December 2012 Coastal Scuttlebutt
DECEMBER FOURTEENTH
Pentagon with a new color scheme.
Painting the Pentagon green
An authority on climate change, a business consultant and an outspoken critic of the Keystone XL pipeline, was interviewed yesterday and quoted in Huffpost as follows, with his name redacted by yours truly:
In an interview with HuffPost Live Thursday, __ spoke out against the building of the Keystone XL pipeline, warning that “all Americans should be outraged” about the national security implications of the project.
“I want to stop paying big oil and I want to start seeing a green economy in this nation,” he told host Alicia Menendez. “And big oil is pushing Keystone, and Keystone is essentially going to maintain the status quo for another 25 years. And during that time I can only imagine the impact it’s going to have on our environment and, indeed, our national security.”
__ said that “all Americans should be outraged about the potential implications for our national security” because the pipeline “keeps us hopelessly addicted to oil.”
If you assumed that the anonymous interviewee is a member of the ‘green’ community you’d be correct, in that he is technically trained on energy issues, he thinks in quantitative terms and he spent many of his professional years dressed in green. Nevertheless, our insightful commentator is not James Hansen or Bill McKibben. In fact, this insightful commentator is former U.S. Army Brigadier General Steven M. Anderson.
The Pentagon is one of the nation’s largest consumers of liquid hydrocarbons and thus one of its most significant generators of greenhouse gases, especially CO2. A few forward-thinking military leaders, such as B. G. Anderson, recognizing that climate change poses a very significant national security threat, have advocated an aggressive campaign to transform the Pentagon from brown to green. They want to convert gas guzzling military weapons systems, from tanks to aircraft carriers and the planes they carry, to renewable, green forms of energy, such as liquid hydrocarbon fuels produced by algae.
DECEMBER THIRTEENTH
Hiking the routes and roots of our ancestral change
Note how much of this journey is coastal.
On December 12 PBS Newshour presented an interview with Paul Salopek, an award-winning journalist who is about to set out on foot on a 21,000 mile seven year coastal journey. Mr. Salopek will travel from the seat of our species in the Great Rift Valley in Africa. He’ll hike north and east through Asia, southeast Asia and the deltaic center of civilization in the Middle East, east across the Bering Straits into the New World and then all the way south to Patagonia.
He’ll be documenting rapid global changes occurring re population and natural resource availability, ecosystem health, human health, climate change and political tensions, interacting with random locals, political leaders, scientists and other authorities, using the latest in miniaturized electronic communication equipment and satellite-driven ground positioning systems. His support network is already in place, thanks to National Geographic and other granting organizations but he’ll not be wearing any corporate logos or selling anything but the truth.
Wish I could tag along with my mental faculties intact but with my physical problems shrunk to the scale of a house wren or maybe a ladybird beetle.
DECEMBER TWELTH
Rick Scott, classic gulf GOP Goobernator
Despite the indifference of Rick Scott, Florida state workers plan for climate change
One of my regular informants emailed this post by Christina DeConcini published yesterday in ThinkProgress Climateprogress about a recent coastal meeting in Florida in which the theme was…drum roll…planning for climate change. This may sound like an absolutely reasonable subject on which to host an official meeting along the gulf coast but the fact is that Florida remains the sole gulf state that has ever officially held meetings to plan for the impacts of global warming and sea level rise!
Here’s a quote:
“Think globally, act locally” is a slogan that aptly describes what I witnessed last week at the Southeast Florida Climate Leadership Summit. At the event, local government officials from four counties gathered to discuss how to mitigate and adapt to climate change’s impacts.
Yep, you heard that correctly: government officials in the United States — in a “purple” state, no less — came together in a bipartisan manner to address climate change mitigation and adaptation. In fact, mayors, members of Congress, county commissioners, and officials in charge of water issues in the state discussed how to move forward with action plans in response to sea-level rise – a climate change impact which is not theoretical, but happening now.
Back in 2008, when I still had access to the Louisiana Governor’s Coastal Office van, I attended numerous meetings of the (languishing) federal Gulf of Mexico Program (GOMP), a program in search of a mission that was superseded by a state-run organization…the Gulf of Mexico Alliance. IMHO, GOMA resulted from a coup led by former Mississippi Governor Haley Barbour.
I was being encouraged to retire around that time and what I had to say about the state of the gulf was far too candid for the attendees and for their respective GOP ‘Goobernators.’*
As I write this I’m flashing on one of Louisiana’s stalwart loyal chair warmers at meetings such as this, a man so cautious and incurious as to have never taken a minority position or breathed a critical word about anything in the entire 20 years since I’ve known him.
As you can imagine, meetings attended by such characters were maximally bureaucratic, minimally informative and dominated by subcommittees and education-outreach activities dancing around the most innocuous, non-substantive and trivial topics.
*That’s an amalgam between southern goobers, governors and Arnold Swartzenegger lingo.
DECEMBER ELEVENTH
Chip Groat still in the news re fracking safety
Chip Groat with black eye reminiscent of the Little Rascal's dog, whatever her name was.
In today’s NOLA.com Mark Schleifstein did his usual thorough job digging into the charges of conflict of interest swirling around Chip Groat, Ph.D.,* newly-appointed president and CEO of the Water Institute of the Gulf. As Schleifstein points out Groat authored a white paper on the risks of hydraulic fracking – but he failed to disclose the fact that while drafting the paper he was employed by an energy company involved in hydraulic fracking.
Unimpeachable technical credibility is the sole stock in trade that the Water Institute can bring to Louisiana’s struggling and underfunded coastal protection and restoration program. Fracking is not a topic likely to be addressed by the institute, so Groat’s black eye will hopefully be short-lived.
On the other hand, public concern re fracking is not going away, with proponents and opponents of the process becoming increasingly polarized.** Given Louisiana’s history of support for the energy industry and anti-regulatory fervor we don’t need another reason to be suspicious of science in the coast.
*I’m a long term associate of Dr. Groat and my sense is that he has exactly the background needed to head the Water Institute. Thus I remain supportive of his appointment.
**Note the soon-to-open film Promised Land, with Matt Damon, Frances McDormand and John Krashinski, a documentary about fracking. This film will invite comparisons with environmental documemtaries by Al Gore and Michael Moore.
DECEMBER TENTH
Cuyahoga River...no longer flammable
Imagine wetlands in 2012 without the Clean water act
Since April 20, 2020, when BP oil began gushing uncontrollably into the gulf south of Grand Isle, we’ve been hearing a lot about the Clean Water Act, which is the primary legal mechanism for redressing grievances with the company that did the damage.
Fifty years ago when the act was passed in 1972 we were using primitive technology, with Louisiana oil and gas production just starting to move offshore into the gulf. We had tapped into most of the major deposits of onshore oil and gas and had already passed beyond peak oil for onshore reserves.
It turns out that Section 404 of the CWA provides the primary basis for a regulatory system for wetlands (both coastal and inland). It ain’t great but just imagine its absence. Note the fact that there are far fewer teeth in Section 404 than there are exclusions and loopholes.
James Salzman posted an insightful article in Slate.com that refers to the Clean Water Act, passed over Richard Nixon’s veto pen in 1972, was the most inspired and important piece of environmental law ever passed.
Summary
The principal law governing pollution of the nation’s surface waters is the Federal Water Pollution Control Act, or Clean Water Act. Originally enacted in 1948, it was totally revised by amendments in 1972 that gave the act its current shape. The 1972 legislation spelled out ambitious programs for water quality improvement that have since been expanded and are still being implemented by industries and municipalities.
This report presents a summary of the law, describing the essence of the statute without discussing its implementation. Other CRS reports discuss implementation, including CRS Report R40098, Water Quality Issues in the 111th Congress: Oversight and Implementation, and numerous products cited in that report.
