CORAL REEF CONSERVATION AND PROTECTION: INTERNATIONAL INTERVENTION.

It is now generally acknowledged that coral reefs are among the most threatened global ecosystems and among the most vital (West & Salm, 2003). Reefs are of critical importance to human survival ( especially in developing countries) because they provide subsistence food for a substantial portion of the population, serve as the principle coastal protection structures for most tropical islands, and contribute major income and foreign exchange earnings from tourism.  The impressive worldwide economic value alongside untold medical benefits inherent worth of the worlds coral reefs create strong arguments for conserving these threatened living structures.

Historically management practices have focused on the coral reef as a single unit and not considered associated communities, such as seagrasses, mangroves, mudflats or defined watersheds (which transport complex mixtures in their waters). This method managed the reef in isolation, like an island.

However recently there have been increasing efforts to establish better management and conservation measure to protect the diversity of these biologically rich areas. Current management efforts recognise the importance of including reefs as part of a larger system. Where integrated coastal zone management tools and watershed concepts can be used in the development of comprehensive management and conservation plans.

There are three existing and emerging approaches to international reef conservation, all use a basic method of marine protected areas but vary in the area in which they cover, worldwide, regional and individual.  

1. Special protection status for coral reefs e.g. Convention on Biological Diversity.
2. Regional reef protection agreements and regional coordination e.g. Coral Triangle Regional Agreement.
3. Protection of individual reef species.

Conservation: Convention On Biological Diversity.  

Approximately 6% of the worlds land is in parks but at sea less than one half of a one percent is in any kind of protected area.  The convention on biological diversity (CBD) has worked to implement Marine Protected Areas (MPA’s) as a means by which to protect coral reefs.  MAP’s are broadly split into three distinct groups. Areas managed for sustainable use, which may allow extractive uses, areas where extractive uses are excluded and other significant human pressures are minimised (known as no-take zones) and finally sustainable management over the wider marine and coastal environment.

The CBD Parties acknowledge that individual MPAs are not enough to adequately protect biodiversity within those MPAs, and this is why they see an MPA network approach as “essential.” The CBD Parties have also taken up the issue of how coral bleaching relates to the establishment of MPAs, creating a “Work Plan on Coral Bleaching” that includes some “high priority actions.” These actions include identifying “coral reef areas that exhibit resistance and/or resilience to raised sea temperatures” and “integrating bleaching resilience principles into MPA network design” and “reducing other localized stresses (water quality, overfishing, etc.).”

Conservation: Coral Triangle Regional Agreement.

The “Coral Triangle” is a 2.3 million square mile area in the Indo-Pacific Ocean that boasts the highest biodiversity of any reef system on the planet. Between 500 to 600 reef-building coral species live here, compared to 350 such species in Australia’s Great Barrier Reef, and just 70 such species in Belize’s Barrier Reef. Unfortunately, the reefs of the Coral Triangle face all the threats discussedin previous blogs, including coral bleachings that hit these reefs hard, particularly in 1997 and 1998. Also, destructive fishing practices, such as the use of dynamite, are “quite prevalent” in the area, damaging corals all the more. And perhaps worst of all for the area’s reefs is the concentrated human population—approximately 150 million people live in the Triangle area, producing large amounts of pollution that further limit the ability of corals to persist.

Yet it is not all bad news for the reefs of the Coral Triangle. In December 2007, top officials from the six Coral Triangle nations (Indonesia, Malaysia, Papua New Guinea, the Philippines, the Solomon Islands, and Timor-Leste) agreed to create an action plan to manage the Triangle sustainably. These countries finalized this plan in October 2008, and formally adopted it in May 2009, at the World Ocean Conference in Indonesia. Numerous entities, including the World Bank and the Asian Development Bank, have offered to help these six nations pay for their planning efforts. The United States also pledged nearly $40 million to the project.

Conservation: Protection of Individual Reef Species.

