![]() Sandro Contenta Top marine scientists are denouncing Canada’s management of fish stocks as a commercially driven approach threatening to wipe out species at risk. The attack comes from two senior members of the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) — the body mandated by federal law to advise the government on species at risk. They note the federal government has consistently refused to list several endangered fish under the Species at Risk Act, which would make their fishing or trade illegal. They include Atlantic cod, cusk and porbeagle shark. During the act’s 10-year history, “there has not been a commercially exploited fish — assessed as endangered or threatened — that has been included on that list,” says Jeffrey Hutchings, a biology professor at Dalhousie University and member and former chair of COSEWIC. Commercial interests always trump ecological ones, Hutchings charges. A stark example, he insists, is the porbeagle shark, whose population has declined by at least 85 per cent since the 1960s. It was assessed by COSEWIC as endangered in 2004. The government refused to list it as a species at risk because a handful of Canadians were fishing it. Today, a dozen fishermen have licences to fish porbeagle in the Atlantic. No one used the licence to fish them this year and only one fisherman did so in each of the last two years. Yet Canada, which fishes more porbeagle than any other country, was roundly criticized last month for blocking a European proposal at an international conference that would have ended porbeagle fishing. “Our (international) reputation is very poor,” says Alan Sinclair, a COSEWIC expert on fish populations who retired from the federal Department of Fisheries and oceans three years ago. “We used to be a leader internationally in conservation and protecting our fish resources back in the 1970s and ’80s,” he adds. “Now people look at us and I’m sure they shake their heads and wonder what the heck is going on in Canada.” Frustration hit a boiling point when Canada pushed for an increase in the bluefin tuna fishing quota at a meeting of the International Commission for the Conservation of Atlantic Tunas(ICCAT) in November. At the same time back home, the government was consulting Canadians on whether to list bluefin tuna as a species at risk, a process triggered by COSEWIC’s 2011 assessment of bluefin as “endangered.” “This risk level,” the government consultation document notes, “indicates that the species is likely to become extinct or extirpated in parts of its range unless something is done to address the threats it is facing.” (Extirpated means found in the wild somewhere, but not in Canada.) Sinclair and Hutchings point to Canada’s tuna quota push at ICCAT to insist the federal government has already made up its mind: “They won’t list the bluefin,” Hutchings says flatly. Listing a species under the act would oblige the federal government to set targets for recovery. It hasn’t even done that for Atlantic cod, Hutchings says, despite the collapse of the stock in the early 1990s. COSEWIC concluded certain types of Atlantic cod were threatened or endangered in 2003 and found them in even worse shape in 2010. Also in worse shape is cusk, a slow-moving member of the Atlantic cod family. COSEWIC, which includes experts from the federal, provincial and territorial governments, described cusk as threatened in 2003. The federal government, citing scientific uncertainty, didn’t list it. In mid-December, the latest COSEWIC report predicted an even bleaker future for the fish, assessing it as endangered. Jean-Jacques Maguire, who spent 20 years as a scientist in the fisheries department, many of them heading the research division, cautions that COSEWIC assessments “are not gospel.” Still, when it comes to setting recovery targets, Canada lags internationally. “We’re not ahead of the game,” says Maguire, who left the department in 1996 and now works as an international fisheries consultant. “The U.S. has a considerably more strict management system.” Faith Scattolon, regional director of Fisheries and Oceans Canada in the Maritimes, insists that Canada’s management of fish stocks is based on peer-reviewed scientific advice. Porbeagle fishing quotas have been slashed. Cusk hasn’t been commercially fished since 1999 and “bycatch” quotas — the amount fishermen can land by mistake — have been cut to 650 tonnes from 900 tonnes annually. Scattolon headed Canada’s November delegation at ICCAT, a commission of 48 countries and the European Union. ICCAT assesses the size of the Atlantic tuna stock, projects its future health, and sets annual fishing quotas. It rejected Canada’s proposal to boost the annual bluefin quota in the western Atlantic to 2,000 tonnes from 1,750. (For the eastern Atlantic and Mediterranean, the total allowable catch for 2013 was set at 13,500 tonnes.) “We’re certainly disappointed with the approach that Canada took at this meeting,” says Amanda Nickson, director of tuna conservation for the PEW Environment Group, a nonprofit conservation group based in Washington, D.C. “Canada was out of step.” Bluefin tuna is highly prized, especially in Japan, with international prices as high as $1,000 a kilo. In Canada, there are 777 people with bluefin fishing licences. They caught 483 tonnes in 2012 — Canada’s share of the ICCAT quota. Catches are mostly by rod and reel and restricted to one per person each year. (Seventy-eight swordfish licence holders can also keep bluefin tuna they happen to hook on long-lines.) Even the government’s toughest critics describe Canada’s bluefin fishery as tightly controlled and monitored. The annual value of bluefin tuna caught runs from $8 million to $10 million, according to federal officials. Most of the catch is in the Gulf of the St. Lawrence and around the Atlantic provinces. The largest portion of Canada’s quota — 30 per cent — goes to fishermen in Prince Edward Island. Michael McGeoghegan, president of the PEI Fishermen’s Association, says his group pushed the government to request a bigger bluefin quota. Tuna numbers are healthy, he says, and fishermen venture no more than 20 minutes from shore before quickly hooking one. “There would be more money in it if we could catch more than one fish,” he says. In its May 2011 report, COSEWIC used ICCAT numbers to put the population of mature bluefin tuna in the western Atlantic at about 65,900 – a decline of 69 per cent since the 1970s. It describes continued overfishing as the largest threat to the species and notes it’s unclear how the massive Deepwater Horizon oil spill in the Gulf of Mexico, where western bluefin spawn, will impact birthrates. Scattolon doesn’t dispute COSEWIC’s figures. But she notes that stocks have been relatively stable since the mid-1980s. And she insists the outlook is good. The last few years have seen a clampdown on illegal bluefin tuna fishing in the eastern Atlantic. As stocks rebuild in the east, so will those in the west because a portion of the Atlantic population mixes, Scattolon adds. Scattolon insists the 2,000 tonnes Canada wanted to fish would have allowed the bluefin population to increase over time. ICCAT scientists don’t agree. Their assessment report in September states that fishing 2,000 tonnes a year, under the scientific scenario most favourable to Canada’s proposal, would not increase the population by 2019 — the target end date for ICCAT’s 20-year stock rebuilding program. Predicting future bluefin populations is a guessing game. Scientists use two scenarios: the “high recruitment” one is based on a common-sense prediction — the more tunas mature enough to spawn, the more baby