The Clean Water Act consists of two major parts, one being the provisions which authorize federal financial assistance for municipal sewage treatment plant construction. The other is the regulatory requirements that apply to industrial and municipal dischargers. The act has been termed a technology-forcing statute because of the rigorous demands placed on those who are regulated by it to achieve higher and higher levels of pollution abatement under deadlines specified in the law. Early on, emphasis was on controlling discharges of conventional pollutants (e.g., suspended solids or bacteria that are biodegradable and occur naturally in the aquatic environment), while control of toxic pollutant discharges has been a key focus of water quality programs more recently.
Prior to 1987, programs were primarily directed at point source pollution, wastes discharged from discrete sources such as pipes and outfalls. Amendments in that year authorized measures to address nonpoint source pollution (stormwater runoff from farm lands, forests, construction sites, and urban areas), now estimated to represent more than 50% of the nation’s remaining water pollution problems.
Under this act, federal jurisdiction is broad, particularly regarding establishment of national standards or effluent limitations. Certain responsibilities are delegated to the states, and the act embodies a philosophy of federal-state partnership in which the federal government sets the agenda and standards for pollution abatement, while states carry out day-to-day activities of implementation and enforcement.
To achieve its objectives, the act embodies the concept that all discharges into the nation’s waters are unlawful, unless specifically authorized by a permit, which is the act’s principal enforcement tool. The law has civil, criminal, and administrative enforcement provisions and also permits citizen suit enforcement.
Financial assistance for constructing municipal sewage treatment plants and certain other types of water quality improvements projects is authorized under title VI. It authorizes grants to capitalize State Water Pollution Control Revolving Funds, or loan programs. States contribute matching funds, and under the revolving loan fund concept, monies used for wastewater treatment construction will be repaid to a state, to be available for future construction in other communities.
DECEMBER NINTH
Boustany 3rd District Congressman
Charles Boustany, Jeff Landry
Laurey McGaughy reported in today’s The Times-Picayune that the runoff election for Louisiana district 3rd seat ended decisively as expected yesterday with 60% of the votes cast for Charles Boustany and only 40% for Jeff Landry. The coastal implications of this runoff are unclear but Landry’s supporters also supported the notorious Louisiana Science Education Act, bane to science teachers and students alike.
Landry was heavily favored by Tea Party groups and picked up several key conservative endorsements, including the now-split FreedomWorks, Citizens United, Tea Party Nation and the Family Research Council, which hosts the annual Value Voters Summit.
This presumably put him at odds with support for federal restoration funding ‘earmarks,’ which could have become a serious coastal issue during the next two years.
DECEMBER EIGHTH
Chip Groat on the hot seat over report he authored on fracking risks…while under a lucrative contract to a drilling company that downplays the dangers of fracking
Charles C. "Chip" Groat, Ph.D.
On December 6, Andrew C. Revkin posted a scathing report in his NY Times blog dot.earth from the administration of the University of Texas Austin. It seems that Charles Groat, former director of the UT Energy Center and newly appointed to direct the Water Institute of the Gulf, has been implicated as having a serious conflict of interest as the author of a white paper on hydraulic fracturing.
Terrence Henry published a followup report on Groat’s situation yesterday on NPR’s State Impact Texas. Dr. Groat failed to disclose the fact that he was employed by a large drilling company while writing the report.
On September 12, 2012 James Gill published a strongly worded opinion piece in The Times-Picayune about Dr. Groat’s clear conflict of interest on this issue. Groat has resigned as head of the UT Austin Energy Center.
This is an awkward subject for me to write about because I’ve known Chip for a very long time, because we need all the technical expertise we can get and because I want him and The Water Institute of the Gulf to succeed.
DECEMBER SEVENTH (Pearl Harbor Day)
Fracking pipe ready to go.
Louisiana (Ground and Surface) Water Commission holds first meeting…will look at fracking!
Amy Wold reported yesterday in The Advocate about the first meeting of the newly recreated Louisiana Water Commission, held Wednesday in Baton Rouge. This body will look at both ground and surface water availability and quality, which will force it to deal with some interesting political issues.
Originally formed by the state Legislature in 2001 as the Louisiana Ground Water Resources Commission, the Legislature changed its name earlier this year to the Water Resources Commission to give the board more authority to gather information about surface water resources in the state as well as groundwater…
…Although the new commission will continue to be managed by the Office of Conservation at the state Department of Natural Resources, its role in examining water resources will expand.
Previously, the commission dealt with only groundwater issues and had authority to direct the Commissioner of Conservation to put together rules and regulations for designated regional water resource groups.
While retaining the previous duties, the new commission will be tasked with creating an inventory of the availability and use of the state’s surface water, including anticipated future demands on surface water.
Scott Angelle, chairman of the Water Resources Commission, said the commission won’t have regulatory authority over surface water — instead, its role will be to gather information on the resource.
You can bet that Secretary Angelle is happy not to have to deal with regulations!
In addition to expanded duties, the commission’s board also increased to include new members, including representatives from the Ports Association of Louisiana, Louisiana River Pilots’ Association and legislative appointments representing residential water consumers.
This change is critical in that surface water issues include the optimization of the Mississippi River river to carry commerce and support major river diversion projects.
In March, the commission, under its previous name, submitted a report to the Legislature outlining a number of issues that should be addressed.
Matthew Reonas, education and marketing representative with DNR, said action on some of the issues in the report, including the need for better groundwater monitoring and public education about water resources, has already begun.
“We didn’t really have a monitoring network that was robust enough to manage the resource,” Angelle said.
An agreement announced earlier this year between DNR and the U.S. Geological Survey will bring back monitoring on about 200 wells statewide, bringing the total to about 400 wells.
John Lovelace, reports specialist with the USGS Louisiana Water Science Center in Baton Rouge, said the USGS has been working with DNR for about a year to come up with a way to fill in the gaps in water monitoring information.
To help fill those in, monitoring of groundwater levels will increase around the state. The work will include updating groundwater level maps, some of which haven’t been updated since the 1980s, and some aquifers that have never been mapped, Lovelace said.
The additional monitoring will include more monitors looking for saltwater intrusion into aquifers and at the impacts of shale fracturing, also known as “fracking.”
Hydraulic fracturing is a process used to get to oil or gas in shale layers of soil.
The process involves drilling down to a shale layer and then horizontally applying a high-pressure water/chemical mix to crack the shale, which allows the oil or gas to be collected.
Lovelace said the monitoring plan includes looking for water quality changes in areas where the fracking process is in use or will be used in the future.
“There have already been issues in other parts of the country of some of this (fracking liquid) showing up in water,” Lovelace said.
This process has become increasingly contentious. There’s even a new movie coming out on January fourth, Promised Land, with Matt Damon, Frances McDormand and John Krashinski.
Check out this article on fracking secrets by Ben Elgin, Benjamin Haas and Phil Kuntzon November 30 in Bloomberg News. Now check out the membership of the Louisiana Water Resources Commission. Energy, petrochemical and land owner issues will never agree to a law forcing the disclosure of fracking fluid ingredients.
DECEMBER SIXTH
Gulf fisheries production on the rise
Seafood consumption in the Mediterranean was low during the Pleistocene Epoch, but has apparently increased throughout the Holocene Epoch. As sea level rises globally it will encounter flood soils different from the silts and clays a nearshore slope ratio different from what the past.
This article describes a surprising lack of seafood consumption by humans at the end of the Pleistocene Epoch. Here’s the entire post:
Sicilian cuisine is famous for the bounty of the Mediterranean: fish, clams, mussels, shrimp. But 20,000 years ago, around the time of the last ice age, the first modern humans who arrived in the region ate very little seafood, researchers report after studying the remains of human skeletons.
