic patterns in the sea. Where something lives in the ocean in any abundance, chances are you will find a fishing boat marking the spot. Historically, and unfortunately, wild ocean stocks, uncontained by barbed wire or fish ponds and bounded only by the fences of biogeography, have been harvested to unprofitable levels. Once depleted, another species is targeted and exploited. Whales are perhaps the best-known example, but many coastal stocks have shouldered the most enduring pressure. Cod, halibut, grouper, snapper, shrimp, oysters, and crabs come to mind. The conquest has not been limited to coastal waters though. In recent years even some tuna, whose habitat is the boundless open ocean, have become disgracefully sparse.
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Map showing current patterns throughout the Florida Keys. Note how clockwise and counterclockwise gyres exist shoreward of the Florida Current. These tend to carry larvae and spores from place to place throughout the region. Understanding where parent stocks are and how currents transport their young allows managers to protect important areas before they become over-harvested.
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Critical to recovery for these wild stocks is that source (parent) populations, wherever they occur within the biogeographic range of each species, remain at levels that allow for reproduction. Below certain levels, egg fertilization is limited by a low concentration of gametes in the water, or by the lack of sexually active adults. Most commercial operators either fail to recognize this or disregard it in their haste to compete for limited resources. Nevertheless, it is essential to the process of restoring fish stocks.
Our tourism and recreation exploits also depend on biogeographic principles, whether we realize it or not. Bonefish and red snapper have favorite conditions, as any fisher with a secret honey-hole will tell you. How many of us strap on a mask and fins, then snorkel around Iceland to see coral reefs? Surfers know as much about where to go to find wave energy as any physical oceanographer.
Even pharmaceutical companies and government laboratories are keen on biogeography. Programs are funded to send people around the world to collect organisms that can be tested for "bio-active" compounds. Tropical coral reefs have been targeted in the past because of the high diversity of species they harbor. Reef species also exhibit an extraordinary level of interaction. Potent chemicals are used to compete for space, to ward off predators, and to shield tissues from damage caused by exposure to ultraviolet radiation. All manner of plants and animals are collected by field teams and sent by overnight mail to the labs. When promising compounds are found, further testing and development can lead to new additives, ointments, and disease-fighting drugs.
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How do we identify patterns in the sea?
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Photographs and other data collected by satellites are used to study ocean and atmospheric circulation. Differences in water temperature, areas of high productivity, or areas with large amounts of sediments are often clearly seen on the images, leading to a better understanding of processes that affect life in the sea and on land.
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The search for patterns in nature has driven the science of oceanography from its start. The formal study of oceans began in the 1840s and focused on mapping winds and currents based on the observations of sailing vessels. Later, a ship called the Fram was frozen into Arctic pack ice in hopes that it would drift across the Arctic Sea – perhaps the first "predictive" oceanography. The first comprehensive oceanographic survey took place in the 1870s aboard the HMS Challenger. From that exploration alone, information from water and bottom samples, depth measurements, and collections of marine life from around the globe fills 50-volumes. The collections produced 5,000 species new to science!
In the modern age, satellite photographs and measurements help us understand very large-scale ocean phenomena and some small-scale features (surprisingly small, in fact, considering the distance at which the measurements are made). Drifting and anchored instruments add critical detail on current speeds and directions. Highly sophisticated echo-sounding devices allow ships to produce detailed maps of the seafloor, and instruments lowered on cables provide measurements of water quality throughout the water column (before the age of microprocessors, such measurements were made at only a few depths by collecting water samples).
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Small submersibles like the DeepWorker 2000 are valuable tools that enable scientists to view the ocean on its own terms, leaving behind the days of judging the sea based on critters trapped in a net, dragged to the surface, and strewn across the back of a ship.
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Biologists still use trawls, but some are complex, electronically operated gadgets with multiple nets that open and close at selected depths. Biological information is being supplemented by more and more sophisticated underwater visualization techniques. Scuba diving in shallow water, and submersibles and remotely operated vehicles in deeper water, provide digital video and still photos and opportunities for collection and experimentation. Coupled with accurate tracking systems that record the locations of samples, and other geographic and oceanographic information, patterns are still emerging, clarifying our understanding of the relationships between creatures and their habitats, and the impacts of humans on them. It seems inevitable that new tools, like small submersibles that can withstand the pressures of full-ocean depth, and autonomous (untethered) underwater vehicles, will extend our capabilities even further in the not-too-distant future.