Unlike the previous two approaches to coral reef protection this third and final approach focuses on individual species within coral reef ecosystems.  Essentially this approach uses the convention on international trade of endangered species to prevent the trade of wild and endangered coral species. However it is difficult to firstly get corals listed on the CITES appendices and once it is it is difficult to enforce with counterfeit documentations .

Join me over the next twenty for hours where I'll discuss the non international approaches for coral conservation, examples of marine protected areas, no take zones and draw my final conclusion on whether coral reefs really are suffering a crisis. 

THE BLOG I FORGOT: NATURE OR NURTURE, THE CONCLUSION.

Prior to starting this blog I had made a plan of where I wanted to go with it, with ideas for each blog.  Despite this remarkable organisation on my part it would appear I have forgotten to draw my own conclusions for the series of blogs titled CURRENT DAY THREATS TO CORAL REEFS: NATURE OR NUTURE? So, as the saying goes, better late than never!!!

This series looked at the threats faced by coral reefs and broadly split them into two categories nature (natural environmental change) and anthropogenic inputs (nurture). 

Climate change is a very natural process that has occurred throughout the earth’s history. Both extremes (warm and cold) have been experience; they have been both abrupt and long lived in terms of formation and duration. However despite this corals have survived previous episodes of climate change. 

In my opinion the risk of extinction and threat to modern day corals is not a result of natural climate change.  Yes, climate change plays a role but it is the added anthropogenic factor which is ultimately the biggest threat to corals.  In previous warm periods Corals and their mutualistic zooxanthellae have acclimatised, however research suggests that at the present rate of climate change they are not acclimatising quick enough. So what is different this time round ......

.....the anthropogenic factors.  Industrialisation and subsequent population growth have exacerbated the natural climate change with an increase in carbon dioxide and thus sea surface temperatures and increasing ocean acidification and bleaching events. Coral are also threatened directly by human activities e.g. over fishing, destructive fishing practices, tourism and introduction of invasive species. 

CORAL REEFS IN THE NEW: ANCIENT CORALS PROVIDE INSIGHT ON THE FUTURE OF CARIBBEAN REEFS.

Climate change is widely recognised to be a major threat of current day coral reefs. In a paper published last week in the Journal of Geology, University of Miami (UM) scientists use the geologic record from nine Caribbean sites to understand how reef ecosystems might respond to climate change expected for this century.  The Pilocene epoch (some 2.5 million years ago) provide some insight into what coral reefs may look like in the future. Estimates of carbon dioxide and global mean temperatures of this period are similar to environmental conditions expected in the next 100 years.

This science daily article provides a brief over view of the a paper and its finds .........

http://www.sciencedaily.com/releases/2011/04/110407141336.htm

Or if you prefer here is the link to the paper.......

http://geology.geoscienceworld.org/cgi/content/abstract/39/4/375

P.S. don't forget to join me over the weekend to discover what we can do to help save the coral reefs for future generations.

WHY ARE CORAL REEFS IMPORTANT?

All of these human induced threats serve to alter sediment levels (thus light), salinity and nutrients and such threatening the survival of coral reefs.   

Hidden beneath the oceans’  water, coral reefs teem with life. Fish, corals, lobsters, clams, seahorses, sponges, sharks and sea turtles are only a few of the hundreds of thousands of creatures that rely on reefs for their survival. Reefs  are home to an amazing variety of plants and animals from microscopic bacteria and protists to invertebrates and 1000’s of species if fish.  With 58% of the worlds coral reefs potentially threatened by anthropological and environmental threats (see WWF link before) we look at why they are important before we access how best to protect them.

Intrinsic value.

Coral reefs are also living museums and reflect thousands of years of history. Coral reefs are an integral part of many cultures and our natural heritage. In fact, coral reefs are some of the oldest and most diverse ecosystems on the planet.

Economic Value.