tunas produced. Those who embrace this scenario argue for less fishing. The “low recruitment” scenario instead argues that environmental conditions, including limited amounts of food, restrict the number of baby tunas that survive no matter how big the spawning stock. So you may as well fish more adult tuna because leaving them to spawn won’t make a difference. “We don’t have the data to say which hypothesis is the correct one,” says Maguire. “You go on faith.” ICCAT will be setting up workshops with scientists and government officials to try to resolve what Scattolon calls the recruitment “conundrum.” Until then, critics say Canada should err on the side of caution. In Canada, Hutchings doesn’t see stock management improving until Canadians become better informed about what he describes as a dire state of affairs. “There are few if any political costs in this country to making bad ocean management decisions,” says Hutchings, who recently chaired the Royal Society of Canada’s expert panel on marine biodiversity. “If there were political costs, we wouldn’t see these types of decisions being made on an almost routine basis.” Source: http://www.thestar.com/news/insight/article/1307961--scientists-fear-canada-will-fish-bluefin-tuna-and-other-species-to-extinction#.UOONCLnq_S0.facebook
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![]() Por Miprv.com Un grupo de jóvenes universitarios se mantiene en vigilia en lo que aseguran es “el último bosque de mangle urbano del pueblo de Dewey en Culebra”, el cual se encuentra amenazado por el desarrollo de un hotel que incluye un estacionamiento subterráneo. Hace unos días fue demolido el Taller Arte Fango, un popular sitio de reunión para la comunidad ubicado en esta área en el corazón del pueblo de Culebra. Allí con frecuencia se congregaban turistas y locales para tocar tambores y disfrutar de experiencias culturales. Los estudiantes se responsabilizaron “por ocupar el mangle urbano con fines de protegerlo de ser posiblemente talado y destruido por San Ildefonso Development, para construir una hostal de tres niveles y un estacionamiento en plena zona marítimo terrestre sin los debidos permisos”, informaron en un comunicado. La zona marítimo terrestre se define como aquella parte de la costa que es sensible a las mareas en su flujo y reflujo del agua; en este caso, las aguas estuarinas del Canal Lubina. Según la politica pública ambiental del Estado Libre Asociado, esta zona se considera un bien de dominio público. Por tal razón, el bosque de mangle urbano no se puede talar, ya que esto alteraría la dínamica del ecosistema y de las aguas aledañas. Las aguas estuarinas en donde se encuentra el mangle son aguas territoriales de los Estados Unidos y el cuerpo de ingenieros tiene jurisdicción para velar que no se altere por ningún tipo de proyecto. “Al destruir los mangles y construir, no habrá un ecosistema para filtrar todas las aguas de escorrentías que genera la zona urbana de Culebra. Por ende, el talar los mangle provocaría una posible obstrucción al canal Lobina por continua deposición de sedimento y pondrá las aguas navegables de los Estados Unidos en un estado suceptible a cambios”, indica el comunicado enviado por los estudiantes. “Por los ecosistemas naturales de Culebra, como también por la vida marina que habita en la zona de mangle y zonas adyacentes como los arrecifes de coral, hemos decidido apoyar a los culebrenses, ocupando el mangle para protegerlo y concienciar a la comunidad sobre el gran valor ecológico que este tiene para el pueblo. La conservación y protección del mangle rojo urbano en Dewey, el cual alberga desde reinitas, zumbadores hasta coquis churri, arañas y cangrejos de mangle será nuestro lugar de estudio, y laboratorio natural, en los próximos dias”, aseguran. “Como universitarios, solicitamos que el equipo de desarrolladores del proyecto Puerto Baia, como también a las agencia pertinentes, que realicen el debido procedimiento de permisos para la construcción. Se solicita que se respeten los procedimientos legales, la política pública ambiental del ELA y a la constitución del ELA; que se haga un deslinde de la zona marítimo terrestre, se evalue si la construcción tendrá impacto ambiental significativo, y que se redacte una Declaración de Impacto Ambiental”. Como parte de la comitiva para poder proteger el mangle rojo urbano, los estudiantes tomarán datos científicos sobre el área y varios censos de fauna y realizarán talleres de siembra de mangle para las posibilidades de comenzar un proyecto de rehabilitación. “Es esencial comenzar un programa de siembra de mangle ya que la zona ha sido altamente impactada en los últimos años y, últimamente, ha enseñado excelentes señales de supervivencia”, informaron. “Es deber de la comunidad puertorriqueña establecer iniciativas para alcanzar el desarrollo sustentable en los diversos aspectos. Debemos vivir e armonía y llevar un balance con el medio-ambiente lo mas sostenible posible. Es nuestra responsabilidad como ciudadanos velar y fiscalizar por el uso sostenible de los recursos naturales y por la conservación de la naturaleza. Hay que tomar acción por lo que tenemos, para que en un futuro, nuestros hijos y nietos puedan disfrutarla en el mismo o inclusive mejor estado”, concluye el comunicado. Haz click para leer una poesía escrita por una de las estudiantes que participa de la protesta pacífica. Ver más fotos y video Recurso: http://www.miprv.com/universitarios-ocupan-mangle-en-culebra-para-protegerlo/ ![]() Quito (AFP). La pesca industrial de arrastre quedó prohibida desde hoy en Ecuador al considerarse que tiene un impacto negativo en el medio ambiente, indicó el gobierno. La prohibición excluye a la pesca de camarón mediante ese sistema, ya que según las autoridades la actividad tiene un menor impacto ambiental aunque deberá cumplir nuevas normas como delimitar la zona de pesca y aumentar el período de veda. En Ecuador hay alrededor de 107 embarcaciones que practicaban la pesca de arrastre, sumando unos 1.000 tripulantes, según el ministerio de Agricultura. El ministro de Agricultura, Javier Ponce, señaló que los propietarios de unas 70 naves que capturaban langostino plantearon su interés en reestructurar las embarcaciones ante la prohibición, que en principio debía entrar en vigor en octubre último. En septiembre pasado, el presidente Rafael Correa declaró que esa actividad tiene un impacto negativo en el medio ambiente y que resta recursos del mar a los pescadores artesanales. El gobierno ofrece créditos de hasta 20.000 dólares para adaptar a las embarcaciones a otro tipos de pesca como de bacalao y compensaciones económicas a las tripulaciones. Se trata de una medida que busca "alternativas posibles para minimizar el impacto de una actividad lícita, pero ambientalmente indeseable", indicó el mandatario. Recurso: http://www.nacion.com/2012-12-15/Mundo/La-pesca-industrial-de-arrastre-queda-prohibida-en-Ecuador.aspx ![]() Manatee (U.S. Fish and Wildlife Service / December 14, 2012 By David Fleshler, Sun Sentinel A conservative legal foundation filed a petition with the federal government Friday to strip the manatee of its status as an endangered species, challenging protections that have prevented the construction of docks and led to slow-speed zones along Florida's rivers and canals. The Pacific Legal Foundation, a California-based organization with a Florida office in Stuart, says the manatee's status should be altered from "endangered" to "threatened," a change that would not result in any immediate decline in protection. But the foundation said it could be a step toward removing it from the protected list completely, reflecting