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Map showing the locations of many topographic features in the northwest Gulf of Mexico. Those to the east of the line running from Matagorda Bay to the shelf edge originated from uplift by ancient salt domes. Those off south Texas were formed when low sea level stands eroded pre-existing carbonate bedrock.
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So What?
It is informative to look at a case study to understand how resource management decisions can be based on biogeographic studies. The study also illustrates how biological, physical, geological investigations can work together and allow managers to impose meaningful protective limits on potentially damaging human activities.
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Production platforms like this one near the East Flower Gardens Bank are a common sight in the northwest Gulf of Mexico. There are over 4,000 platforms, along with over 25,000 miles of pipeline carrying oil and gas to land from points well over 100 miles offshore. Without adequate safeguards, drilling and production operations could damage natural resources in the region. Fortunately, offshore operations are heavily regulated and incidents that cause environmental harm are rare.
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The Situation: In the 1960s, divers and scientists discovered actively growing coral reefs on two of the many hard bottom banks (topographic features raised above the seafloor) in the northwest Gulf of Mexico. The reefs were at the edge of the continental shelf, over 100 miles offshore. Both the nature of the reefs and the assemblages on other banks in the region were only poorly known.
Possible threats to these resources were just becoming apparent. Until then, most oil and gas operations were on land or in shallow water environments. It had become obvious that technological development would enable the production of hydrocarbon reserves farther offshore. Spills and other problems associated with this production could harm natural resources in the offshore environment.
Other threats to the banks also existed. Offshore fishing in the northwest Gulf targeted menhaden (an inedible fish processed mostly for fish meal and oil) and shrimp, but fishing on offshore banks was conducted by longlining (long bottom lines miles in length with intermittent, baited hooks) and hook-and-line techniques. They targeted primarily red snapper. If the ecosystems on the banks were at all fragile, some fishing techniques could harm them. Coastal development, particularly to support the chemical industry (e.g. refineries) and offshore services, was occurring at a rapid pace. Commercial ships occasionally anchored on the banks, either waiting for orders or stopping to make repairs. Recreational scuba diving at the time was minimal, owing to the remoteness of most banks.
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In the 1970s and 1980, Texas A&M University’s two-person submersible Diaphus was used to explore the banks of the northwest Gulf of Mexico. The job of the swimmer, sitting on the sub, was to detach the lifting line after launch and reattach it prior to recovery. Everyone wanted the job, as it broke up the monotony of the day for those who remained on the ship as the sub pilot and observer probed the depths of the Gulf.
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Information Needs: One of the responsibilities of the Department of Interior’s Bureau of Land Management was to regulate offshore oil and gas operations, in part to minimize environmental impacts. BLM needed information to decide whether to allow drilling and production operations on or near the banks. If it decided to allow such operations, then what conditions would be imposed to limit damage from anchors, cables, platforms, normal discharges, well blowouts and other accidental spills? Where would pipelines be laid and under what restrictions should they operate? And did all the banks warrant the same level of protection?
The answers to these questions clearly required an understanding of the geological, physical and biological dynamics of the region in general, and the banks in particular.
Approach: BLM issued contracts for several studies to address these questions. From the late 1960s through the early 1980s, geologic, oceanographic, submersible, and diving expeditions to the banks produced detailed maps, characterized the geology and origin of the banks, located faults, inventoried biological assemblages, and described seasonal patterns of currents and other water quality characteristics. Such research, combined with other scientific studies on the effects of sediments, drilling fluids, and oils on corals, and models that predicted how particles and liquids might move under varying conditions, provided BLM with the information necessary to develop appropriate rules to protect sensitive assemblages.
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Dr. Jim Gardner, of the U.S. Geological Survey, produced this image using high resolution data from an acoustic survey conducted in 1990. Using colors to indicate depths, the different colors also show the different biological communities on the bank. The two red areas contain coral reefs. The much larger orange area is dominated by coralline (limestone-forming) algae and sponges. Note the large collapsed area on the lower right hand side of the image. This graben is over a mile across and is forming as dissolution slowly removes salt from beneath the surface of the bank.
