Pacific Bluefin Tuna, Overfishing, and the Anthropocene Defaunation

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Failure to Protect the Pacific Bluefin Tuna

A magnificent creature is going extinct before our eyes because it ranges far and wide across the Pacific Ocean, because it takes too long to grow up before it begins to reproduce, because it tastes far too good, and most of all because we are selfish, unwilling to relinquish the taste sensation or the buckets of money to be made in catching it. It is the Pacific bluefin tuna, Thunnus orientalis. IUCN listed it as ‘Least Concern’ in 2011, and have not yet seen fit to change their view. FAO reports it to be ‘Fully Exploited’ but otherwise scarcely mentions it in the 2014 State of World Fisheries and Aquaculture. The Inter American Tropical Tuna Commission (IATTC), which is supposed to be managing the catch in the Eastern Pacific, met in Lima, Peru, in July, and decided to punt until October, despite a clear recommendation from its scientific staff to reduce the catch in 2014 to no more than the tonnage caught in 2013 (3154 tonnes). (This compares to catches from the Eastern Pacific averaging about 10,000 tonnes per year in the period since 2000.)

PacificBlueTuna5918 CAS MacDonald

Pacific bluefin tuna, Thunnus orientalis, a high-speed, long-distance swimming machine.
Photo © CAS MacDonald

Across the Pacific, abundance of bluefin has fallen to about 4% of pre-fished state, and spawning stock biomass (literally the tonnage of adult fish) is at all-time lows. Recruitment of juveniles also seems to be bouncing along close to the minimum. About 90% of the fish taken are not yet mature – never the best way to harvest a population that is at very low numbers. But, of course, the science can always be questioned, and number of recruits is notoriously variable from one year to the next, so why should the catch be reduced until we are sure there is a problem? Then too, the numbers taken in the East Pacific are just a small part of the total and if catch is reduced there while fishing continues in the West Pacific all that has happened is the East Pacific fishers have lost money.
This is how we fish species to oblivion. By delaying action until we are absolutely certain that there is a problem. By assuming that the behavior of others (in the West Pacific) is the real cause of the problem. By being unwilling to step forward and do the right thing, because we do not want to lose even a tiny bit of income. By holding endless meetings in which we discuss but never reach a conclusion. The Pacific bluefin tuna is simply too tasty, and therefore, pound for pound too valuable to be allowed to continue to exist.

In the 1990 comedy, The Freshman, starring Marlon Brando and Matthew Broderick, the plot revolves around the clandestine Fabulous Gourmet Club, which meets in out-of-the-way venues to serve endangered species to wealthy guests. For a million dollars, you get to eat the last individual of a species going extinct. I remember watching, and thinking, this is not that far from reality! We value rarity, and willingly pay to possess it, whether it be fine art, fast cars, or bits and pieces stripped from the carcasses of rare animals – tiger whiskers, bear gall bladders, dried seahorses ground to a fine dust, rhino horn (also ground), shark fin, or a couple of slices of kuro- or hon-maguro sushi. Unfortunately, no matter how rare each species becomes, there is always somebody willing to acquire one more meal, one more fur, one more medicinal powder, and eventually another species bites the dust.


Matthew Broderick delivers a Komodo dragon to the Fabulous Gourmet Club.
Image © The Freshman, Tristar Pictures

In December 2012, I wrote of the plight of the Atlantic bluefin tuna, which is, if anything, closer to extinction than the Pacific species. What I wrote then about the sheer magnificence of this beast is true also of the Pacific Bluefin, and worth re-reading. So beautifully adapted to living on the high seas, a magnificent swimming machine, an engineering marvel that leaves me in total awe of the power of evolutionary change to sometimes achieve perfection, these are really the ultimate fishes. We are so privileged to share this planet with them that I find it hard to believe we are capable of willingly watching ourselves fish them to extinction. And yet we are. Because they taste too wonderful.