its increase in numbers. The foundation represents Save Crystal River Inc., a group of Citrus County business owners who oppose federal restrictions, which they say harms the local economy. Alan DeSerio, managing attorney of the foundation's Stuart office, said a 2007 review by the U.S. Fish and Wildlife Service found the manatee's prospects had improved to the point that it no longer met the endangered standard. But the agency took no action. "To hold the species in the category of endangered when it's really not, they're not doing their job," DeSerio said. Ultimately, he said, his group would like to see the manatee removed from the list. "Given the rebound of the manatee in Florida, eventually the population could no longer qualify for being threatened," he said. The foundation focuses on environmental regulations, land-use, economic freedom and opposition to race-based government programs. Pat Rose, executive director of The Save the Manatee Club, said the species faces serious threats to its survival, such as the decline of natural springs and high annual body counts from collisions with boats. He called the Pacific Legal Foundation "an organization with deep pockets that's anything but sensitive to the environment, with a major anti-protection agenda." Ken Warren, spokesman for the U.S. Fish and Wildlife Service, said the service will decide within 90 days whether the petition merits a detailed review, then study the issue for a year before announcing a decision. dfleshler@tribune.com, 954-356-4535 Source: http://www.orlandosentinel.com/fl-manatee-endangered-petition-20121214,0,236930.story ![]() By Janet Raloff Welcome to the new climate; it’s keeping those Weather Channel reporters pretty busy with field reports on everything from a crop-slaying U.S. drought to windy deluges and coastal floods. Without question, 2012 ushered in wild and worrisome weather across the planet. The year was among the 10 hottest on record and included a surprising number of record-hot days. Climatologists refer to such events as extremes, and new analyses show that global warming is behind an uptick in some, albeit not all, kinds of extreme events. The strongest evidence has emerged in Earth’s surface temperatures. Two analyses published this summer documented a shift toward hotter temperatures that seemed to kick off around 1981 (SN: 9/8/12, p. 10). Neither of those studies attempted to prove a link to global warming, but other analyses looking at notable 2011 events did probe for such a connection — and in July 2012 indicted climate change for exaggerating most of these events (SN: 8/11/12, p. 14), including Texas’ epic heat wave (shown). The heat had been aggravated by the state’s worst drought in recorded history (SN: 11/17/12, p. 22). In 2012, most of the rest of North America began desiccating. By the end of August, moderate to extreme drought savaged almost two-thirds of the contiguous United States. From January through early December, the United States saw nearly 33,000 new record high temperatures. A stable climate sets as many record highs as lows in a typical year. But record hot days outnumbered record cold ones by about 5 to 1 during that period, in line with a trend of increasing highs relative to lows that has been going on since the 1980s. And then there was the unprecedented melting of the Arctic Ocean’s ice cover. Since 1979, the extent of sea ice at summer’s end has fallen by 13 percent per decade. What remains is also getting thinner (SN: 10/6/12, p. 5). This year’s September minimum plummeted to 3.41 million square kilometers (1.32 million square miles) — about 20 percent below the previous record, set in 2007. As for Hurricane Sandy, it’s not clear whether global warming helped fuel the storm’s power or set up the high-pressure system over Greenland that turned it landward. Despite maxing out as only a Category 2, Sandy devastated Haiti and part of the eastern U.S. seaboard. Data indicated that rare meteorological conditions in the Caribbean and eastern Atlantic combined to spawn a once-in-a-lifetime hybrid superstorm: part hurricane and part nor’easter (SN Online: 10/31/12). Source: http://www.sciencenews.org/view/feature/id/347004/description/Climate_change_goes_to_extremes Un grupo de vecinos de la zona norte protege al tinglar.
Por Myrna Vázquez Rivera En las costas de Arecibo y Barceloneta, un grupo de ciudadanos cuida con celo a un habitante especial y la razón la llevan por nombre: “Yo amo el tinglar”. Se trata de una iniciativa de conservación que lleva a cabo el Comité Arecibeño por la Conservación de las Tortugas Marinas, Inc., mediante la cual este grupo de voluntarios organizados vigilan un tramo de la costa norteña con la tarea de documentar y proteger la actividad de anidaje de las tortugas. Este año, la vigilancia y protección se extendió hasta las playas de Hatillo, gracias a la iniciativa de vecinos preocupados por el anidaje de las tortugas en esa zona. Y es que estas playas se han identificado como un hábitat de máxima importancia para la preservación de tortugas como el Carey, el Peje Blanco, y el Tinglar que está en peligro crítico de extinción. La educación juega un rol fundamental para la organización que ofrece conferencias a escuelas, comunidades y a grupos que visitan las playas, para minimizar los riesgos que ponen en peligro la supervivencia del Tinglar. “La importancia mayor de este proyecto es la educación, llegar a la mayor cantidad de personas para que conozcan nuestro trabajo y que más personas de otros pueblos del litoral costero de toda la Isla se unan”, explica Rosa Mastache, coordinadora de la iniciativa. La organización, que no posee un local desde donde dirigir sus esfuerzos, ha identificado un antiguo Head Start que desean adquirir para desarrollar el museo del Tinglar, un área para ofrecer talleres, conferencias y desarrollar sus esfuerzos de una manera más formal. “Necesitamos un lugar donde reunirnos y llevar a cabo las charlas, hacer un centro de información y hasta un museo” expresó Myrna Concepción Torres, también coordinadora del proyecto, que reclama que “aún hay gente que no conoce que hay vida en esta arena”. Los voluntarios recorren diariamente las playas de la zona en busca del rastro de tortugas marinas que les indican el inicio de la temporada de anidaje, que comienza en marzo y se extiende hasta julio. Toman medidas, anotan datos sobre la localización del nido y estiman la fecha de eclosión. “Yo cargo conmigo un rastrillo y con él borramos el rastro con el propósito de que si viene algún depredador no sepa donde está el nido, el depredador principal es el ser humano. Hacemos esto porque están en peligro de extinción y si no las protegemos, mis nietos y los hijos de mis nietos no las van a conocer”, afirma Luis F. Jiménez Concepción, uno de los vigilantes de las tortugas en la playa. Para Tania Ahorrio Matías, “esto es una lucha, es pacífica pero es lucha, es proteger algo que es de nosotros. Una tortuga que nace aquí en una playa de Arecibo es arecibeña y puertorriqueña”. Esta colaboradora de la organización ofrece charlas educativas, y participa del monitoreo, la excavación de nidos, el conteo de tortugas, la liberación de tortugas al mar, y en la limpieza de las playas. La iniciativa ciudadana cuenta con los permisos y la colaboración del Departamento de Recursos Naturales y Ambientales. No obstante, los voluntarios aseguran que la participación activa de la comunidad es indispensable para el éxito de este tipo de proyecto. Si interesa unirse, puede encontrar más información en www.yoamoeltinglar.com o escribir a info@yoamoeltinglar.com. Recurso: http://www.elnuevodia.com/cuidadoresdeunaespecieindefensa-1406763.html#.UMvLGd8U3xw.facebook ![]() By: Bernd F. Laeschke Southampton (global-adventures.us): Increased levels of nutrients in the water column can increase the susceptibility of corals to fall victim to bleaching, research conducted at University of Southampton’s Coral Reef Laboratory shows. Corals are marine animals that have a mutually beneficial, or ‘symbiotic’, relationship with algae that live in their tissue. Studies have shown that when water temperatures rise beyond a certain threshold, the corals expel the algae, which can increase mortality of the host and turns the corals white. “The increasing influx of nutrients in coastal waters due to human activities represents a pressing problem for coral reefs,” says Dr. Joerg Wiedenmann, head of the Coral Reef Laboratory. “A better understanding of the links between disturbed nutrient levels and coral bleaching is vital to develop marine and coastal management strategies, whichhelp to ensure future health of coral reefs.” Wiedenmann’s project ‘Incorals’ has been recognized by the European Research Council’s Starting Grant competition by granting a 1.29 million Euros award. The project will build on the initial findings and investigate the detailed mechanisms that underlie the responses of corals and their symbiotic algae to nutrient stress. The ‘Starting Grant’ scheme is a program aimed at early-career researchers, supporting a new generation of top scientists in Europe. Funding is provided to set up research teams and to develop the best ideas at the frontiers of knowledge. The 2012 competition attracted 4,741 applications competing for a share of the 800 million euro budget. A YouTube video explaining the research undertaken at the universities coral reef lab facility is available here. Current science suggests that coral bleaching is promoted by global warming, eventually threatening to wipe out coral reefs around the world. Coral colonies are symbiotic marine animals susceptible to rising water temperatures and increased nutrient levels. Approximately 10 percent of the world’s coral reefs are dead, and 60 percent are at risks due to human activity. Some dead corals are washed up on beaches around the world. Source: http://www.global-adventures.us/2012/12/11/coral-reefs-nutrient-levels-bleaching/ ![]() Everyone wants good news about coral, but we shouldn’t misinterpret the latest findings. By: Merinda Nash As Doha disappoints on delivering any real progress on reducing global CO2emissions, new research demonstrates that a key component of coral reef structures may be more resilient in the face of increasing CO2 levels, and consequent declining seawater pH, than was previously thought. However, while this is a good news story for the reefs, it does not mean that the entire reef is going to survive the negative impacts of ocean acidification associated with rising atmospheric CO2. While investigating the mineral structure of a common coral reef alga, Porolithon onkodes, we found that there was an extra mineral, dolomite, present in many of the algae collected from the high-energy reef front environment. These algae are known as coralline algae because, similarly to corals, they produce a carbonate skeleton. Corals produce a carbonate mineral CaCO3 called aragonite. The coralline algae form magnesium calcite, a mineral that is mostly CaCO3 but with 10-20% substitution by magnesium for calcium. In many reefs the upper-most reef front structure is predominantly built by coralline algae, as delicate branching corals cannot develop in this wave break zone. Therefore, discovering that this algae looks to be a survivor under higher CO2 scenarios is most definitely good news, particularly for tropical island communities that are protected from high energy waves by these algal ridges. The discovery that these algae produce dolomite, which is 50% magnesium instead of calcium and chemically very stable, was in itself an exciting discovery. Dolomite is most familiar to people as the mineral that gives the Dolomite Alps of Italy their name: dolomitized fossil coral reefs dominate the alps. This dolomitization process was thought to be a chemical alteration of the reef limestone that took place long after a coral reef had died. Discovering that living algae in modern coral reefs can form this dolomite prolifically meant reconsidering what we thought we knew about the chemical stability of these algae. Our experiments showed that dolomite corallines had 6-10 times less dissolution of the skeleton compared to the coralline algae without dolomite. Although dissolution increased in the high CO2 water, the total rate was still minimal. We found that dolomite was common in algae from many tropical reefs, but it seems to be restricted to the shallow, highest energy parts of the reef. What does this finding mean for the Great Barrier Reef and other tropical reefs? First, I must make clear that our research related to coralline algae, not corals. The Canberra Times and The Age ran the story with the headings “Coral may be climate change’s silver lining” and “Resistant algae good news for coral”. Considering our research was actually on algae, not coral, the Age has the most accurate headline. We are sadly accustomed to the critical role of coralline algae being overlooked in favour of the more visually appealing corals. Coralline algae are not the same as the symbiotic zooxanthellae algae that live within the coral branch. Coralline algae are a pink encrusting algae that grow over dead and living corals and other reef substrate. The reef front below the exposed coralline algae surface is typically built of overlapping layers of coral and coralline algae. Our results demonstrate that the structural role provided by this coralline algae looks set to continue under higher CO2 levels than we previously thought. The Australian reported our research with two other positive coral news stories with the headline “Forget the doom: coral reefs will bloom”. The coral stories related to corals thriving in conditions thought to be inhospitable to their survival. On the face of it this all points to a positive future for the coral reefs. However, the key point that is often missed is that a coral and a coral reef are not the same thing. Just because a coral grows, it does not necessarily follow that a reef will form, just as a few trees growing in harsh conditions does not indicate a forest can form. The recent CSIRO marine report card for ocean acidification identified the need for research at an ecosystem scale to understand the complex and sometimes inter-related responses of various reef organisms to ocean acidification. It is possible to have a reef made of coralline algae without corals, as happened ~16 million years ago during the Mid-Miocene climactic optimum when CO2 and temperatures were higher than today. However, a reef made only of coralline algae will not support the biodiversity presently found on our tropical reefs. With the Doha talks failing, maybe world leaders are counting on our world being more resilient to climate changes than we thought. While this research shows that coralline algae may be more resilient than we thought, unfortunately, we still can’t rely on this to save our reefs. Source: http://theconversation.edu.au/research-good-news-for-coralline-algae-but-not-necessarily-for-reefs-11255 ![]() Menhaden are modest little fish so rich in oil that they’re sometimes called the soybean of the sea. But scooping them up to fuel the omega-3 fish oil craze could pull the rug out from under the entire Atlantic coastal food chain. By Richard Conniff The small town of Reedville, Virginia, on