“The source of the dietary protein consumed mainly originated from the meat of medium to large terrestrial herbivores,” said the report’s first author, Marcello Mannino, an archaeologist at the MaxPlanckInstitute for Evolutionary Anthropology Maxin Germany.
The remains were found in a cave on the small island of Favignana, which thousands of years ago was part of Sicily. Sicily itself was connected to the mainland by a land bridge, allowing humans to cross over.
Dr. Mannino and his colleagues did an isotopic analysis of the remains to determine what the settlers were eating. They reported their findings in the journal PLoS One.
By the time they arrived in Sicily, modern humans had yet to develop sophisticated fishing techniques. Moreover, Dr. Mannino said, the Mediterranean is an enclosed sea, poor in nutrients compared with oceanic regions. By now, he continued, overfishing has taken its toll on the sea’s marine resources.
“Modern fishing methods essentially wipe out anything that is present in a given area and then essentially destroy the sea bottom,” he said.
DECEMBER FIFTH
Robert S. Young, Ph.D.
Sand dunes in New York vs. sand berms in Louisiana
I call your attention to a pair of related articles in the NY Times on protecting New York and New Jersey beach-front communities, using artificially-enhanced sand dunes. In the first article, Reporters Mureva Navarro and Rachel Nuwer West interviewed two well-known coastal geologists from North Carolina with exceptional knowledge of beach dynamics…Dr. Robert Young, with whom I corresponded during the infamous sand berm debacle in 2010; and Dr. Orrin H. Pilkey, whom I met as a grad student at Georgia.
Dr. Young was one of the most outspoken critics of Governor Jindal’s scheme to build temporary sand berms during the BP disaster. I couldn’t imagine a more objective scientist to comment on the Louisiana project, in that he had no dog in the fight and was not seeking a consulting contract.
Here are quotes from both Young and Pilkey:
Orin H. Pilkey, Ph.D.
“If you put up a sea wall, the beach will disappear because you stop its ability to move landward,” said Robert S. Young, director of the program for the study of developed shorelines at Western Carolina University in North Carolina. And restoration projects, he said, need to be maintained, at great financial cost.
Homeowners along the coast are undergoing a similar rethinking. But some experts say dunes can lend a false sense of security.
“People think that if we have a nice big dune, they don’t have to worry and can build a high rise,” said Orrin H. Pilkey, professor emeritus of earth and ocean sciences at Duke University. “I think that’s a very serious shortcoming of dunes.”
Rachel Nuwar West: He supports dune restoration but also proposes limiting and mitigating development, including not rebuilding destroyed homes next to the beach and elevating others onto stilts to avoid flooding in the event that dunes are overtopped.
A related article by Rachel Nuwer West expands on the topic and includes the following Pilkey quote:
“If I was king, we would restore dunes, but we wouldn’t rebuild destroyed homes close to the beach, and we’d move some buildings back anyhow,” said Orin H. Pilkey… “We would also put in regulations prohibiting intensification and development.”
Consider the difference between (1) a $260 million sand berm ‘project’ in Louisiana, enlisting every available dredge boat in the country in a highly-charged emergency atmosphere to pile up sand berms ‘designed’ on the back of an envelope by dredging contractors gathered at a campaign fund raiser; and (2) a thoughtfully designed beach nourishment projects, using accepted engineering standards and technical oversight.
DECEMBER FOURTH
Menhaden harvested in the gulf, not of great interest to the hook and line folks but they should reflect the health of the coast.
Are gulf fisheries defying the laws of thermodynamics?
Thirty years ago, a decade before Louisiana’s coastal restoration program was initiated, my colleagues and I at LSU’s Coastal Studies Institute and the (now defunct) Center for Wetland Resources were attempting to quantify the practical implications of the increasingly evident decline of the Mississippi River delta. For the most part, the general public was blissfully unaware that south Louisiana was sinking out from under our feet.*
We systems ecologists were interested, among other things, in predicting the impacts of the delta collapse on the continued world-class fishery production along the northern gulf coast. In 1982 I co-authored a paper attempting to connect the amount of energy captured each year by coastal wetlands in Louisiana with the energy equivalent of fisheries harvested locally in a year. Loss of coastal wetlands each year implies the loss of annual primary production and the cascading loss of secondary production in the coastal food web.
Here’s the reference and abstract:
Bahr, L.M., Jr., J.W. Day, Jr. and J.H. Stone. 1982. Energy cost-accounting of Louisiana fishery production. Estuaries 5(3):209-215.
Abstract – A quantitative relationship between gross primary production and secondary production of aquatic upper level consumers was derived for the inshore portion of the Louisiana coastal zone. We estimate that 1,700 units of gross primary production are required to produce one unit of upper level consumers. Lower and mid-level consumers are estimated to require lesser amounts, 300 and 600 units, respectively. Harvested fishery groups in the inshore ecosystem represent a total average of about 23,000 metric tons (dry wt) or about 1.2 X 1011 Kcal (5.0 X 1011 KJ) annually. This harvest “costs” the system about 7 X 1013 Kcal (3.3 X 1014 KJ) of gross primary production, or an equivalent of 4 X 1014 Kcal (1.7 X 1015 KJ) of fossil fuel.
© 2002. Estuarine Research Federation.
On September 19, 2012 Benjamin Alexander Bloch with The Times-Picayune reported a surprising increase in the menhaden harvest rate in the Gulf of Mexico, this despite the progressive loss of nursery ground area, worsening hypoxia and the Macondo Deepwater Horizon well blowout. Here’s the opening paragraph:
The National Marine Fishery Service on Wednesday released fisheries statistics that show the 2011 seafood catch in the Gulf of Mexico rebounded to its highest volume since 1999. That’s despite the 2010 Deepwater Horizon oil spill that still has fishers fearing less seafood in local waters. Menhaden, often described as a keystone species showing and helping determine the viability of many local species, rose dramatically in Louisiana. It jumped from its 10-year average of about 900 million pounds of catch since 2001 to about 1.3 billion pounds in 2011. Sales of menhaden at Louisiana docks jumped from the $47.9 million average to $100 million.
This article includes a useful breakdown of fishery landings and values, but unfortunately no mention is made of the presumably significant recreational harvest in 2011 and frankly I can’t remember how (or whether) we estimated recreational landings in 1982.
I’d love to hear an informed discussion of the implications of the current fishery harvest and what it tells us about coastal restoration efforts since 1991. Thirty years of delta history have washed under the bridge since 1982 and it would seem useful for those of us who claim an implicit quantitative relationship between the size and state of our coast with fishery landings both now and down the road.
*Residents of Grand Isle and Leeville were exceptions, of course.
DECEMBER THIRD
Cuts to higher education will have coastal costs
Academic science in Louisiana is being systematically undermined by our anti-science governor, which has serious coastal implications that will far outlive his tenure. Koran Addo reported in today’s The Advocate that four successive years of cuts to higher education are having serious negative impacts on the academic climate of the state, with a brain drain underway and a snowballing loss of funding for scientific research as the word spreads.
Defunding the investment in research centers of excellence is giving us a black eye among research institutions with whom Louisiana researchers compete for grant monies. This perfectly complements the damage done by the governor’s promotion of Louisiana’s Science Education Act, which makes us a science laughingstock and encourages our brightest students to go out of state for college..
Considerable tension between coastal scientists and the Jindal administration is not a new phenomenon. The most obvious evidence for this climate happened during the sand berm episode, during which most credible scientists disagreed with the governor’s notion of blocking BP oil with sand piles.
It appears to me that Louisiana coastal officials who need definitive answers to questions about project effectiveness, for example, are consciously going around academic researchers, whose results can’t be controlled, and outsourcing applied coastal studies to private companies, such as the Rand Corporation, CH2MHill, etc. Private contractors are far more likely to provide answers in line with the Governor’s opinion.