There had been outside pressure on IATTC to act. The Pew Charitable Trust had called upon members, prior to their July meeting, to act decisively on Pacific bluefin tuna because of its perilous status. Predictably, the failure of IATTC to act was met with considerable outrage and high dudgeon. The EU representative was annoyed that nothing much happened at the meeting, but reports suggested the annoyance was more with failure to act on a whole host of items (such as election of a new Director) that the EU favored, rather than specifically at the lack of action on bluefin. The WWF was critical of the failure to act, and has said it will call for a cessation of the fishery if IATTC fails to act in October, and Amanda Nickson, director of global tuna conservation work by the Pew Charitable Trust, was quoted as saying after the meeting,

“Once again, fishing nations have ignored the scientific evidence before them and will allow this decimated population to continue to be overfished, despite dire warnings that it is on the edge of collapse. Pacific bluefin tuna needs an oceanwide recovery plan. This lack of action shows that a suspension of the Pacific bluefin tuna fishery may be the only way to save this species.”

I do not see a suspension of the fishery occurring any time soon. Not until a far greater proportion of humans begins acting ethically instead of selfishly. Nor do I see this case as an isolated instance. We are currently causing an unprecedented thinning out of biodiversity across the planet.

The Anthropocene Defaunation

In the 25th July issue of Science, Rodolfo Dirzo of Stanford University, and five colleagues from the USA, Brazil, Mexico, and UK, published a chilling article, Defaunation in the Anthropocene. In it, they review anthropogenically driven loss in biodiversity since 1500, choosing that year as the start of the Anthropocene, that period in Earth history in which humanity is a major force for planetary change. Their results are not surprising, but they should be concerning. In the past 500 years, humanity has triggered a wave of reduction in abundance, extirpations of populations, and extinction of species that may rival anything seen in any of the five great mass extinction events in Earth’s history. Since 1500, 322 species of terrestrial vertebrates have become extinct, and populations of the remaining species show 25% average decline in abundance.

Invertebrate patterns are equally dire: 67% of monitored populations show 45% decline in mean abundance. (Not mentioned in their article, our impacts on the ocean have been just as severe, with a 90% reduction in biomass of marine fishes commonly cited as the result of our over-enthusiastic fishing.)

As Dirzo and colleagues make clear, while the extinctions, particularly of large, charismatic species, capture the attention, it is the pervasive losses in abundance and reductions of range of individual species that are the most important consequence ecologically. Fewer individuals are available, in fewer places, to play the ecological roles they used to play.

In fact, if we think carefully, most of us can remember a time when there was more life on this planet (and I am not referring to the 1960’s, although they were lively). I particularly remember that back in the days when all gas stations were full service, part of that service was getting your windshield washed. A capable attendant could get the nozzle going, filling your gas tank, and then have time to wash and squeegee your windshield clean before he had to get back to close the tank, hang up the hose and collect your money. Sometimes you got additional cleaning of headlamps and so on. What I particularly remember, back in the day, was that travel in the country, rather than the city, sometimes made it necessary to stop at a gas station before you needed fuel, because you needed your windshield cleaned.

1959 LVC Lambda La Verne Chevron Service

Gas station attendants gave personalized service back in the day. Image © Old Towne Laverne Blog

Flying insects, particularly the big ones that managed to go splat right in front of your steering wheel, were so abundant that the windshield cleaning courtesy was far more than a courtesy. It was a necessity for safe travel. Today, I can drive for hours through farming country and pick up no more than two or three modest little bugs. People of a certain age who watch birds, and particularly those who watch and keep a journal, can tell numerous tales of birds that used to be common but are now seldom seen. In my part of the world, I find the question, ‘have you heard a whip-poor-will lately?’ an effective way to get people thinking about the losses that have taken place. Because this iconic call, that always told a much younger me it was summertime in Ontario, is a call I have not heard for years. The bird is not extinct in Ontario, but it is completely absent from large swaths of former territory.