the western shore of Chesapeake Bay, is a 1950s, Norman Rockwell sort of place. Bunting hangs from a white picket fence ahead of a holiday weekend, and there’s a tire swing in a front yard. The big, handsome houses on Main Street have wraparound porches and a smattering of gingerbread on the gable peaks. Reedville is also still a working town. Summer days start around 5 a.m. with the thrum and rumble of heavy diesels as the big fishing boats head out, followed at 5:50 by the whine of the spotter planes taking off. If a fishy smell, or even the occasional stink, wafts across Cockrell Creek from the Omega Protein Corporation’s fish-processing plant—Reedville’s major employer—locals just breathe deeper. They recently raised $350,000 to restore a beloved landmark, the 130-foot-tall smokestack of another fishmeal factory, now defunct. For almost 140 years, Reedville’s prosperity has depended on one species: the Atlantic menhaden,Brevoortia tyrannus. It’s a modest-looking little fish, generally under a foot in length, with a deeply forked tail and such rich reserves of oil that it’s sometimes called “the soybean of the sea.” A school of them leaves a slick in its wake. Dutch Harbor, Alaska, is the nation’s largest fishing port by tonnage and gets celebrated in “The Deadliest Catch” television series. But Reedville, home of the oiliest catch, comes in second—and gets widely vilified for it. Menhaden used to be unbelievably abundant on the Atlantic seaboard. When Captain John Smith visited the Chesapeake 400 years ago, he found them “lying so thicke with their heads above the water” that his crew tried to skip a step and “catch them with a frying pan.” New York Harbor, according to a 1679 Dutch travel account, also swarmed with “whales, tunnies and porpoises” as well as with osprey, all feeding on “marsbankers.” (Mossbunker, or bunker, is still a common name for the species.) Harvesting this resource became the business of the menhaden “reduction” industry in the mid-nineteenth century, after a fisherman’s wife in Blue Hill, Maine, figured out how to separate the oil from the menhaden’s flesh. As recently as the 1980s, dozens of reduction plants from Florida to Maine were still at it. But now the menhaden are going bust, according to a highly vocal coalition of scientists, conservationists, and recreational fishermen. Whereas they were once abundant along the entire Atlantic seaboard, the fishery has shrunk to an area from Virginia to New Jersey, and the annual catch has plummeted by almost 80 percent since the 1950s. Omega Protein executives like to point out that the commercial fishery leaves enough menhaden in the water to produce 18.4 trillion menhaden eggs annually. It sounds like a big number, and in theory it’s almost double what’s needed to maintain the species at target levels. But that 18.4 trillion is down from a peak of 117 trillion in 1961. Moreover, something in the process of turning those eggs into grown-up fish has gone badly awry in recent decades. Conservationists say overfishing is the problem, and they liken the collapse of the menhaden to the decimation of the great bison herds and the extinction of the passenger pigeon in the nineteenth century. Three-quarters of the remaining catch now goes to Reedville, which has the East Coast’s last surviving reduction plant. Hence Reedville’s split reputation. Depending on your point of view, it is a manufacturing center for what has lately become one of the healthiest and most highly prized products on the planet—omega-3 fatty acids in the form of fish meal and fish oil. Or it is the Death Star for marine species on the entire Atlantic seaboard. The modern battle over menhaden began one day in 1997, when a recreational fisherman named Jim Price turned up at the Maryland Department of Natural Resources with a malnourished and diseased striped bass he had caught. A pathologist there speculated that stripers may have gotten “decoupled from their prey,” and Price, who has no scientific training, thought, “What the hell?” But the phrase stuck in his head. At six o’clock one recent Saturday evening, at a dock on Maryland’s Eastern Shore where sports fishermen bring their catches to be cleaned, Price was scissoring open the bellies of striped bass carcasses. With each dissection, he called out a litany of data, to be noted down by his wife Henrietta: “Thirty inches. Male. Zero body fat. Spleen good. Stomach empty.” Price is a jeweler and gem dealer by trade, 69 years old, overweight, hunched, with big rimless eyeglasses on a knobby round face. His manner is both plodding and mildly hectoring. Henrietta has learned to fend him off in an endless round of spousal thrust-and-parry. But no one can keep him from talking about either striped bass or menhaden, preferably both, in a relentless monologue punctuated with phrases such as “I’m the only one out there who sees this” or “They don’t understand like I do.” At one point, midway through a dissection, he mentioned that he has cancer of the colon and liver and that his doctor gave him a few months to live, three years ago. Then he cut open the next fish. A few of the striped bass carcasses that evening had men-haden in their bellies, swallowed whole. One came out ghoulishly half-digested, eyes gone, skin dissolved, muscle just receding from the pearly, translucent tips of its ribs. But most of the 55 fish Price dissected had empty stomachs and zero body fat. And it was his passionate contention, from 10,000 such dissections, summer and winter, that striped bass in the Chesapeake Bay are starving. They are starving, he said, because the reduction industry has fished the menhaden almost down to nothing. Many of the most familiar Atlantic Coast predators, from bluefish to humpback whales and from pelicans to bald eagles, depend on menhaden. Like herring, sardines, anchovies, and other small, prolific species, menhaden are “forage fish” and vital as prey for other species. Or as a sports fisherman explained to me, “In nature it’s eat or be et, and menhaden are on the ‘be et’ side of the equation.” What’s happening to them also fits what scientists say is a dangerous pattern of overharvesting forage fish and jeopardizing their predators worldwide. Off the coast of Peru this year, for instance, overfishing of anchovies, together with shifting weather patterns, has caused massive die-offs of seabirds and dolphins. In April, the Lenfest Forage Fish Task Force, a panel of marine and fisheries scientists, called for cutting the catch of forage fish globally by half. It also calculated that forage fish would be worth twice as much to fishermen if they just left them in the water to be eaten by pricier species such as striped bass, cod, or tuna. The idea that overharvesting little fish starves out the bigger ones is an old complaint. Fishermen in the 1870s actually rioted and burned down a menhaden reduction plant on the coast of Maine because they blamed it for the loss of cod and other valuable species. The same concern for species farther up the food chain has in recent years caused every East Coast state except Virginia to ban the reduction industry within its waters. The complaining has gotten louder in recent years, partly because of the importance of Chesapeake Bay as a nursing ground for the entire East Coast and partly because some people have begun to question the logic of investing large sums to restore other commercial fish species if there aren’t enough menhaden out there for them to eat. The target for these complaints has also become more obvious: concentration of the industry means that the fate of the Atlantic menhaden may now be determined