Here are some quotes from a November 16 post in Reappropriate
…Jindal has opposed embryonic stem cell research and same-sex marriage, and has gone so far as to support legislation instituting a formal ban of both. Jindal is fervently pro-life (which he credits to his Catholic faith), although he does support exceptions in situations of rape or when they mother’s life is at risk. He supports the teaching of intelligent design in public education.
… it remains unclear to me how Jindal, who is clearly angling to become the new de facto leader of the Republican party and a 2016 contender for the White House, can reconcile his current record (which falls too often on the anti-scientific and anti-intellectual side of many issues) with his recent urging that the GOP reject “dumbed-down conservatism.
DECEMBER SECOND
Gulf Coast Ecosystem Restoration Council hosts first public meetings to solicit feedback on BP recovery efforts under the RESTORE Act.
Signing the RESTORE Act.
Mark Schleifstein reported yesterday in NOLA.com that the Gulf Coast Ecosystem Restoration Council will hold its inaugural meeting in Mobile on December 11. The goal for this meeting, and four subsequent ones across the coast, is to solicit public input on the targeted investment of from $4 to 17 billion in federal fines against BP under the Clean Water Act, as specified by the RESTORE Act. ‘RESTORE’ stands for (Resources and Ecosystems Sustainability, Tourism Opportunities and Revived Economies). How much are we paying folks to come up with such acronyms?
The ultimate goal is to pay for some of the colossal ecological and economic damage done to coastal ecosystems from the release over three months of about 4.1 million barrels of oil, by far the largest such accident in history.
On July 15, 2012 USA Today carried a good description by Ledyard King and Deborah Barfield Berry of the challenge to spend RESTORE Act funds effectively under a process of meaningful cooperation among the gulf states. Based on comparing this July article with Mark Schleifstein’s account on December 1 it sounds as though the planning process leading up to the public meetings has gone smoothly and that no major disagreements among states or agencies will arise.
My political side is cynical but the unusually broad support for the RESTORE Act makes me hopeful that the council members won’t become unduly influenced by provincial thinking and seduced by short-term economic development projects, rather than by long-term efforts to enhance the northern gulf ecosystem. I was heartened to read that an Alabama official named Casi Callaway wants to use some of that state’s money to create 100 miles of linear oyster reefs along the Alabama shoreline.
The USA Today article includes the following account of the breakdown of the funds:
•Thirty percent of the money will be controlled by the 11-member Gulf Coast Ecosystem Restoration Council, which will develop a comprehensive restoration plan. Members include all five governors (or their designees), the secretaries of the Agriculture, Commerce, Homeland Security and Interior departments, the secretary of the Army and the administrator of the Environmental Protection Agency.
•Sixty-five percent of the money will be controlled by state and local governments for such things as tourism, the environment and the economy.
Of that, 35% will be distributed equally among the five states for economic and ecological recovery. The rest will be distributed to the states based on a formula that takes into account factors such as miles of beachfront and population.
•Thirty percent of the money will be controlled by the 11-member Gulf Coast Ecosystem Restoration Council, which will develop a comprehensive restoration plan. Members include all five governors (or their designees), the secretaries of the Agriculture, Commerce, Homeland Security and Interior departments, the secretary of the Army and the administrator of the Environmental Protection Agency.
•Sixty-five percent of the money will be controlled by state and local governments for such things as tourism, the environment and the economy.
Of that, 35% will be distributed equally among the five states for economic and ecological recovery. The rest will be distributed to the states based on a formula that takes into account factors such as miles of beachfront and population.
•The remaining 5% of the fine money will finance research, with half going to the Gulf States Marine Fisheries Commission and half going to a “center of excellence” in each state.
Schleifstein’s article includes the following details about the meeting:
The meeting will be from 1 p.m. to 4 p.m. at the Renaissance Mobile Riverview Plaza Hotel, 64 South Waters St., Mobile, Ala., 36602. The council will hold two open houses Dec. 11, from 11 a.m. until 1 p.m., and from 4 p.m. to 7 p.m., to provide an additional opportunity for members of the public to discuss restoration issues with participating state and federal representatives.
Pre-registration for the council meeting is available on the web.
DECEMBER FIRST
What’s time to a pig and how old is the Grand Canyon?
Some years ago in a Baton Rouge bar I was approached by an acquaintance, a middle school teacher who knew that I had a coastal science background and an advisory position to whomever was governor at that time. My friend “Kenny” asked me about the age and formation of the Mississippi River delta, the Louisiana coast.
I rattled off the orthodox answer, 6,000-7000 years, the number used by all the geologists I know and most of us who discuss saving America’s Delta. That extraordinarily young age is not a guess; it’s based on thousands of core samples collected across the coast beginning in the 1950s and painstakingly analyzed with the standard tools of earth sciences, including the use of radiocarbon and other radioisotopic dating tools.
This research, which yielded information crucial to coastal restoration today, was largely funded by oil companies anxious to find the most fruitful places to drill for hydrocarbons considerably older than the salt domes that had trapped them.
The four dimensional maps* showed that the main distributary of the lower river changed course about every thousand years, abandoning one subdelta lobe and beginning the formation of another. At about this point Kenny was bored and he asked me about the Grand Canyon.
He caught me off guard with the question, way beyond my geological comfort zone. Anyhow I explained that the Grand Canyon is so much older than coastal Louisiana as to represent a different category of science that deals with continental drift (plate tectonics)…in time spans ranging from millions to billions of years. I told Kenny that the canyon was carved out over millions of years by the Colorado river, a mile down and still doing its thing (with a lot less power, thanks to man).
At that point he scratched his head and said that he understood that the Grand Canyon was formed during the biblical flood that induced Noah to build his ark. That would make it perhaps four thousand years old, perhaps 2/3 the age of our coast.
I tried to keep a straight face while mentioning the presumed old world location of Noah’s Flood and the volume of sediment that would have had to be scoured away in merely forty days and forty nights. The conversation ended there, unresolved, but I was reminded of the occasion when I heard Melissa Block and Robert Siegel joined forces to interview Joel Achenbach on NPR’s All Things Considered (ATC) yesterday about a raging new geological controversy…the age of the Grand Canyon!
It seems that an ‘upstart’ geologist named Rebecca Flowers, Ph.D., is presenting a paper at a major scientific conference next week in San Francisco…the American Geophysical Union…in which she will state that the canyon is over ten times older than previously believed, 70 million years. In other words, dinosaurs could have roamed the bottom of the canyon as it was then..
If you don’t think that’s surprising, it turns out that the age of this magnificent formation is thought by a grand old man of geology, Carl Carlstrom, Ph.D, to be less than 6 million years. Dr. Carlstrom will be in the meeting room and I’d sure love to be a fly on the wall.
I can hear Kenny now saying, “what about that, ‘scientist’?”
I couldn’t resist closing this mini-post with a videoclip in Slate.com in which Pat Robertson, televangelist, one time presidential candidate and former young earth creationist, now acknowledges that the Earth is older than 6,000 years. Go Pat!
*Including time, as well as the three Cartesian coordinates.
Wow I didn’t know you could also see into the future! Can you pass on some lottery numbers for me?
“Since April 20, 2020″ hehe
Len,
Re fishery thermodynamics, it’s not that complicated, really. First, these are landing data, so the first thing one should ask is whether changes in fishing effort are responsible. Second, keep in mind that, as summarized in the TP article, the higher total volume of landings in 2011 is due to menhaden—1.3 billion pounds of the 1.5 billion pounds for all species, compared to 900 million pounds for menhaden for the 10 year average. In fact, landings of oysters, white shrimp and brown shrimp in 2011 were 12, 18 and 10 % lower, respectively, than the ten year averages. Third, pelagic species that live and feed on plankton in surface waters, such as menhaden, are well known to increase their biomass and fishery yields under anthropogenic nutrient enrichment, even when it produces seasonally recurrent hypoxia, such as has developed on the Louisiana shelf over the last 40 years. Twenty years ago Caddy (1993), cited in the Cowan paper, presented a compelling synthesis showing this in contrast to the effects on demersal populations negatively affected by hypoxia. No need to invoke vague theories of energy efficiency or ecosystem stability.