Dirzo et al Fig 1 large

Four examples from the article by Dirzo and colleagues show the losses in biodiversity being caused by humanity worldwide. A) Large fractions of all the insect species monitored by IUCN are currently declining in abundance. B) Records for British insects of four Orders show from 30 to 60% of species are becoming less widely distributed. C) Globally, an index based on invertebrate species abundance shows that moths and butterflies have declined less severely than other types of invertebrate. D) A meta-analysis of studies of moth and butterfly diversity show the overwhelming majority of disturbed areas hold a reduced biodiversity of these insects. Figure 1 © R. Dirzo, Science

Dirzo and colleagues make the important point that while deforestation is a well-understood term, and an event that is readily apparent and quantifiable in aerial photos of landscapes, defaunation is a far less familiar process to people, and essentially invisible until detailed monitoring studies are undertaken. (Or until someone asks if one has heard a whip-poor-will.) Yet both defaunation and deforestation are vitally important ecologically. They discuss the patterns in defaunation, noting that species are differentially susceptible, and that extent of defaunation varies geographically as well. Among vertebrates, the amphibia have proven particularly susceptible, perhaps because of their dependence on water in the landscape and their sensitivity to chemical pollution. Among mammals, the larger species tend to be most impacted; indeed, mammal faunas show a clear pattern in which the largest-bodied species became extinct by the end of the Pleistocene, a next-largest cohort became extinct in recent years, a next-largest cohort of species is currently threatened and in reduced numbers, and the smallest-bodied cohort seems relatively less affected by us. In general, defaunation has also proceeded more rapidly in the tropics, partly because this is where most species occur, but also because this is where human activities have had the most profound impacts on natural habitats.

Dirzo et al Fig 3 large

Distribution of adult body size varies among mammal species that became extinct during the Pleistocene, became extinct more recently, are currently considered as threatened with extinction, or are currently considered not to be threatened.  Anthropocene defaunation is making mammalian faunas smaller in stature. Figure 3 © G. Dirzo, Science

The main strength of their article, however, is not in how it enumerates the losses of species or reductions in population range or abundance. Dirzo and colleagues summarize the several ecological consequences of this simplification of the biosphere. These include pollination, pest control, nutrient cycling and decomposition, maintenance of water quality, impacts on human health, and the distinct possibility that our defaunation is shaping the evolution of ecological systems in ways that may or may not be to our advantage.

I commented on pollination issues in this blog in April 2013, and attention to the declining abundance of bees has, if anything, grown since then. Neonicotinoid pesticides are among the new weapons we are attacking bees with, and the seed and pesticide agribusinesses are playing the ‘evidence does not absolutely confirm neonicotinoids are to blame’ game used by every business on the planet that wants to continue with practices that obviously damage the biosphere. Dirzo and colleagues simply state that 75% of all our crop plants require insect pollinators, and that the pollination service is estimated to be worth 10% of the economic value of our global food supply. They then report that pollinators appear to be declining strongly, both in abundance and diversity, across the globe.

Small vertebrates play a major role in controlling the abundance of smaller, usually insect or other invertebrate, pests. Experimental or observational studies have found that removal of small vertebrates from a site leads to a broad range of adjustments to the composition of the animal community as prey species become more common, and inflect more damage on plants or their own prey organisms. Such ‘trophic cascades’ are a feature of any ecological system that is disturbed by removing an important predator. Dirzo and colleagues report that arthropod (mainly insect) pests are typically responsible for destroying 8 to 15% of crop yields, and that reduced abundance of small vertebrates could see this damage rise to 37%. In North America alone, they peg the value of pest control by small native vertebrates at $4.5 billion annually.

Comments in the article on effects on human health were particularly chilling. Defaunation, by reducing diversity, reduces the provision of numerous goods and services, including sources of pharmaceutical compounds, biocontrol agents, food resources, and disease regulation. Between 23 and 36% of all birds, mammals, and amphibians used for food or medicine are now threatened with extinction. In addition, wildlife provides important food resources in many societies, and loss of abundance deprives people of needed food. One estimate suggests loss of wildlife in Madagascar will lead to a 30% increase in anemia with resultant increases in mortality, morbidity and learning difficulties. While Dirzo and colleagues stuck to terrestrial fauna, the collapse of coastal artisanal fisheries is increasing the challenges for the very poor in many tropical countries, yet current trends suggest we are proving inept at preventing this degradation.