by a single state and a single corporation, Omega Protein. People in Reedville, where Omega Protein has 275 employees and a dwindling fleet of just nine boats, tend to return the complaints, times two. “The campaign by conservationists is not about cutting back. It’s not about getting more fish. It’s about getting rid of Omega Protein,” said Jimmy Kellum, who owns two menhaden boats and sells about half his catch to the reduction plant. He fumed a bit as he slapped paint on parts for a new boat he was building. Then he added, “What right does Florida or Maine have to say what we can do with our resource? I know you’re going to say he’s a migratory fish. But he’s mine when he’s in my yard.” If menhaden have been largely absent from New England waters since the early 1990s, it’s not Reedville’s fault, he said. “That’s God’s will, whether he contracts the fishery, or expands the fishery into Maine.” At dawn one recent morning, just off Tangier Island in mid-Chesapeake, the start of the day’s fishing felt like a military maneuver, with a fleet of big boats—up to 170 feet in length—milling about and spotter planes circling in a Cessna dogfight overhead. “Can’t get my eye on any color right now,” a pilot drawled over the radio on the Indian Creek, one of Kellum’s boats, a former Navy tug now converted to purse-seine fishing. Menhaden travel in such densely packed schools that they appear as inky splotches on the surface. Spotter pilots become adept at reading the color and the “whips”—or surface splashing—to estimate the number of fish to the nearest 10,000. Menhaden breed offshore, and the juveniles then make their way into estuaries, with the Chesapeake serving as the most important nursing ground on the Atlantic seaboard by far. Some menhaden overwinter there. Others begin to arrive in May as vast schools of menhaden migrate northward. “I see two or three here this morning,” said the pilot, meaning schools of fish. “They ain’t no whackers, but they’re worth a set.” A big, open tub of a boat with six crewmen aboard motored away from the Indian Creek. Under direction from the airplane, it dropped a 1,200-pound sea anchor with one end of its purse seine attached and began paying out the rest—900 feet of buoyed rope from which the net drifted down like a curtain. “Steady, steady, steady,” said the pilot, as the boat slowly circled. “Come right around on ‘em. Lookin’ good. Got every bit of it. Now, just like that, go into the sea anchor. Color there is good.” With the net now surrounding the school of menhaden, the crew began drawing in a rope that runs through metal rings along the bottom edge, cinching it closed like a coin purse. The clanking of metal parts mixed with sounds of water sheeting down, men shouting, and the spattering of the fish across the surface as the circle steadily contracted around them. Men in their oilskins reached over to haul in the net, their faces straining, hair flecked with fish scales. The Indian Creek, which had now pulled alongside, lowered a big vacuum tube down into the seething pocket of fish, and the menhaden came flying up into the fish hold, where the streams of chiller water turned murky red with blood and oil. The Indian Creek would sell that day’s catch to the bait trade, mainly for crabbers in the Chesapeake and lobstermen as far north as Maine. But most of the other boats that day were bound for Omega Protein, where 550 million menhaden a year get reduced to fish meal and oil—and ultimately transformed into human food. The name “menhaden” comes from a Native American word for fertilizer, and it’s generally thought to be the species Squanto advised the Pilgrims to plant with their corn. On the Connecticut coastline, where I live, farmers used to apply them to their crops at a rate of 10,000 per acre—enough to make even a Reedville resident gag. Menhaden meal has been an ingredient in chicken, pig, and dairy feed since at least the nineteenth century. It’s now also a standard part of the diet on many fish farms, where it typically takes four pounds of forage fish to produce a pound of the salmon and other species we like to eat. Menhaden rarely turn up on our dinner plates baked, fried, or otherwise; the combination of oil and bones is just too daunting. But we eat menhaden more often than we generally realize. It is a key ingredient, for instance, in the Smart Balance Omega-3 spread I buttered onto my toast this morning, and it’s one reason the eggs I just ate, formerly deemed a cholesterol nightmare, are now prominently labeled as a heart-healthy omega-3 product. Highly refined menhaden oil also turns up in salad dressings (such as Cindy’s Kitchen All Natural brand), cookies (Trader Joe’s Five Seed Almond Bars), and other products that can seem just a little healthier thanks to the omega-3 halo effect. Almost everyone I spoke with, on both sides of the menhaden fight, also seemed to be taking fish oil in capsule form, at times with almost religious devotion. Research since the 1990s has demonstrated persuasively that omega-3 fatty acids promote normal brain and eye development and can protect against heart disease—hence their reputation as a “miracle food.” Menhaden is a latecomer to this booming market. Most fish-oil capsules instead contain oil from sardines and anchovies caught on the Pacific Coast of South America. Neither these species nor menhaden actually produce the omega-3 oil themselves. They get it from the algae they eat. And yes, that means it’s possible to bypass the fisheries issue entirely and get your ritual omega-3 dose from algae, too. At a laboratory in a nondescript office park in Columbia, Maryland, a few hours north of Omega Protein, for instance, researchers for Dutch conglomerate DSM take microalgae gathered from beaches or scraped from boat hulls and use them to brew omega-3 oils the way other companies brew beer or antibiotics. But the resulting oil retails for two or three times the price of fish oil. Hence Omega Protein sees a market niche and better profit margins by moving menhaden into the “nutraceuticals” market. Through recent acquisitions, it has its own retail fish-oil brand, Omega Activ. For now, though, the company is still mainly in the business of selling menhaden as animal feed; according to an Omega Protein spokesman, more than half the company’s menhaden catch now goes to China and other Asian markets as pig and fish feed. People who study fisheries often worry about “shifting baselines,” the insidious tendency to lose track of history and make decisions based only on living memory. It’s what drives fishermen to oppose regulation on the grounds that they had a good catch just last week, or last year—never mind how things looked 40 or 400 years ago. And yet, if you need a sense for how bad things have gotten with menhaden, sometimes memory serves just fine. In Maine, where they are known as pogies, menhaden were abundant enough in the early 1990s to be deemed a nuisance. Under hot pursuit by bluefish and other predators, whole schools of them would pile into narrow estuaries, where they soon consumed all the available oxygen and died. Horrified vacationers awoke to find fish floating in vast, stinking, yellow mats. Lobsters actually climbed out of the water in desperation. A headline announced, “Massive Kill Means Dead Pogy Season Has Arrived.” The good news was that Maine fishermen caught 60,000 tons of menhaden in a season then. Their biggest customer was a rusting, Soviet-era factory ship named the Riga, which had anchored offshore and was doing a brisk business grinding up menhaden to feed chickens and pigs back in Murmansk. I got a first-hand sense of how abundant