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Data: The studies showed a region with dozens of topographic features, most originating from uplift caused by the vertical migration of domes of 150 million year old salt from layers now deep beneath the Gulf of Mexico. Some banks rise 400 feet or more above the surrounding sand and mud that covers much of the Gulf’s seabed. Since their birth, sea level changes and many other natural forces have modified each bank’s structure. Each contains biological assemblages whose development and whereabouts are controlled mainly by depth, distance from shore, bottom type, water clarity, and temperature, with other factors playing supporting roles. Water movement in the region, and over and around the banks is predictable, but quite variable.
Below are some of the data gathered from expert divers for several of the banks in the region, along with data collected more recently from two areas elsewhere, the Dry Tortugas (west of Key West, Florida) and Gray’s Reef (off Georgia’s Atlantic coast). We will use the latter two for comparison purposes later.
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Click on the image for large view.
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* a diverse and well-developed assemblage, dominated at Gray’s Reef by sponges and ivory bush coral (a non-reef-building variety), also including tunicates, hydroids, soft corals, bryozoans, and mussels
^ the algal-sponge community at Gray’s Reef is composed of different species that that on the banks in the Gulf of Mexico
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Pictures from the Flower Gardens and Stetson Bank. Corals cover nearly half the bottom at the Flower Gardens. The other half consists of the remains of dead corals. At Stetson Bank, fire coral (orange) and sponges cover rock outcrops, but only as a thin crust underlain by claystone and siltstone bedrock (gray).
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It became clear, during the course of this research, that banks along the edge of the continental shelf had assemblages that were different from those on banks closer to shore. Both Stetson and Sonnier Banks, for example, are dominated by similar fire coral and sponge assemblages, even though their shallowest depths are the same as those of the coral reefs at the Flower Gardens. The corals on Stetson and Sonnier grow in patches; the banks are not building upward as a result of skeletal formation by the corals (that is, they are not true coral reefs). The sandstone bedrock on the banks is clearly visible. The Flower Garden Banks, on the other hand, contain 20 different types of massive reef-building corals. There is no visual evidence of bedrock; it has all been overgrown by coral.
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To compare the fish assemblages of Sherwood Forest and the Flower Gardens, produce a report from Sherwood Forest and compare it to the Flower Gardens report. You will see that the two sites share 4 of their top 10 species, ranked by sighting frequency. By comparison, Sherwood Forest shares two of its top 10 species with Sonnier Bank, and only onewith Stetson.
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Go again to the REEF website and produce a fish report for Gray’s Reef and compare it to reports from the Flower Gardens, Stetson, and Sonnier. Gray’s Reef shares 2 of its top 10 species with Sonnier Bank (blue angelfish and cocoa damselfish—both are tropical species). Gray’s Reef doesn’t share a top-ten sighting frequency with the other mentioned sites (Stetson Bank, Flower Gardens )
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An analysis of the remainder of the data revealed that the similar assemblages on each of the two pairs of banks reflected distinctly different environmental conditions along the shelf edge and the mid-shelf. Even though Stetson and Sonnier Banks are separated by 180 km, their annual temperature cycles, water clarity, and surrounding depths are similar, as they are for banks along much of the middle continental shelf. Details of the biological assemblages, including fish species and bottom-dwellers, reflect these similarities. The East and West Flower Garden Banks are much closer together, separated by roughly 15 km. Considering this, and the fact that their geological and physical characteristics are alike, the similarity of their benthic (bottom) assemblages is not surprising.
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Like Stetson and Sonnier Banks, Gray’s Reef has a well-developed sponge community on a pre-existing rock substrate (gray colored rock). Though most of the species are different, in all three cases the current inhabitants of the banks do not produce the substrate, as they do at the Flower Gardens.
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It is interesting to compare the assemblages on these banks to those on similar features in Florida and Georgia. Like the Flower Gardens and Stetson Bank, the Florida Keys and Gray’s Reef are national marine sanctuaries, designated by virtue of nationally important natural and cultural resources. Though none are entirely closed to fishing, each regulates activities that damage habitats required by fish and their prey.
The coral-dominated habitats at the Flower Gardens and Sherwood Forest (in the Tortugas, 70 miles west of Key West) make them appear more closely related to each other than to Stetson Bank and Sonnier Bank, which are much closer to the Flower Gardens. Because of the water they reside in, the Flower Gardens and Sherwood Forest emulate true tropical environments, even though they are north of the Tropic of Cancer. They are not identical though, partly due to the large distance between them.