The scale of restoration is the challenge. To neutralize and potentially reverse the shift in ecological baseline that is happening along the coast (which, as I read Dr. Cowan et al’s. paper, has not yet reduced post-1930 fishery production and may/may not manifest in fisheries “collapse” for additional human generations), it will take thinking, planning and executing on a scale commensurate with the delta system. Not sure that the SMP acheives that. In the meantime, and with some trepidation about the ultimate impacts of the oil spill on marine organisms, when the wind lays the fishing has been good.
BULLETIN OF MARINE SCIENCE, 83(1): 197–215, 2008
Bulletin of Marine Science 197
© 2008 Rosenstiel School of Marine and Atmospheric Science
of the University of Miami
MOTE SYMPOSIUM INVITED PAPER
LIFE HISTORY, HISTORY, HYSTERESIS, AND HABITAT
CHANGES IN LOUISIANA’S COASTAL ECOSYSTEM
James H. Cowan, Jr., Churchill B. Grimes, and Richard F. Shaw
ABSTRACT
Perhaps the most perplexing aspect of the highly engineered and artificial Mississippi
River deltaic ecosystem is lack of evidence that fish production has decreased.
Louisiana accounts for ~75% of the fishery landings in the U.S. Gulf of Mexico and
60%–80% of the nation’s total annual coastal wetland loss, the human-caused reasons
for which are well documented. Continued alteration, degradation, and loss of
Louisiana’s estuarine and wetland habitats makes knowledge of the relationship between
habitat stability, and its effects on nursery-ground function and fish production,
critical. As a result of this issue in Louisiana and elsewhere, concepts of ecosystem
management and sustainable development have become part of state, national,
and international dialogue about adaptive environmental management. Formulation
and implementation of long-term, sustainable coastal policies and integrated
management strategies demand a better understanding of (1) habitat and ecological
stability and associated functional responses to both episodic and chronic insults,
especially given the limited vitality of already-stressed coastal ecosystems, and (2)
the compounding and complex effects of multiple impacts superimposed on issues
associated with shifting baselines and climate change.
A number of investigations have demonstrated relationships between fisheries
yields and the high nutrient loads, freshwater inputs, shallow depths, large areas
of tidal mixing, coastal vegetated area, surface area of lagoon-estuarine systems,
and resulting high productivities that are typical of estuaries and estuarine plume
ecosystems (see Deegan et al., 1986; Nixon, 1988; Iverson, 1990; Sánchez-Gil and
Yáñez-Arancibia, 1997; Yáñez-Arancibia et al., 2004). As a result of these relationships,
and despite the small aggregate spatial extent of estuaries ( 30% per day in weight) and biomass production
that result from very high consumption rates (Tyler and Gallucci, 1980; Deegan,
1986, 1990; Cowan and Houde, 1990; Deegan et al., 1990; Houde and Zastrow, 1993),
but factors hypothesized to increase abundances of young fishes in estuaries—such
as (1) retention of fish in certain areas within an estuary as a result of physical processes;
(2) physical concentration of fish in a system as a result of a net positive flux
of individuals from other areas; and (3) concentration through differential survival
of individuals in areas of high productivity and/or low predation such that ratio of
instantaneous growth in weight (G) to instantaneous mortality rate (Z) is maximized—
are not well documented in estuarine nursery habitats along the northern
Gulf (Lyczkowski-Shultz et al., 1990; Beck et al., 2001). This situation is exacerbated
because many of the physical processes usually invoked—e.g., two-layered circulation
resulting from strong tidal forcing, suggested as an important factor in more
comprehensively studied, temperate estuaries—are not as evident and cannot be
assumed to play a role in the shallow estuaries of the northern Gulf. The estuarydependency
paradigm may therefore not apply as well to fishery systems in the Gulf.
We contend that high fisheries production may be attributable in part to estuary-like
conditions that cover large portions of the inner continental shelf during high river
discharge periods, because relatively few fish species are wholly adapted to life cycles
within lagoon-estuarine systems. Moreover, in the subtropics and tropics of the Gulf,
and especially in areas where high river discharges lead to estuary-like conditions on
the shelf, the distinction between estuaries and the shallow shelf is clearly smaller
than in other areas (Pauly and Yáñez-Arancibia, 1994; Yáñez-Arancibia et al., 1994;
Yáñez-Arancibia, 2003). Even if continental shelf populations in most estuarine regions
are strictly estuary dependent (Longhurst and Pauly, 1987), they may not be in
Gulf areas characterized by soft-bottom communities on the inner shelves subject to
high river discharge (Deegan et al., 1986; Pauly, 1986, 1998; Pauly and Yáñez-Arancibia,
1994; Sánchez-Gil and Yáñez-Arancibia, 1997; Baltz et al., 1998; Chesney et al.,
2000; Lara-Dominguez, 2001; Yáñez-Arancibia, 2003).
Disentangling the relative contributions to fish production by estuarine and estuary-
like inner shelf ecosystems may be key to long-term resource management,
especially in light of rapidly changing conditions. For example, the Mississippi River
delta is a complex and unique ecosystem including vast areas of water and wetlands
(~15,000 km2 of wetlands alone) in which the rate of land loss has reached catastrophic
proportions. Within the last 50 yrs, loss rates have exceeded 103 km2 per
year, and in the 1990s the rate has been estimated to be between 65 and 90 km2
each year. The totals represent 80% of the coastal wetland loss in the continental
United States. The reasons for wetland loss are complex and differ in different areas
across the state. Since the scale of the problem was recognized and quantified in the
1970s, much has been learned about the factors that change marshes to open water
and cause barrier-island fragmentation and submergence. The effects of natural processes
like subsidence and storms have combined with human actions at large and
small scales to produce an ecosystem that may be on the verge of collapse. If recent
loss rates continue into the future, then by 2050, despite current restoration efforts,
coastal Louisiana will lose more than 250,000 additional hectares of coastal marshes,
swamps, and islands. The loss could be greater, especially if worst-case scenario
projections of eustatic sea-level rise are realized, but in some places nothing remains
to be lost. Lost with these wetlands will be the functions and values associated with
them: commercial harvests of fishes, furbearers, and alligators; recreational fishing
and hunting; ecotourism; habitats for threatened and endangered species; waterquality
improvement; navigation corridors and port facilities; flood control, including
hurricane protection; and the intangible value of land settled centuries ago and
passed down through generations. The public-use value of this loss is estimated to
exceed $37 billion by 2050 (LCWCRTF, 1998; NRC, 2006a).
As a result, the target of understanding ecosystem function (including fishery ecosystems)
may be a moving one, as large-scale and rapid changes in fish habitat (some
of which are man-induced) occur against the backdrop of longer-term changes attributable
to a variety of human-caused insults, climate change, and natural delta
cycles (Kennedy et al., 2002; NRC, 2006a; Caddy, 2008). Nevertheless, we will continue
the effort, focusing initially on the Mississippi River plume/shelf ecosystem,
recognizing fully that fish production in the northern Gulf may be inexorably linked
to the fate of coastal wetlands.