Dirzo and colleagues end their review with a warning that “cumulatively, systematic defaunation clearly threatens to fundamentally alter basic ecological functions and is contributing to push us toward global-scale ‘tipping points’ from which we may not be able to return.” Then, they plead for a more meaningfully attack on “immediate drivers of defaunation” stating that

“mitigation of animal overexploitation and land-use change are two feasible, immediate actions that can be taken. These actions can also buy necessary time to address the other critical driver, anthropogenic climate disruption. However, we must also address the often nonlinear impacts of continued human population growth and increasingly uneven per capita consumption, which ultimately drive all these threats (while still fostering poverty alleviation efforts). Ultimately, both reduced and more evenly distributed global resource consumption will be necessary to sustainably change ongoing trends in defaunation and, hopefully, eventually open the door to refaunation.”

I came away feeling that their recommendations for action were unlikely to achieve very much, and that until people realize the true extent of the 6th mass extinction, we are unlikely to change our ways. But then, that is true for virtually every aspect of the global environmental crisis we face. Until a sufficient number of us wake up and look around, nothing much is going to get done and the problems will continue getting worse. Surely that sufficient number must be just around the corner?

forest fish bee reef

We will find our way once we comprehend that the trees are worth more than the timber, the bluefin are worth more than the sushi, the bees are worth more than the honey, and the reefs are worth more than the limestone.

Categories: Biodiversity Loss, Fisheries, In the News | Leave a comment

Cumulative Effects, Synergistic Stressors, and the Decline of Coral Reefs

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The Coral Reefs of the Caribbean

Dr. Thomas F. Goreau, who died in 1970 at just 45 years age, was a pioneer coral reef ecologist who began studying the reefs of Jamaica in 1951.  A faculty member at the University of the West Indies, he established the Discovery Bay Marine Lab, which still operates on the mid north coast of the island – one of the oldest research facilities in the Caribbean.  Many reef scientists got their start as graduate students working at Discovery Bay, and some of these have gone on to make great contributions to coral reef science in their own right.  One of these, Dr. Jeremy Jackson, just published a report on the decline of Caribbean coral reefs.  But I am getting ahead of myself.

In 1959, Tom Goreau published an article in the journal Ecology, titled “The ecology of Jamaican coral reefs, I. Species composition and zonation.”  It was illustrated with gorgeous underwater and aerial photographs that are unfortunately grainy messes in the pdf versions of his paper that I can now download from the web.  They are photos of another world in two very real senses – a world so very different to the high-and-dry world that most of us inhabit all our lives, and an underwater world totally unlike that at any location that now exists in the Caribbean.  It was a world of magnificent coral architecture stretching for miles along the coast of Jamaica.

Coral reefs grow in a more-or-less typical form  comprising at its simplest, a wide but very shallow reef flat with some living but lots of dead coral, a reef crest, the highest point facing the breaking waves, and a reef slope that may be divided into several zones covering different depths.  In the beginning, which for coral reef science means the mid-20th century, corals were so abundant on typical Caribbean reefs, that when people like Tom Goreau set out to describe reefs, they gave names to most zones in the structure of the reef based on the dominant coral species present.  Thus, Goreau recognizes the ‘reef flat’ or Zoanthus zone, the palmata zone, the buttress zone, the cervicornis zone and the annularis zone.  Goreau wrote of the palmata zone:

In the upper, or breaker, region of this zone, the Zoanthus overgrown reef flat abruptly gives way to a narrow zone which is populated almost exclusively by huge tree-like colonies of Acropora palmata that take the full force of the surf.  The great serried outliers of this coral are predominantly oriented in the direction of the prevailing seas which thus give the whole zone the characteristic appearance of a great jagged comb with irregular teeth. ….. In front of the breaker zone, the reef slopes gently downward to depths of between 5 and 6 meters. …..  Acropora palmata is still the dominant coral, growing in large isolated heads that also are strongly oriented into the prevailing seas.”