Stetson and Sonnier Banks are in waters that are somewhat more temperate (colder, more seasonally variable, more turbid) than those around the Flower Gardens. And while the bottom on these banks looks more like Gray’s Reef, which many people call a "live bottom" habitat, there is a greater tropical influence. Several species of reef corals exist on Stetson and Sonnier, and among the fish, nearly all are tropical species. Few temperate species are found, as they are at Gray’s Reef. Common species at Gray’s Reef, like belted sandfish, sheepshead, bank sea bass, black sea bass, spottail pinfish, and Atlantic spadefish, are much rarer at the other sites or elsewhere in the tropics.
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| Sherwood Forest, in the Tortugas (left), and the Flower Gardens in the northwest Gulf (right), have strikingly similar coral formations, these great star coral colonies being good examples. |
The data on physical, biological, and geological dynamics were used to develop a model that describes the ecological factors controlling distribution of plants and animals on the banks of the northwest Gulf of Mexico. The figure below summarizes that model:
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| This model was developed by Tom Bright, Dick Rezak, and Dave McGrail in the early 1980s to explain the factors that control biological community development on the banks of the northwest Gulf of Mexico. It shows how distance from shore, depth, water temperature, and currents interact to influence the location and depth range of these assemblages (from Rezak, R., T.J. Bright, and D.W. McGrail. 1985. Reefs and Banks of the Northwest Gulf of Mexico: Their Geological, Biological and Physical Dynamics. John Wiley and Sons, N.Y. 259 pp. |
For a great on-line exercise that investigates links between fish and their habitats, go to http://www.vims.edu/bridge.
NOAA’s National Marine Sanctuary Program recently partnered with the BRIDGE, an on-line Ocean Science Teacher Resource Center containing the best marine education resources available. It provides educators with a convenient source of accurate and useful information on global, national, and regional marine science topics, and gives researchers a contact point for educational outreach.
The BRIDGE presents monthly lesson plans that make on-line marine science data sets easily accessible to teachers and students. The first data tip focuses on marine sanctuaries in the southeast, including Gray's Reef, Florida Keys, and Flower Garden Banks. Students learn about the sanctuaries and environmental conditions that make each |
Decisions: Now it was decision time. The characterizations made it clear that oil and gas development in the northwestern Gulf would have to be controlled near the banks, as many contained sensitive biological communities. But sensitivities varied among the banks. BLM, a portion of which is now called the Minerals Management Service, in collaboration with regional scientists, developed stipulations that required operators to change the way they do business when drilling or producing near the banks. Banks were categorized by their sensitivity. There were "No-Activity Zones" on top of the banks, and depending on sensitivity, "One-Mile Zones," "Three-Mile Zones," and "Four-Mile Zones" around 28 banks. Each required certain limits on activities. The earliest stipulations, imposed in 1974, are summarized below:
1. "No Activity" Zones were rather self-explanatory. No activity was allowed. This was partly for resource protection and partly due to the instability of the features. Active faults are common on the banks, and no one wanted oil and gas platforms tipping over! But it also extended to industry vessels. It prohibited anchoring or any other vessel-related operations that might disturb the natural resources over the banks.
2. Operators in "One-Mile" Zones were required to shunt "drill muds" (fluids used to lubricate the drill string, maintain pressure, and facilitate removal of cuttings) and cuttings through downpipes to within 10 m of the seabed. Normally they would discharge these wastes at the surface. According to research on physical oceanography at the banks, shunting would stop sediments from smothering corals, and eliminate exposure to toxic fractions of the muds on the shallow portions of the banks. Operators in these zones were also required to establish monitoring programs on the banks to track the condition of benthic resources.
3. In "Four-Mile" Zones around the Flower Gardens, and "Three-Mile" Zones around other banks in the region, operators were required to shunt fluids and cuttings, but not to monitor.
Following the designation of the Flower Garden Banks National Marine Sanctuary in 1992, other actions were taken to further protect the banks:
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Plumes of turbid water, whether caused by drill muds, drill cuttings, or other spilled material, damage or kill creatures that live in clear water. For this reason, controls on such discharges are necessary in the normally transparent offshore waters of the Gulf of Mexico.