Beyond their intrinsic value and their role as a breeding ground for many of the oceans fish and other species, coral reefs provide human societies with resources and services worth billions of dollars each year. Millions of people and thousand of communities all over the world depend on coral reefs for food, protection and jobs. These numbers are especially staggering considering that coral reefs cover less than one percent of the earth’s surface.

Healthy coral reefs support commercial and subsistence fisheries, as well as jobs and businesses that support tourism and recreation.  Coral reefs are vital to the world’s  fishers. They form the nurseries for about a quarter of the oceans’  fish and thus provide revenue for local communities as well as national and international fishing fleets. An estimated one billion people have some dependence on coral reefs for food and income from fishing.  In the United States, coral reef ecosystems support hundreds of commercial and recreational fisheries worth millions of dollars to state and local economies. One estimate suggests the commercial value of U.S. fisheries from coral reefs is over $100 million (NOAA). In the U.S. territory American Samoa, coral reefs play an important cultural role and supply over 50 percent of the fish caught locally for food. Fish caught on reefs are a vital source of protein. Nearly ten percent of all fish consumed worldwide is caught on reefs, with one square kilometre of healthy reef providing enough fish to feed three hundred people (Mulhall 2007).

Local economies also receive billions of dollars from visitors to reefs through diving tours, recreational fishing trips, and other businesses based near reef ecosystems. Every year, scuba divers, snorkelers, and fishermen visit coral reefs to enjoy their abundant sea life. Reefs provide millions of tourist related jobs in more than 100 countries. In the 1990s, over four million tourists visited the Florida Keys each year, contributing $1.2 billion annually to tourism-related services (NOAA). In fact, the Florida Keys are the prime  dive destination in the world. In Hawaii, a state with many coral reefs, one popular reef alone is visited by over three million tourists each year. In the U.S. territories of Guam and the Northern Mariana Islands, over 90 percent of new economic development is dependent on coastal tourism, including reef tourism (NOAA).

Protective Barrier.

The coral reef structure also buffers shorelines against waves, storms, hurricanes and floods, helping to protect loss of life, property damage and erosion. More than 450 million people live within 60 kilometres of coral reeds, the well-being of their communities and economies is directly dependent on the health of nearby coral reefs (Mulhall 2007).  Healthy reefs absorb as much as 90% of the impact of wind generated waves and thus help to prevent coa stal erosion, flooding and loss of property on the shores (Mulhall 2007).  These reefs save billions of dollars each year in terms of reduced insurance and reconstruction costs and reduced need to build costly coastal defences – not to mention the reduced human cost of destruction and displacement.

Medical Benefits.

Finally, coral reefs are sometimes called the “medicine cabinets” of the 21st century (NOAA). Coral reef plants and animals are important sources of new medicines being developed to treat cancer, arthritis, human bacterial infections, heart disease, viruses, and other diseases.  Thus far researchers have identified  dozens  of antimicrobial, anti-inflammatory, and other medical properties in reef species.  For example, chemicals from a Caribbean reef sponge are used to produce AZT, a treatment for the human immunodeficiency virus (HIV) (Mulhall 2007). Some coral reef organisms produce powerful chemicals to fend off attackers, and scientists continue to research the medicinal potential of these substances. In the future, coral reef ecosystems could represent an increasingly important source of medical treatments, nutritional supplements, pesticides, cosmetics, and other commercial products.

Conclusion.

Despite their great economic and recreational value, a range of human activities now threatens these important habitats (previous blogs). Many of the world’s reefs have already been destroyed or severely damaged by water pollution, overfishing and destructive fishing practices, disease, global climate change, and ship groundings. Once coral reefs are damaged, they are less able to support the many creatures that inhabit them. When a coral reef supports fewer fish, plants, and animals, it also loses value as a tourist destination. Further, the absence of reefs acting as natural barriers can increase the damage to coastal communities from normal wave action and violent storms. Therefore, the health of coral reefs depends on sustainable human uses that promote economic development while protecting sensitive coral ecosystems and the creatures that reside there.