the menhaden were one summer 20 years ago, when I headed out of Rockland, Maine, at midnight aboard a fishing boat named the Bobby E, bound toward an amber light a few miles offshore. To get aboard the Riga, I had to step off the Bobbie E in the dark, clamber across great, elephantine Yokohama fenders floating at the waterline, and climb a skewed wood-and-rope ladder banging against the hull. The Riga’s factory equipment was primitive. A noisy conveyor belt delivered the fish to a device like a paper shredder which reduced them to a kind of brown sludge, and then . . . but you don’t really want to know. Every surface of the processing area was caked with fishmeal, as if breaded and fried. Fishmeal also drifted up in the corners, like dust in the bottom of a cereal box. An American intermediary living on board told me he had killed a dozen rats in his cabin just within the past month. What really stuck in my memory, though, was the abundance of menhaden. Riga crewmen, including the ship dentist, vied to work as “lumpers” down in the hold of the Bobby E. Their job, by the light of a bare 60-watt bulb, was to climb up the great walls of stacked menhaden and kick them down in an avalanche toward a large vacuum tube, to be sucked up onto the ship. They came out smeared head to toe in menhaden gore, but with 50 cents a ton in their pockets. When I woke up next morning back in Rockland, that whole night seemed like a strange dream, and it still seems like a dream today because the menhaden soon vanished from the coast of Maine. The annual menhaden catch there is now close to zero, and it’s stayed that way for almost 20 years. In fact, in all of New England only a single bait company still fishes for menhaden. It’s based in Rhode Island but often has to travel to New Jersey to find fish. A few people in Virginia still remember the Riga, too, and it serves them as a fallback line of defense. If there really is something wrong with the menhaden fishery, they told me, it isn’t the fault of Omega Protein’s menhaden fleet in Reedville. They blamed it on the Russians instead. In fact, the health of the menhaden population has always been the business of the Atlantic States Marine Fisheries Commission (ASMFC), a 15-state organization that jointly regulates coastal fisheries. But seeing the commission in action does not inspire much confidence, even within its own ranks. It was a small moment, but seemed like a portent, when I got on a hotel elevator en route to a recent ASMFC meeting. The elevator voice said, “Going down,” and the only other passenger bleakly commented, “In so many ways.” He turned out to be the commissioner from the National Marine Fisheries Service. At the meeting itself, 45 people, mostly older white males, sat at tables arranged in a huge rectangle and collectively dithered. They had previously decided to manage menhaden not just by traditional, single-species standards, but also based on how menhaden affect other species that depend on them as prey. A commissioner remarked that he couldn’t figure out how to do this kind of ecosystem management “in a pond in my backyard, much less in the Atlantic Ocean.” When a technical committee staffer said it would require $350,000 to develop rigorous scientific standards, a commissioner truculently suggested that activists in the audience come up with the cash. Then they voted to wait and see if the $350,000 might somehow turn up by their next meeting. Jim Price, who was there with his striped bass numbers, called it “management by procrastination.” Until recently, scientists at both the ASMFC and the National Marine Fisheries Service repeatedly assured everyone that the menhaden population, though highly cyclic, was doing just fine. But Price kept saying otherwise, and other recreational fishermen—and, more gradually, fisheries biologists—lined up behind him. The failure of the menhaden, year after year, to come back in anything like the numbers seen even in the 1980s (much less the 1800s) also made the scientific assurances seem increasingly wishful. The way fisheries biologists determine the health of the menhaden population is too complicated even for most commissioners to understand. As with other species, it involves a computer model with lots of assumptions built in. The model for menhaden has turned out over the past few years to be badly flawed. Until recently, for instance, it did not bother to calculate how many menhaden were being killed by bluefish, stripers, and other predators—meaning that a bigger take for commercial fishermen seemed sustainable. Then, in 2010, a Maryland state fisheries biologist working line by line through computer code noticed an error that effectively double-counted some menhaden data. Finally, a peer review by independent scientists knocked out the most fundamental assumption in the menhaden model. When commercial fishermen talk about leaving enough menhaden in the water to produce 18.4 trillion menhaden eggs annually, they’re referring to an ASMFC standard. It’s based on the assumption that maintaining just eight percent of the menhaden population’s “maximum spawning potential” is good enough. That’s an unusually low number—“We don’t even manage some invertebrates at that level,” a Maryland fisheries biologist told me. The peer-review panel said that the ASMFC had failed to protect the stock—and that verdict forced, at the very least, a show of change. At a meeting last year the commission voted to boost the eight-percent threshold to a minimum of 15 percent, with a target of 30 percent. It acknowledged for the first time that there had been “overfishing.” In fact, by its new standards, overfishing of menhaden has occurred in 32 of the past 54 years. It also made the somewhat Orwellian distinction that menhaden were not yet “overfished.” That is, they might be flirting with disaster. But they hadn’t arrived. So far, none of these changes has had any effect on the menhaden fishery, and it’s possible they never will. Analysis by scientists suggests that rebuilding the menhaden fishery could mean cutting the catch by as much as 37 percent. But the commission has yet to decide whether to reduce the catch at all, or on what timeline. Commercial fishermen profess optimism that this process will work out in their favor. The ASMFC’s critics, on the other hand, tend toward cynicism. “There’s a lot of politics surrounding this, probably more than in any fishery I’ve ever been involved with,” said Jud Crawford, a biologist with the Pew Environment Group. He worries that Omega Protein will thwart the process “or find a way to influence the stock assessment, which should not be possible in an ideal world.” The cynicism derives in part from the commission’s one previous attempt to protect the menhaden. In 2005, responding to public protest, it set a limit on the menhaden catch in the Chesapeake Bay. But the limit was so high as to be “imaginary,” according to one ASMFC commissioner. “They would have had to significantly increase their fishing to reach the cap.” Even so, both the company and Virginia state officials vehemently resisted. Omega Protein’s lawyers drafted a legal brief, and Virginia’s then-attorney general, Bob McDonnell, used it to argue that Virginia could ignore the ASMFC cap. The eventual compromise was “a farce,” said Jim Price. “It’s now eight years without a single fish being saved.” Virginia is already resisting any new limits on the menhaden catch. McDonnell, now governor, personally lobbied other governors before the ASMFC vote last fall to oppose raising the eight-percent standard. The state delegation has also maneuvered to delay any effort to rebuild the