Physical Setting.—Perhaps the most characteristic feature of the Louisiana
continental shelf region is the presence of two major sources of fresh water, the Mississippi
and Atchafalaya rivers, that strongly influence the physics (Wiseman et al.,
1982), biology (Hanson, 1982; Wiseman et al., 1986), and chemistry (Ho and Barrett,
1975) of shelf waters. The Mississippi’s discharge (18,400 m3 sec–1; Milliman and
Meade, 1983) and watershed (3.3 million km2) are the largest in North America. By
mean discharge, the Mississippi is the sixth largest river in the world. Levees confine
the river channel for 3500 km upstream from the coast, and diversions are being
implemented to combat coastal erosion in sediment-starved deltaic estuaries. The
river’s delta is a complex system that encompasses 40% of U.S. total coastal wetland
area. Freshwater runoff from the combined rivers contributes to a low-salinity, highly
turbid, near-shore water mass or plume within a westward flowing coastal current
(CC), which is constrained within a steep, horizontal, salinity front on the mid-shelf
about 20–50 km offshore (Crout, 1983; Cochrane and Kelly, 1986).
Wiseman et al. (1986) described several biological and chemical associations along
the salinity front on the outer edge of the CC west of the Atchafalaya River in winter
and early spring 1981–1982. High concentrations of nutrients (primarily nitrate and
silicate) are carried to the shelf by the riverine plume, producing areas of high primary
productivity and elevated zooplankton biomass along the offshore edge of the CC
on the mid-shelf. Moreover, the rivers are the major nutrient source for the northern
Gulf, and their combined nitrogen loadings support pelagic primary production on
the entire Louisiana continental shelf (106,866 km2) with an estimated recycling rate
of 3.7 yr–1 (Justic et al., 1993). The “new” river-supplied nutrients quickly become
depleted along the salinity gradient downstream from the river plume. Primary production is then supported by regenerated nutrients for “great distances from the river
mouth” (Rabalais et al., 1996, 2002, and papers cited therein), but peak primary production
in surface waters downstream of the Mississippi River plume appears to lag
one month behind peak river discharge (Justic et al., 1993). Significant gradients in
surface chlorophyll (indicative of the CC and plume) have been observed downstream
and across shelf as far west as 95.0°W on the Texas-Louisiana shelf in April and October;
highest values are seen in April immediately downstream of the plumes and
along the shoreward edge of the CC (Rabalais, 1993; Rabalais et al., 2002).
Recruitment.—A convenient way of thinking about fish production is that production
equals growth (the increase in biomass of individuals in the population) and
recruitment (the addition of new individuals after successful reproduction and survival
to enter the population) minus natural and fishing mortality. Of the first two,
recruitment through early life is widely believed to have the greatest influence on
year-class success (see Cowan and Shaw, 2002, for review). Although resource-rich
feeding conditions in the Mississippi River plume no doubt favor growth, the influence
on recruitment is probably the principal mechanism whereby river discharge
directly affects fish production (see Grimes, 2001, for review).
Waters influenced by the plume are a rich environment where both physical (e.g.,
hydrodynamic convergence, water column stratification and transport, retention of
fish larvae) and biological (e.g., primary and secondary production) dynamics appear
to favor the processes that regulate recruitment, i.e., larval fish feeding, growth, and
survival. Although several hypotheses have been advanced about how recruitment,
especially the near field, close to the river mouths, is affected by the plume (see review
by Grimes, 2001), the most plausible may be the “halo” hypothesis: that the dynamics
of feeding, growth, and mortality in the far field of the discharge plume favor survival
and recruitment of fish larvae (Cowan and Shaw, 1991; Grimes, 2001). In the case
of the Mississippi’s plume, conditions downstream of the river mouths support feeding
and growth better than do average conditions, and mortality is therefore lower
than that near the river mouths. The westward-moving Louisiana CC and eastward
return flow along the shelf (an elongated clockwise gyre, Cochrane and Kelley, 1986;
Walker et al., 2005) move larvae and their prey west along the coast away from the
near-field plume yet retain them on the Louisiana-Texas shelf. Epifanio and Garvine
(2001) describe a similar mechanism that transports yet retains larvae in the Atlantic
Ocean off Delaware Bay. Although the prey field downstream of the plume is not as
rich, or the growth rate of fish larvae as high, as in the near-field plume, the predator
field and mortality rate may be lower, such that conditions are better than average
and adequate to support good larval production.
Some empirical evidence is available for evaluation of this hypothesis, but it offers
only equivocal support. The concentration of copepod nauplii in the far-field plume
off Galveston, TX, is only 10%–20% of that in the near-field plume off the Mississippi
River delta (Dagg et al., 1988; Dagg and Whitledge, 1991), so prey availability
for fish larvae in the far-field plume is not as great as that in the near-field plume,
but at 10 nauplii L–1 the prey concentration may still be adequate to support good
growth and survival of fish larvae (Houde and Schekter, 1978, 1981). Total zooplankton
concentration, which may reflect prey availability, and larval fish abundance remain
high downstream of the near-field plume on the west Louisiana shelf (~2 mg
L–1 and 57 larvae m–2, Cowan and Shaw, 1991). Also in support of this hypothesis are
the findings of Warlen (1988) that growth rates of gulf menhaden larvae were 53%
COWAN, JR. ET AL.: LIFE HISTORY, HISTORY, AND HYSTERESIS IN COASTAL LOUISIANA 201
lower in the far-field plume off Texas than off the Mississippi River delta, but this
downstream growth was still higher than that upstream of the discharge plume off
northwest Florida, where growth was 61% below growth in the river plumes. Not supporting
the growth element of the hypothesis are the findings that Spanish mackerel
[Scomberomorus maculatus (Mitchill, 1815)] and little tunny [Euthynnus alletteratus
(Rafinesque, 1810)] larvae did not grow faster in the river discharge than elsewhere in
the Gulf or Atlantic Ocean (DeVries et al., 1990; Allman and Grimes, 1998). Consistent
with it, however, is that instantaneous mortality rates for the two species were
24 and 50% lower away from the rivers mouths, although the nutrient-rich discharge
plume of the Mississippi River clearly seems to increase fish production, the exact
mechanism through which it does so is unclear. Against that background, an evolving
problem associated with river discharge on the shelf may have important consequences
for future recruitment potential.
Hypoxia.—Although many factors impede understanding of the direct effect that
Mississippi River plume water has on recruitment success, growing evidence indicates
that high levels of primary production on the Louisiana shelf annually contribute
to the formation of a large area of hypoxic (O2 4.0). Pauly and Palomares (2005) attributed this difference to a highly degraded
food web in which the largest predators had long since been removed by fishing. An
alternative interpretation is that the ecosystem supporting Gulf fisheries is so highly
degraded that it can no longer support members of the food web at its apex.
Neither of these interpretations is easily defended solely on the basis of the mean
trophic level index because Gulf fisheries, of which ~75% are landed in Louisiana,
have historically been dominated by gulf menhaden, which consume phytoplankton,
and by penaeid shrimps, which are primarily detritivores (both are assumed to be
estuary dependent). A low mean trophic level index is therefore inevitable for Gulf
commercial fisheries if menhaden and shrimp included. This contention is supported
by the findings of Chesney et al. (2000), who detected only minor changes in the relative
contribution of the species that make up the commercial landings, exclusive of
menhaden and shrimp, and only a slight increase in the relative abundance of species
thought to depend less on coastal wetlands as nursery habitat [e.g., striped anchovy,
Anchoa hepsetus Linnaeus, 1758)]. The latter finding may result, in part, from the
yearly removal of high numbers of demersal fishes (mostly juveniles) as by-catch in
the Gulf shrimp fishery (Fig. 1; see review by Diamond, 2004; Walters et al., 2008).
Although by-catch is clearly declining, the declines could be caused by hypoxia,
technological improvements of the shrimp fleet like turtle excluders and by-catch
reduction measures, declines in shrimp fishing effort, or declines in the abundance
of demersal groundfish stocks. The last is consistent with the interpretation of Pauly
and Palomares (2005).