References.

http://wwf.panda.org/about_our_earth/blue_planet/coasts/coral_reefs/coral_facts/

http://celebrating200years.noaa.gov/foundations/coral/side.html

Mulhall, M. 2007. Saving the rainforest of the sea: an analysis of international efforts to conserve coral reefs. Duke environmental law and policy forum. 19: 321- 351. 

CURRENT DAY THREATS TO CORAL REEFS: NATURE OR NURTURE? (PART 4)

Part 3 looks at the existing and emerging threats to corals reefs as a result of non-climatic anthropogenic factors. Here I review Mulhall (2007) SAVING THE RAINFORESTS OF THE SEA: AN ANALYSIS OF INTERNATIONAL EFFORTs TO CONSERVE CORAL REEFS (PART III A).

The world’s coral reefs are on a downward trajectory. A study in 2004 estimated that since the 1950’s twenty percent of all reefs worldwide had been destroyed, with no chance of recovery, and an additional twenty-four percent of reefs were under imminent threat of collapse. These worldwide declines are a result of numerous causes; they can be global threats (part 1 & 2) whilst others are localised to specific countries and regions (like those discussed below).

Overfishing: Overfishing is a worldwide problem, having wiped out a third of the world’ s fish stocks.  Fishermen are   catching  smaller fish species which are lower down the food chain, not only to make a living but for a rich source of protein and to  ensure they and their families survive. Coral reefs are known for the biodiversity and abundant fish numbers, however over fishing here has many problems. It not only causes harm to  the humans who depend on them for food but also harms  the coral reefs where these fish once lived. Coral reefs have a complex relationship with the fish that live within them. Reefs provide security and habitat for many species of fish and in return herbivorous fish control the abundant algae found in reef environments. Without adequate number of plant-eating fish a reef can become overwhelmed by algae.    

Destructive Fishing: there are two types of fishing practices which not only deplete fish stocks but also damage the reefs themselves:

Blast fishing- involves the use of dynamite to stun and kill the fish which then float to the surface. This method almost certainly guarantees the fisherman a large catch BUT the dynamite kills all marine life in the area including sensitive corals and leaves nothing to replenish fish stocks with.

The use of cyanide :   cyanide is poured into the water around the reefs, stunning tropical fish and allowing for their capture, albeit for the ornamental aquarium fish market or for food. Despite being outlawed in many countries, one million kilograms of cyanide has been illegally used for fishing in the Philippines since the early 1960s. As with blast fishing, cyanide has a devastating impact on surrounding corals and other marine life.    

Pollution: because coral reefs only live in warm environments with abundant sunlight, they are found in shallow waters along the coastline. Unfortunately for coral reefs 40% of the world population also live along these coast lines.  Approximately 80% of all marine pollution now comes from land-based activities, including agricultural, municipal and industrial runoff, agricultural wastes, and atmospheric deposition. Coral reefs’ close proximity to land renders them especially vulnerable to this land based pollution. Agricultural and industrial runoff carries herbicides and other chemicals that harm corals, in addition to excess nutrients that create algae and phytoplankton blooms that suffocate corals. Other types of land-based pollution, such as sewage, wreak havoc on coral reefs as well. In Indonesia, a country located at the centre of the greatest known land and marine biodiversity on the planet, massive migration of the population from rural areas to coastal cities is taking its toll on the country’s reefs. Of all the pollution washing off the land and into the reef systems, untreated sewage is likely the worst. In Jakarta, the capital city, enough untreated sewage is released directly into the bay “to fill seventy-five Olympic-sized swimming pools, each day.” By 1993, one biologist had noted that all the coral reefs in Jakarta Bay were “functionally dead”.

Tourism: When done in the wrong way, tourism associated with coral reefs threatens the very reefs on which the industry depends. The global economics of reef based tourism are huge, (just under 10 billion dollars a year); Australia’s Great Barrier Reef supports a $4.2 billion tourism industries alone, with nearly two million tourists each year.