menhaden population, pushing for a ten-year schedule, twice the usual timeline for a recovery effort. What will happen if the menhaden fishery ultimately faces a real reduction, on a tighter timeline? (A decision on the issue may come at the ASMFC meeting December 14.) A state senator in Virginia has already introduced legislation to secede from the ASMFC. But a more likely outcome would be another compromise, after years of legal wrangling. Probably no one is more cynical about this process than Rutgers professor H. Bruce Franklin. After he published The Most Important Fish in the Sea in 2007, he said, Omega Protein sent a legal brief to the university, alleging factual errors and “implying that they were going to take Rutgers to court if it didn’t shut me up.” The tactic failed, but it touched a sensitive nerve for Franklin, who was once forced out of a tenured post at Stanford University for his leftist political activities. Asked what he thought was likely to happen with the menhaden fishery now, he hesitated for a moment, then remarked, “The line from Chinatown popped into my head: ‘As little as possible.’” But there is one final outcome that might be even more disturbing than the messy political fighting and procrastination over menhaden: it could turn out that Omega Protein is not the ultimate cause of the problem. That would no doubt annoy some conservationists for whom the company has served as a convenient target. But much worse, it might mean the menhaden fishery is broken beyond easy repair. Scientists say they simply can’t promise that making Omega catch fewer fish will lead to recovery of the population. In theory, it ought to work: a mature menhaden female can produce 500,000 eggs annually, enabling even a heavily fished population to bounce back when the environmental circumstances are right. But the failure of the population to rebound for 23 years straight suggests that something else is going on now, said University of Maryland biologist Edward D. Houde, a member of the Lenfest Forage Fish Task Force. One hypothesis is that it’s a periodic shift in weather patterns offshore, where the menhaden spawn. In the past, a “Bermuda high” in March seemed to sweep more young fish into the Chesapeake, promising a good year for menhaden. Or an “Ohio Valley low” kept them out at sea. But that pattern seems to have broken down over the past two decades. The larger problem of climate change may also mean that more menhaden are bypassing the Chesapeake, said Houde, and moving into estuaries farther north, where “the habitat isn’t big enough to produce what used to be produced.” Finally, there is the dismally polluted state of the Chesapeake itself—to which, ironically, the menhaden may now contribute, by being served up as feed on Maryland’s many poultry farms and then returned to the water in the form of nitrogen runoff. These are big, intractable problems. Even so, said Houde, reducing the catch now is about the only short-term fix available, and it’s the right thing to do. Such reductions in the past have brought about recovery for species such as striped bass, mackerel, blue crabs, and summer flounder—as well as for the commercial fishermen who depend on them. This time, moreover, it’s not just about a single species. In Reedville, people naturally focus on the painful economic consequences if the menhaden fishery faces a reduction. But it raises the larger question: What will happen if the base of the entire Atlantic coastal food chain disappears? Richard Conniff’s articles have appeared in Time, Smithsonian, The Atlantic, National Geographic, and other publications. He is a 2012 Alicia Patterson Fellow and author of The Natural History of the Rich, Spineless Wonders, and Swimming with Piranhas at Feeding Time. His latest book is The Species Seekers, published in 2011 by W. W. Norton & Company, Inc. Source: http://conservationmagazine.org/2012/12/the-oiliest-catch/ ![]() A high level of coral cover doesn’t always mean a high level of species diversity By: Zoe Richards The health and productivity of coral reefs is rapidly declining. Hard corals are the principal builders of coral reef ecosystems; however they are struggling to survive due to pollution, catchment clearing and climate change. The task of curtailing these declines is immense. To protect coral reef ecosystems, a portfolio of management approaches are needed. This includes Commonwealth and State leadership and community participation. Most importantly, management actions must be based upon pragmatic science. Currently the health of coral reefs is reported in terms of the level of coral cover. It is assumed that a reef with high cover is healthier than one with low cover. This information ultimately influences the selection of marine reserves. However, new research shows that reefscape metrics such as coral cover are not linearly related to richness of a coral species. This means that if a reef is designated as healthy and consequently given an elevated level of protection (for example, made a no-take zone) because it has a high level of coral cover, the biodiversity benefit of protecting this reef may not be as high as first expected. Moreover, results of this study show that the relationship between coral cover and coral diversity is far from simple. Coral biodiversity actually peaks at intermediate levels of coral cover. This finding is not unusual, considering coral communities can be dominated by a single or small number of species that can reach an incredibly high level of cover. This can occur when a community is in an early phase of recovery after a disturbance or when there have been no disturbances for a long time. Alternatively, it is quite common for coral communities to have a large number of species that occur as small, sparse colonies. Therefore even if coral cover is not high, there is a high level of diversity. If coral biodiversity is high, this benefits all of the fish, crustaceans and other associated marine life. Knowing about the lack of a positive linear relationship between coral cover and coral biodiversity is important information for coral reef managers. This is because biodiversity lies at the core of ecosystem health, productivity and functioning. Especially on disturbed reefs, a large pool of species is required to sustain ecosystem structure and function. Evidence is mounting that individual species are important to ecosystem resilience and that even small changes in diversity can have significant impacts on ecosystem function. One of the most ominous consequences of reef degradation is the loss of biodiversity. Despite this, in most reef regions there is little information about species occurrences, or about species' responses to management and environmental change. Moreover, financial and logistical constraints mean that proxy measures are not necessarily used in coral reef monitoring. The best proxies are those that are reliable, easily quantified and documented as a simple linear function. Results presented in this study indicate that while coral cover performs poorly as a measure of species richness; genus diversity performs well because it is strongly and linearly associated with species richness. This suggests that collecting data on coral genus diversity would be a valuable addition to coral reef monitoring programs. Ultimately the loss of biodiversity is irreversible and the ecosystem effects are unpredictable. The ability to detect and monitor biodiversity is vital if we are to protect it. Source: http://theconversation.edu.au/a-lot-of-coral-doesnt-always-mean-high-biodiversity-10548 |
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