Why Are Landings Not Decreasing—A Link to Wetlands?—Clearly, we
do not understand how the Mississippi River plume ecosystem directly affects fish
production, exclusive of possible habitat links to coastal wetlands that were created
by the natural delta cycle (Day et al., 2000; NRC, 2006a), though we can speculate
that recruitment is somehow increased by the “halo” effect, a plausible hypothesis
given the obvious high numbers of juvenile estuary-dependent fishes found both on
Figure 2. Louisiana commercial landings. Total area is all species combined. The darker shading
is all landings excluding gulf menhaden. The lighter shading is landings of gulf menhaden (data
from NOAA Fisheries online (http://www.st.nmfs.gov/st1/commercial/landings/annual_landings.
html) the shelf (Fig. 1) and in the estuaries. The life histories of menhaden and shrimp favor
resilience in the face of fishing pressure (Rose et al., 2001; Walters et al., 2008); these
species are essentially annual crops.
The current configuration of the Mississippi River is artificial and represents a
human-induced interruption of the natural delta cycle that began after flood control
measures and farming practices were altered in response to the 1927 flood (NRC,
2006a). It has resulted in ~5% higher flows but has reduced sediment loads in the river
proper and in a river that now discharges far offshore, on the edge of the continental
shelf (Day et al., 2000; NRC, 2006a). Both of these changes have been linked to the
high rates of wetland loss described above, attributable to deprivation of nutrients
and sediments lost to the offshore environment. They, and other changes, have also
probably contributed to the hypoxia problem discussed previously, and have been
punctuated by significant hydrological changes (mostly saltwater intrusion) that began
in earnest with oil and gas exploration in the 1930s and 1940s (LCWCRTF, 1998;
NRC, 2006a).
So why are landings not decreasing? One possibility is that Pauly and Palomares
(2005) are correct, that fisheries production, although still high, reflects food-web
changes that occurred before the period of record. If this is the case, we do not believe
that fishing is the likely cause. Rather, we favor the alternative mentioned above,
that the fisheries of today reflect a degraded ecosystem attributable to environmental
insults that began in the late 1920s. Recruitment is the most obvious link to biomass
and yields, but we have no real evidence that recruitment is now limiting and/or
declining, although we be sure that current levels of recruitment are not lower than
historical highs (and may continue to decline in response to hypoxia on the shelf).
Other factors. some of which have already been discussed, that could contribute to or
obscure the relationship between ecosystem health and changes in fish production
are wetland loss and habitat modification, hypoxia and eutrophication, fishing impacts
and by-catch, and climate change. Unfortunately, all of these factors could have
both negative and positive or neutral effects. For example, consider wetland loss. The
alteration of flow regimes in large river ecosystems and losses of emergent and submerged
aquatic vegetation are a chronic problem worldwide and by no means unique
to Louisiana (Nilsson et al., 2005). Evidence suggests that fishery landings are correlated
with the spatial extent of estuarine vegetation (Deegan et al., 1986; Pauly and
Ingles, 1988; Chesney et al., 2000). “Indeed, the role of these near-shore ecosystems
as nurseries is an established ecological concept accepted by scientists, conservation
groups, managers, and the public and cited as justification for the protection and
conservation of these areas…. The ecological processes operating in nursery habitats,
as compared with other habitats, must support greater contributions to adult
recruitment from any combination of four factors (1) density, (2) growth, (3) survival
of juveniles, and (4) movement to adult habitats …” (Beck et al., 2001: 633–635).
Interestingly, these criteria established by wetland ecologists and managers clearly
echo NOAA’s National Marine Fisheries Service criteria for identifying essential fish
habitat and are consistent with the findings of Caddy (2008), who suggests that the
overall carrying capacity of any coastal marine habitat is determined by the habitat
with the lowest stage-specific carrying capacity rather than by gamete production or
trophic dynamics.
The relationship between fish production (yields) and the loss of marsh habitats is
not clear, however, and we have already shown that Gulf landings appear to be stable,
if not increasing, despite accumulating habitat losses (Zimmerman et al., 1989, 1991).
One potential hypothesis is that marsh edge, i.e., perimeter, is the critical habitat for
many species and that the nursery ground function/value will not decline or result in
reduced landings until the quantity of marsh-edge perimeter declines. During marsh
loss, the amount of marsh edge initially increases and then declines as healthy marsh
is converted to broken marsh and then to open water. The transitory increase in
marsh-edge perimeter that occurs in the marsh break-up phase may mask the immediate
impacts of habitat loss on landings (Browder et al., 1985, 1989). Another related
hypothesis postulates that marsh edge is not the critical habitat per se but serves as
the essential conduit for critical trophic exchanges with the flooded marsh (Zimmerman
and Minello, 1984; Rakocinski et al., 1992; Baltz et al., 1993; Minello et al.,
1994; Caddy, 2008). Marsh loss may therefore actually be having a positive impact,
at least for now.
We have discussed hypoxia, but increased inorganic nutrient inputs have been to
shown to increase fisheries yields as primary productivity is stimulated (Nixon, 1988;
Iverson, 1990) from oligotrophy to mesotrophy, but yields can decline under eutrophic
and/or dystrophic conditions, often rapidly (Caddy, 1993). The latter situation
can also result in increases in abundances of trophic dead ends, such as gelatinous
zooplankton, which prey on fish early life-history stages (Cowan and Houde, 1992,
1993), thus exacerbating the decline.
Fishing impacts have also been discussed, but clearly, if observed declines in bycatch
are attributable to any cause mentioned above other than a decline in groundfish
stocks, the decline can be seen as a positive impact. Of interest, however, are
the findings of Walters et al. (2008), who suggest that recovery of some groundfish
affected by by-catch mortality (e.g., sea catfishes) could increase predation pressure
on, and negatively affect, recreationally and commercially valuable species like red
drum and red snapper. Climate change too can have both positive and negative impacts.
Worldwide, fisheries for penaeid shrimps are highest nearer the equator than
are Louisiana and the northern Gulf (Kennedy et al., 2002), so modest increases in
water temperatures may improve yields in this valuable fishery.
Historically, coastal wetlands in Louisiana have been dominated by Spartina sp.
(and Phragmites sp. in the fresher Mississippi and Atchafalaya River deltas), but recently
black mangroves (Avicennia germinans Linnaeus) have become established
and proliferated along Louisiana’s coastline because a hard freeze, which in the past
could be expected on average every 4 yrs, has not occurred since 1989. Wetland fisheries
ecologists once widely assumed that Spartina and black mangroves provided
equally valuable nursery habitat (Manson et al., 2005) and that primary production
from both habitats was readily transferred to higher trophic levels, but this paradigm
has been seriously challenged. Evidence indicate that mangrove detritus may
not contribute significantly to basal resources and that use by decapods and finfishes
of mangrove habitats may not be equally advantageous across habitat types
and latitudes (Lee, 1995; McIvor and Smith, 1995; Marguillier et al., 1997; Sheridan
and Hays, 2003). The effects of continued expansion of black mangroves on nurseryground
function and fisheries production in Louisiana is therefore unknown.
The Way Forward—Ecosystem Restoration.—Although neither exhaustive
nor a thorough review of the issues identified, the list of contributing factors given
above well illustrates that we may be approaching or have already reached an important
nexus in the history of fish production in the northern Gulf of Mexico
3). Panel A in Figure 3 shows the hypothetical situation in which fish production
remains intact and near historical highs but in which we may be approaching a steep
decline if cumulative impacts reach a tipping point. Panel B shows that in which
Louisiana fish production has already declined below historically higher levels, the
cause of which is overfishing if Pauly and Palomares (2005) are correct. In this case,
the way forward may simply be more conservative fishing regulations. On the other
hand, if either Panel A or B is correct, and declines in production have been (or will
be) attributable to declines in the Mississippi River ecosystem’s ability to sustain recruitment
and/or provide nursery habitat, the way forward may be much more complicated.