Irresponsible tourism threatens reefs in a variety of ways: from careless swimmers and divers, to improperly placed boat anchors, to discharges of sewage and other water waste from hotel and resorts. The cruise ship industry is of particular concern for reefs, given the sheer magnitude of the business. Cruise ships regularly “disgorge” throngs of passengers onto coastal reef areas, with around two thousand cruise ship passengers diving in Cozumel, Mexico’s reefs, in any  given day.

Mining: in East Africa Southeast Asia and the Pacific Ocean coral reefs are mined for their large quantities of limestone (calcium carbonate). This limestone can be mixed with sand and water to create cement and be used in the building industry. Alternatively it is used in the pharmaceutical industry to make pills and more recently researchers have mined corals for bone graft clinical trials. Often the corals are mined simply for piece  of dead and living coral which can be used in home as decorations and in jewellery worldwide. 

Invasive Species that are discharged into reef areas from the ballast of ships also pose a threat, especially when no predators or parasites for these introduced species exist in the host reef environment. One of the most noticeably damaging invasive species is the crown-of-thorns starfish of the Great Barrier Reef. This is a voracious coral polyp eater and is increasingly damaging reefs. Declines in predators of this spiny toxic starfish, due to over fishing and pollution have led to population explosions which is currently destroying huge areas of the coral reef.

Other Threats: In addition to those described above coral reefs are threatened by an array of challenges. These include SEDIMENTATION associated with coastal development and deforestation, DREDGING of reefs to create deep water channels and marinas and coral DISEASE. The occurrence of coral disease has increased dramatically in the past ten years, a likely combination of the threats discussed above and in parts 1&2.

CURRENT DAY THREATS TO CORAL REEFS: NATURE OR NURTURE? (PART 3).

Rising Sea Level.

Along with sea temperature increase, ocean acidification corals are also under threat from the rising sea levels associated with climate change. With a predicted sea level rise (of 6cm/ decade) the potential exists for reefs to ‘drown’ (i.e. be covered with such a depth of water that they are below the photic zone or otherwise connect calcify sufficiently to catch up with sea level), but this requires a protracted imbalance between reef accretion rates and sea level rise (Smith & Buddemeier 1992).  

Depending on water clarity and other environmental conditions, the depth range of maximum reef calcification may extend from several metre s to more than 20 metres. This depth range represents a safety factor; transient sea level rise may inundate oceanic reefs to a depth of metre s or even tens of metre s without terminating reef growth if sea levels  rise subsequently returns to a rate less than reef vertical accretion rates. A reef accretion rate of 10 mm/yr is commonly taken as the consensus value for maximum sustained reef vertical accretion rates (Smith & Buddemeier 1992). The predicted for sea level rise over the next century is on average 6 mm/yr (Smith & Buddemeier 1992); this is well within the range of reef accretion rates, and even with no net accretion sea level rise would submerge reefs by less than a metre  by the year 2100.

On the shorter time scale of years to decades, sea level is a changing environmental variable that may interact with other changes and be reflected in organism and community response. Because sea level has been within 1-2 m of its present elevation for several thousand years, many present-day reefs have grown to an elevation where further upward growth is constrained by sea level. Sea level rise can be expected to remove this constraint and result in increases in successful recruitment and coral longevity on intertidal and shallow subtidal reef flats, with a consequent increase in reef flat calcification (Smith & Buddemeier 1992). If rising sea level creates more benign conditions on shallow reefs, diversity and community structure may change as species other than the extremely hardy are able to survive. Increases in coral community diversity and productivity can also be expected in enclosed lagoons where salinity extremes, nutrient depletion, or other aspects of restricted circulation have restricted reef development (Smith & Buddemeier 1992), since the probable effect of rising sea level on circulation will be to maintain reef/lagoon water composition closer to that of the local oceanic water. On the other hand, if deepening water subjects currently sheltered communities to more physical (wave) stress, calcification and sediment accumulation may not increase.