A palmata by sailn1-flickr

Imagine miles of reef front composed of a magnificent rampart of Elkhorn coral (Acropora palmata), a species now on the Endangered species list.  Goreau’s reefs no longer exist.  Photo © sailn1/flickr

Notice his phrasing – “huge tree-like colonies,” “great serried outliers.”  Elkhorn coral (palmata’s other name) can indeed be giant and tree-like, with stout branches as big around as a human arm or leg, soaring upwards before fanning out to create archways as much as one to two meters high, and sometimes spacious enough that a careful diver can squeeze in between.  Treelike indeed, and in great serried ranks stretching along the coast as a giant barrier protecting the shore from incoming waves.  Elsewhere in the article, Goreau refers to “the extensive proliferation of Acropora palmata that is so characteristic of the upper zones of West Indian reefs.”  He also talks about the buttress zone having its surfaces almost 90% covered by living corals, and refers to the “immense beds of staghorn coral, Acropora cervicornis” that typify the “cervicornis” zone.  From his words and his pictures comes a clear picture of a place dominated by colonies of living corals, a living architecture that provides the background to the lives of all those other creatures one expects to find on a coral reef.

Several of the scientists featured in Reef Reminiscences describe the Caribbean reefs they remembered, using similar phrases, and Judy Lang remembers her time at Discovery Bay as a young graduate student working with Tom Goreau.

Fast forward to 2014, and the new IUCN publication authored by Jeremy Jackson.  It begins by quoting well-known senior marine scientist, Sylvia Earle, who wrote in 1972:

Perhaps the most striking aspect of plant life on a coral reef is the general lack of it.  It seems anomalous to even the casual observer that tropical reefs, notable for their dazzling profusion of animal life, are almost devoid of conspicuous plants.

It then states, “Sylvia Earle’s early observations upon Caribbean reefs describe a forgotten world. Caribbean coral reefs have suffered massive losses of corals since the early 1980s due to a wide range of human impacts including explosive human population growth, overfishing, coastal pollution, global warming, and invasive species.  The consequences include widespread collapse of coral populations, increases in large seaweeds (macroalgae), outbreaks of coral bleaching and disease, and failure of corals to recover from natural disturbances such as hurricanes.”

Status and Trends Caribbean 2014

Cumulative Effects

Welcome to the world of cumulative effects.  That phrase refers to the fact that different stressors acting on an ecological system have a total effect that is larger than the effect of any single stressor.  For example, the impact of one hurricane on an otherwise healthy coral reef will be some degree of physical damage, the extent of which depends on storm intensity, tidal phase and direction of storm travel at the time of impact.  That damage can be repaired by regrowth of corals in following years.  A succession of hurricanes of similar strength, hitting the same reef over a several year span will cause greater damage, and might even hammer the reef to rubble – each successive storm will further damage an already damaged reef structure.  Similarly, if a reef is subject to pollution from coastal agriculture, damage will be caused, and a hurricane will further damage this reef.  In each case there are cumulative effects.

Sometimes the cumulative effects are no greater than the sum of the impacts of each of the stressors, but the stressors may also act synergistically, meaning that one affects the degree to which the other has impacts.  For example, the pollution may weaken the reef, making it more susceptible to the physical damage caused by storms than it would otherwise be.

Caribbean and all other coral reefs have been suffering cumulative effects of human activities for a long time.  Overfishing removes organisms with important ecological roles, such as the parrotfishes that graze algae and scrape away at dead and living corals to generate newly exposed, clean rock surfaces that may be particularly suitable settlement sites for new coral larvae.  Pollution from domestic and agricultural run-off adds nutrients that favor growth of algae that may in turn smother corals, shade them out and ultimately kill them.  The pollution may also make the corals more susceptible to diseases.  Destruction of reefs through inappropriate coastal development, fishing using traps or explosives, anchor damage, and coral mining for use in construction projects, may further damage already damaged reefs, or may happen at rates that exceed the reef’s capacity to repair itself through new coral growth.