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- Within the "Four-Mile" Zone around the Flower Gardens, MMS required operators to "shut in" pipelines for inspection and repair if the oil pressure drops more than 10% below normal operating pressures (most operators shut down if pressure drops more than 15%).
- Operators conducting seismic surveys to identify oil and gas reservoirs (the surveys are not prohibited by sanctuary regulations) are required to notify the sanctuary before conducting field work and, if necessary, to arrange for the removal and replacement of mooring buoys used by dive charters and other boats.
- Operators responding to spills in designated areas surrounding the Flower Gardens (identified by computer models as posing a 10% or greater risk of spill-contact within three days) are required to notify the sanctuary. Over 400 lease blocks, each three miles on a side, are affected by this requirement.
- Other issues related to oil and gas development have also been addressed, including the use of dispersants to remove oil from the ocean surface following a spill, the review process for exploration and development plans, and platform removal requirements (platforms must be removed at the end of their production life).
MMS was not able to deal with all the threats to the banks in the northwest Gulf. Anchoring by non-industry vessels, for example, is not under the authority of MMS, nor is commercial or recreational fishing, or recreational diving, or vessel discharges. All these have some impact on the sensitive communities of the banks. With the designation of the Flower Gardens Sanctuary, the National Oceanic and Atmospheric Administration was granted protective authority under the Marine Protection, Research and Sanctuaries Act of 1972, and adopted regulations to reduce these threats. These imposed prohibitions on anchoring, destructive fishing, collecting, and certain types of discharges.
Over twenty years of monitoring at the Flower Gardens have shown that the regulations imposed by MMS and NOAA are working. Very few changes in coral cover, growth, diversity and a host of other measures of environmental condition have ever been documented. Natural events rather than human use caused the few changes that have been seen. But threats remain, particularly the threat of anchoring by large, foreign-flagged ships. Many operators remain ignorant of prohibitions on anchoring in the sanctuary. Recent efforts, however, have led to the revision of international laws governing ship traffic and are likely to increase awareness of ship captains to the threats posed by anchoring on coral reefs.
The Quest Continues…
Multi-disciplinary biogeographic studies like those used in the Gulf of Mexico are necessary to grasp the complex relationships between earth, water, air, and living things. They are widely recognized as valuable because we have come to understand that nature is more intertwined that we could ever comprehend. Like pick-up sticks, removing one from the mix affects the rest - if not immediately, inevitably. To tinker with nature without fear of retaliation, we must recognize its parts, know how they fit together, and understand how they relate to one another.
So, pondering the landscapes scrolling by the window in 35A, the enormous, yet elusive complexity of nature grabs and keeps my attention. A mind-boggling collage of ecological texture hints at millions of years of Earth’s history. Draped with the mosaic of hundreds of years of human enterprise, endless detail and untold stories dwell in the patterns below. Yet, slowly emerging is another thought. It occurs to me that even the smallest mouse in the woods on that mountainside below depends on the health of an environment whose breadth it could never see or comprehend. In turn, the pattern rushing past seat 35A could depend on that little mouse.
I’m truly sorry man’s dominion
Has broken Nature’s social union,
An’ justifies that ill opinion
Which makes thee startle
At me, thy poor earth-born companion,
An’ fellow-mortal!
- Robert Burns, To A Mouse (upon disturbing its nest with a plow)
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Additional reading and related images:
National Marine Sanctuary Program:
http://www.sanctuaries.nos.noaa.gov/welcome.html
Flower Gardens and Stetson Bank: http://www.sanctuaries.nos.noaa.gov/oms/omsflower/omsflower.html
Flower Gardens Banks NMS Regulations:
http://www.sanctuaries.nos.noaa.gov/oms/
omsflower/omsflowerpubdoc.html
Minerals Management Service (MMS):
http://www.mms.gov
MMS funded studies: http://www.gomr.mms.gov/homepg/
regulate/environ/flow_gar/flowgard.html
USGS Images:
East Flower Garden Bank: http://walrus.wr.usgs.gov/
pacmaps/ef_persp.html
Stetson Bank: http://walrus.wr.usgs.gov/pacmaps/sb_persp.html
West Flower Garden Bank: http://walrus.wr.usgs.gov/pacmaps/wf_persp.html
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