Sea level rise is also strong associated with coral bleaching (Part 1) and associated mortality may selectively remove faster growing taxa, resulting in less rapid CaCO3 accretion and more rapid net removal of framework material by bioerosion.

References

Smith, S.V. & Buddemeier, R.W. 1992. global change and coral reef ecosystems. Annual review of ecological systems. 23: 89-118. 

CURRENT DAY THREATS TO CORAL REEFS: NATURE OR NURTURE? (PART 2)

A Review of Hoegh-Guldberg et al. (2007) CORAL REEFS UNDER RAPID CLIMATE CHANGE AND OCEAN ACIDIFICATION.

Introduction: Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by 2 degrees between 2050 and 2100. This significantly exceed conditions of the last 420,000 years during which most extant marine organisms evolved. Under expected conditions for the 21^st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems.

What is ocean acidification? During the 20th century, increasing atmospheric CO₂ concentrations has driven an increase in the global oceans’ average temperature by 0.74°C, sea level by 17 cm, and has depleted seawater carbonate concentrations and increased acidity by 0.1 pH units. Approximately 25% of the CO₂ emitted from all anthropogenic sources currently enters the ocean where it reacts with water to produce carbonic acid. Carbonic acid dissociates to form bicarbonate ions and protons, which in turn react with carbonate ions to produce more bicarbonate ions, reducing the availability of carbonate to biological systems (Fig. 1A). Decreasing carbonate ion concentrations reduce the rate of calcification of marine organisms such as reef-building corals, ultimately favouring erosion.

Figure 1: Links between the buildup of atmospheric CO2 and the slowing of coral calcification due to ocean acidification. 

Modeled scenarios: Hoegh-Guldberg et al. (2007) projected three scenarios for coral reefs over the coming decays and centuries.

1)      375ppc and 1˚C increase (stabilising at the present atmospheric CO₂ concentration) coral reefs will continue to change but will remain coral dominated and carbonate accreting in most areas of their current distribution (Fig 2A).

2)      However if we move towards higher CO₂ concentrations (450-500ppm and 2˚ increase) coral community compositions will change with some areas becoming dominated by more thermal tolerant corals and others potentially dominated by thermally sensitive but rapidly colonising genera. The density and diversity of corals on reefs are likely to decline leading to vastly reduced complexity and loss of biodiversity including losses of coral associated fish and invertebrates (Fig 2B).

3)      As atmospheric carbon dioxide levels of more than 500ppm are approached levels of carbonate ion concentrations fall well below today’s value and we exhibit an increase of more than 3˚ in sea surface temperature. These changes will reduce coral reef ecosystems to a crumbling frame work with few calcareous corals. Continuously changing climate (which might not stabilise for hundreds of years) is likely to impede migration of corals. Reefs will be rapidly eroded and ultimately become drowned reefs (corals and reef growth fail to keep up with rising sea levels). Under this climate scenario coral reefs become non-functioning (Fig 2C).

Figure 2: Extant reefs from the Great Barrier Reef that are used as analogs for the ecological structures under scenarious 1-3. A). reef slope communities at Heron island. B). mixed algal and coral community  & C). Inshore reef slope.

Impacts: These three scenarios are likely to have serious consequences not only on the corals reefs diversity and density but through wider regional economies e.g. coastal protection, fisheries, and tourism. These consequences become progressively worse as we move through the three potential scenarios.  

 

Conclusion: It is worrying to think that when using the lowest rage of IPCC scenarios there is still devastating effects for coral reefs. At carbon dioxide atmospheric concentration of more than 500 ppm the consequences for coral reefs are extremely risky for both corals and those that depend on them. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reef increasingly toward the tipping point for functional collapse.

*ppm – parts per million.