Figure 3. The history or, perhaps, future of fish production in Louisiana and presumed causes for
change. Panel A shows the hypothetical situation in which the fisheries remain intact and near
historical highs but that we may be approaching a steep decline if cumulative impacts reach a
tipping point. Panel B shows that in which Louisiana fisheries have already declined below historically higher levels.
Continued alteration, degradation, and loss of Louisiana’s estuarine and wetland
habitats makes knowledge of the relationship between habitat stability and its effects
on nursery-ground function and fishery production critical (Caddy, 2008). As
a result, concepts of ecosystem management and sustainable development have become
part of state, national, and international dialogue about adaptive environmental
management, as emphasized in the President’s Commission Report on the State
of the Ocean, the Pew Oceans Commission Report, and language in the recent Sustainable
Fisheries Act. Formulation and implementation of long-term, sustainable
coastal policies and integrated management strategies demand a better understanding
of (1) habitat and ecological stability and associated functional responses to both
episodic and chronic insults, especially given the limited vitality of already-stressed
coastal ecosystems, and (2) the compounding and complex effects of multiple impacts
superimposed on issues associated with shifting baselines and climate change
(Jackson et al., 2001).
Issues facing Mississippi deltaic ecosystems are not unique, but Hurricanes Katrina
and Rita in 2005, during which more than 560 km2 of coastal marshes were
lost, caused Louisiana to renew its commitment to preserving and restoring coastal
ecosystems in the region by managing the impacts of human activities through the
Coastal Wetlands Planning, Protection and Restoration Act of 1990, Coast 2050,
and Coastal Louisiana Environmental Assessment and Restoration programs. These
initiatives include large-scale freshwater and sediment diversions, use of wetlands
to provide tertiary sewage treatment, proactive management of wetland water-control
structures, and creative mitigation banking involving habitat enhancement and
creation to offset environmental impacts, but the question remains—can we steer a
degraded ecosystem toward some alternate steady state that resembles a historical
baseline?
The restoration activities being proposed in Louisiana will attempt to do just that,
primarily on the basis of the assertion that large-scale reintroduction of Mississippi
River water can significantly shift the ecological baseline back towards prestorm
conditions in the short term and toward less degraded baseline conditions in the
longer term. We recognize the difficulties embodied by this assertion, however. Although
recent research (Day et al., 2003; DeLaune et al., 2003; Mitsch et al., 2005)
has buoyed our confidence in the possibility of restoring degraded wetlands through
large-scale diversions, we understand that fundamental differences in the likelihood
of long-term success depend on overall system behavior. One endpoint of the continuum
of possible system responses to restoration efforts implies that the Louisiana
coastal ecosystem experienced a regime shift when large-scale leveeing began on
the Mississippi River and oil and gas exploration began in earnest. One important
characteristic of regime shifts is that bottom-up processes, such as climate variability,
usually drive them. Resulting changes in species composition, and in primary
and secondary productivity (or by analogy in the case of Louisiana, shifts in the position
of the main Mississippi River distributary mouth), are inherently reversible.
Perhaps the best-studied example of regime shift occurs in the eastern Pacific Ocean
in response to decade-scale variability in the relative position and strength of atmospheric
highs and lows over the north Pacific (i.e., the Pacific Decadal Oscillation).
Large-scale climate variability produces bottom-up changes in coastal ecosystems
such that, during cold regimes, anchovies are favored, and during warmer periods,
sardines replace anchovies as the dominant forage species in Pacific Ocean ecosystems (Belda, 1999). Characteristic of regimes is that after each shift, the ecosystem
reverts to an alternate steady state, followed by a recovery of the system to near its
state before the change in climate. If the Louisiana coastal ecosystem responds to
restoration as has the north Pacific to climate variability, restoration efforts may produce
a nearly linear response in recovery of ecosystems goods and services, including
fish production (Jones and Walters, 1976).
Another endpoint involves the possibility that restoration of the Louisiana coastal
zone will be more challenging. Several recent studies have shown that human-induced
changes in ecosystem function result from top-down effects such as fishing,
habitat modifications, pollution, eutrophication, etc., and ultimately cause a shift in
the ecological baseline (Jackson et al., 2001). In such cases, the ecosystem alterations
are often much less reversible, for a variety of reasons ranging from reductions or
changes in habitat to reorganizations of food-webs as a result of the removal of top
predators (NRC, 2006b). Regardless of the mechanisms, however, alternate steady
states that have been caused by forcing from the top down may be less likely to return
to a state that resembles “pristine” and thus less likely to provide ecological goods
and services and fisheries production similar to those of predisturbance conditions
(Jones and Walters, 1976).
Perhaps the most notable example of a large-scale shift in the ecological baseline
of a fisheries ecosystem occurred on Georges Bank in response to long-term overfishing
of groundfish stocks (Rosenberg et al., 2005). Because of extreme top-down
forcing attributable to both fishing pressure and habitat alterations from bottom
trawling, the Georges Bank food web reorganized itself, and the more desirable gadoid
groundfish complex was replaced by elasmobranches. Despite a > 10-yr reduction
in fishing pressure, the Georges Bank fishery has failed to recover overall, although
the level of recovery is highly species specific (haddock show recent increases in re-
Figure 4. A hysteresis loop wherein some components of an ecosystem fail to respond through
time as expected, delaying recovery despite a decrease in stress (from J. Steele, pers. comm.).
Hysteresis occurs when ecosystem constituents increase rapidly when stress is low (1), reach a
stable steady state when available resources are fully used or as ecological stressors increase
through time (2), and subsequently collapse when stress becomes excessive (3). Some components
of the ecosystem will then fail to recover even (4) as ecological stress decreases.
cruitment, whereas cod remain depressed; Fogarty et al., 2001), illustrating another
important aspect of baseline shifts.
In highly degraded systems, species-specific variability in the rate of response to
restoration efforts is not uncommon (NRC, 2006b). Some species, or even groups of
species, exhibit hysteresis and do not respond to management as expected. As illustrated
in Figure 4, they may increase rapidly when stress is low, reach a stable steady
state, and subsequently collapse when stress becomes excessive. As suggested by the
Georges Bank example, some components of the ecosystem may then fail to recover
even as ecological stress decreases. The question therefore becomes, “Will the Louisiana
coastal ecosystem and its related fish production respond to restoration efforts
as if the region has experienced a regime shift or a shift in the ecological baseline?”
Is the distinction important?
We contend that this distinction speaks directly to whether our coastal ecosystems
can or cannot be restored and their fish production held intact or increased.
Moreover, answers to these questions are fundamental to understanding the relationships
between fish and coastal habitats and can only be answered if studies of
wetlands function are explicitly linked to their the wetlands’ value as fish habitat and
their role in defining population bottlenecks (Caddy, 2008).
We have reason to be optimistic even though we expect some components of the
ecosystem, particularly higher trophic levels, to recover more slowly then others as
wetlands are restored (Rozas et al., 2005). Our optimism is based on the premise
that the current degraded condition of Louisiana’s coastal wetlands, although driven
by man’s activities from the top down, represents changes that mimic a natural and
short, < 100-yr interruption in a cycle of delta creation/decay that normally takes
1000s of years to complete. Large-scale restoration efforts to divert Mississippi River
water back into degraded areas should therefore begin the delta cycle anew and facilitate
the “resetting” of prior conditions. This premise also implies that to delay restoration
efforts could have important consequences for the likelihood and expected
rates of ecosystem recovery.
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Addresses: (J.H.C., R.F.S.) Department of Oceanography and Coastal Sciences, Louisiana
State University, Baton Rouge, Louisiana 70803-7503. (C.B.G.) Santa Cruz Laboratory, Southwest
Fisheries Science Center, National Marine Fisheries Service, 110 Shaff er Rd., Santa Cruz,
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