The story of Caribbean coral reefs is a textbook example of cumulative effects in operation, and the depressing results are there for all to see.  Jackson and colleagues report the results of a careful analysis of the various monitoring data from across the Caribbean and from the early 1970s until now.  Despite differences among data sets in data quality or sampling methods that make an analysis much more difficult, they have been able to develop a reasonably precise estimate of the extent to which coral cover has declined, and to examine the different patterns of decline from place to place across the region.  Coral cover across the region, based on the most recent data available is now on average 14.3%.  Abundance of various fleshy algae (nearly absent in Goreau’s time) has grown to an average of 24% coverage of the reefs over the same period.  Coral cover has declined from an average of 34.8% during 1970-1983, to 19.1% during 1984-1998, and to 16.3% during 1999-2011.  The variation among locations is large, both in pattern of decline through time and in overall extent.

As the graphs below show, the pattern of decline was steep prior to 1984 for nine well-studied locations from the Dry Tortugas to Costa Rica including five sites within Jamaica, with little change after that time (Graph A).  The decline was almost linear across the full time period at five other locations in the Virgin Islands, Mexico and the northern Florida Keys (Graph B), and was essentially non-existent at seven locations, five along the southern boundary of the Caribbean and one each at the Flower Gardens Bank in the northern Gulf of Mexico and at Bermuda well to the north.  Clearly, the loss of coral cover has not been uniform across the Caribbean.

Status & Trends Fig 4 A-C

Status & Trends Fig 4 D resize

Figure 4 from the IUCN report, Status and Trends of Caribbean coral reefs, 1970-2012, showing in Graphs A, B, and C the different patterns of coral loss at 21 well-studied sites located at the sites shown across the Caribbean.  Image © IUCN.

The lack of consistency in pattern is not surprising.  The relative intensity of such stressors as overfishing, pollution, and physical destruction varies from place to place, and the reefs themselves are in different oceanographic settings – close inshore, near a polluting river mouth, bathed by clean oceanic water, facing or protected from prevailing winds.  The cumulative effects, not surprisingly, also differ.

The report evaluates the various stressors, and possible interactions among them.  For example, certain coral diseases have been of major importance in Caribbean reef decline, and have virtually wiped out Elkhorn and Staghorn coral (they are both on the US EPA Endangered Species List).  There is some scientific evidence suggesting synergy: diseases appear to have been facilitated by the exuberant growth of algae and/or by pollution.  This is also the first major report I have seen to make the case that in some places tourism has had significant negative effects on reefs.  Overfishing is particularly interesting, because it may be that the removal of important grazers, particularly the parrotfishes, has facilitated the growth of algae that in turn has contributed to the loss of coral through competition for space on the reef, and inhibition of settlement of new coral larvae.  The effects are not only cumulative, there are many of them and they seem to be interacting in complex ways.  Naturally, the chief cause of coral decline in the Caribbean is our growing numbers, and growing desire to live near, and make use of reef systems.

One result that is at first surprising is that, in the Caribbean, bleaching and subsequent coral death due to the warming of climate change has been of less importance than several other stressors.  There is no doubt that bleaching damage has been important at some locations, and scientists expect that bleaching, together with ocean acidification, is going to become a more important stressor over the next decades as we further warm up the climate, but up to now it has played only a small role in this part of the world.

Dumbing Down the Story

The IUCN report does a generally good job of reviewing the evidence for each of the stressors in turn, and makes the point clearly that Caribbean coral decline has been a complex process with multiple causes that vary a lot from place to place.  Unfortunately, when it came to writing the summary for the report, and even more so, when it came to writing the press release, the people at IUCN made the common mistake of dumbing down the results, focusing on only a couple of stressors, and suggesting (unless the words are read very carefully) that all we have to do is to begin protecting parrotfishes and coral reefs will recover.  Naturally, the media dumbed the message down even further – coral reefs are degrading because we have been overfishing parrotfishes.  And the climate change deniers grabbed the few sentences on climate change to trumpet that the worldwide decline of coral reefs had everything to do with overfishing parrotfishes, and nothing to do with CO2 pollution.

Global Coral Decline

So let me say it once more.  Cumulative effects are real.  The global decline of coral reefs is a classic example of the consequences of cumulative effects, and has different causes from place to place.  In the Caribbean, climate change induced coral bleaching has been one of the causes, but not a major one until now.  A number of other factors have been more important there until now.  These include the overharvesting of parrotfishes, and if we begin protecting parrotfishes that should be helpful.  Paradoxically, if the many marine protected areas (MPA) throughout the Caribbean had been properly managed, so that fish within their boundaries largely escaped fishing pressure, we would be able, today, to see the extent to which protecting parrotfishes could help reefs.  Instead, of course, most Caribbean MPAs are only really protected on paper, as are far too many MPAs around the world, and fish inside their borders suffer from overfishing just as do fish living outside their boundaries.

I’ve written before about the report in Science in 2012, in which Glenn De’ath and colleagues used a 27-year long data set to evaluate extent and causes of change in coral cover on the Great Barrier Reef.  Their results were equally as depressing as those in Jeremy Jackson’s IUCN report.  Cumulative effects were again in evidence, but the three main stressors were cyclones (hurricanes), outbreaks of the Crown-of-Thorns starfish which feeds on living coral, and bleaching due to climate change.  I earlier discussed how humans had a partial role in two and perhaps all three of these.

These relatively recent results for the Great Barrier Reef and the Caribbean represent the two best surveys of coral decline over large geographic regions.  There is nothing to my knowledge to suggest that most other regions of the world are not suffering similar patterns of coral decline, and I anticipate that cumulative effects are evident in every location.

There is one more thing to say before leaving this topic.  If we want to restore coral reefs, in the Caribbean or anywhere else, we have to take action to reduce the impacts of at least some of the stressors acting.  We have to take real action, not plan to take action, not pass legislation or write new regulations.  We have to actually take action to alter our behavior around reefs.  This is good news!  Because it means there are actions we can take that will make a difference.  It’s not rocket science, but it does take a real commitment.

We have a serious problem that can be mitigated if we want to do so, because most of the stressors act locally.  While it is going to require major international action to reduce CO2 pollution, better regulation of fishing, of pollution, of coastal development, and of tourism can all be done locally, on single stretches of coast, where the community and the government want to make a difference.  It’s a serious problem, but a very fixable problem!  But not fixable if we only pretend to act, or if we grab at one cause only and run around telling people that saving parrotfishes will save the reefs.  It is really time now to get real.  Do we really want to save some of the world’s coral reefs?

Adding to the Cumulative Effects

One thing we should not be doing is adding to the cumulative effects.  Unfortunately, in Australia right now that is precisely what government action seems destined to do.  Australians value their Great Barrier Reef.  It is well managed at considerable annual cost, and it generates far more than it costs in the tourism it drives year by year.  It is a UNESCO World Heritage Site, recognized around the world.  I thought it was in safe hands.

This was not always the case, and I describe in Our Dying Planet how Australians changed their attitude to the reef and to the environment in general during the mid-70’s, all because a tiny NGO called the Queensland Littoral Society produced a bumper sticker with the slogan, Save the Barrier Reef.  That slogan led ultimately to legislation banning oil prospecting over reef waters, and to the formation of the Great Barrier Reef Marine Park and the Federal Agency that manages it in close cooperation with the Queensland state government.  I have long claimed the Great Barrier Reef to be the best example of reef management in the world.  It has a strongly science-based management process.  Among notable achievements, it now has 33% of its area protected as no-take fishing exclusion zones, and managers have been able to work with agricultural interests to modify the farming practices along the length of Queensland to reduce fertilizer and pesticide run-off and restore water quality for reefs hundreds of kilometers away from the nearest sugar cane fields.  That kind of reach beyond the borders of the area of jurisdiction is very rare in the world of marine protection.


A bumper sticker which saved the Great Barrier Reef in the 1970s.  Image © AMCS

But Australia is also a nation rich in coal and other mineral deposits and resource exploitation and export is a major component of the economy.  A significant battle has been going on over the past few months because the ‘need’ to expand port facilities to export more and more coal to China has run up against the need to protect the Great Barrier Reef.  The change of government, late last year, bringing a climate change dismissing (if not denying) government to power in Canberra has tilted the playing field back in the direction of coal and away from conservation.  In unrelated legislative activities, Australia has just cancelled its carbon tax – a backward move that may be substantially more serious than Canada’s abrupt withdrawal from Kyoto several years ago.

I started noticing media reports at the start of 2014.  An article in the Sydney Morning Herald for 4th February reported that plans called for an increase in coal exports from 240 million tonnes in 2013 to 787 million tonnes in 2030.  To do this will require expanded and new shipping terminals along the Queensland coast – and that means inshore of the Great Barrier Reef.  A report released by the Australian Marine Conservation Society early in 2014, Dredging, Dumping, and the Great Barrier Reef, identified nine port construction or expansion projects being planned.  While the dredging planned at Cairns is in order to permit entry of larger cruise ships, the others all relate to the coal export industry.  They range from Cape York in the far north of the reef to Gladstone at its southern end – they could not be more widely distributed along its shoreward side if they had been explicitly designed to be so.  The report estimates a total of 83 million m3 (or 149 million tonnes) of material to be dredged and then dumped offshore, but still within the Great Barrier Reef region (there is lots of open space between and inshore of the reefs).  The Guardian commented on the situation on 7th May, drawing attention to the mining industry’s claim that coral decline has been caused by bleaching, Crown-of-Thorns, disease, and cyclones (quoting De’ath’s article), and inferring therefore that dredging does no damage (the logic of mining companies is sometimes a bit shaky).  Dredging planned for the future is not going to show up as a cause of coral decline in the past unless Australia exists in a really unusual universe!  The Guardian article also mentioned a study of effects on corals of smaller scale dredging at one of the ports, and the inadequacy of the methods used to assess possible damage – needless to say, the mining industry quite likes to reference these inconclusive data.

New Scientist for 26th May carried a short article by Dr. Jon Brodie of James Cook University that looked specifically at one port – Abbott Point, currently the most northerly coal port on the Queensland coast, located 25 km north of the town of Bowen, and slated for expansion requiring 5 million tonnes of sediment to be dredged and dumped further offshore (but still inside the reef).  Brodie notes that when the plan was announced, the Environment Minister, Greg Hunt, stated that the project would not reduce water quality over the reef.  This is because the approval requires that the impacts due to sedimentation by the dredged material be ‘offset’ by improvements to agricultural practice to reduce sediment run-off in two nearby rivers.  As Brodie noted, to fully offset the delivery of 5 million tonnes of sediment requires that the waters of those rivers must have their sediment loads cut by 5 million tonnes of sediment.  Unfortunately, they carry only 6 million tonnes a year, so cutting that by 5 million becomes “a tall order”.  I’d call the pretense that this is a solution a tall tale.

Recently, a post on coral-list by Dr. Terry Hughes of James Cook University alerted me to two recent articles from that institution that are relevant to the issue.  The first, by Joe Pollock and seven colleagues from James Cook University, Australian Institute of Marine Science, and other institutions in Western Australia and Queensland, was published in the open access journal, Plos One, on 16th July.  Their study, funded as part of the required environmental impact assessment process, was a detailed study of coral health and survivorship at different distances from a sediment plume caused by dredging for another resource development project, the giant Gorgon gas project on the Pilbara coast of Western Australia.

Fig 1 Pollock resize

Figure 1 from Pollock’s article showing the incidence of diseased (red) or compromised (green) corals at sites exposed to the sediment plume and at sites away from the plume.  Numbers indicate number of days exposure to sedimentation.  Image © Plos One

Dredging for that installation amounted to some 7.6 million tonnes of sediment over an 18 month period from May 2010 to November 2011.  Their results show clear impacts of the sediment plume on coral health.  Primarily, corals exposed to the sediment plume suffered greater incidence of a suite of coral diseases.  In addition, the prevalence of a number of other morbidity factors was increased.  Tissue necrosis was 57 times more likely at sites within the sediment plume, and bleaching, overgrowth by sponges, and changes in pigmentation also increased.  Their conclusions are quite explicit:

This study provides the first empirical evidence linking turbidity and sedimentation with elevated levels of coral disease and other indicators of compromised coral health in situ.  We found two-fold higher disease prevalence, largely driven by increases in [‘white syndrome’, a common disease], and six-fold higher levels of other compromised health indicators at high sediment plume exposure sites.  Since these in situ health assessments were conducted more than 18 months after commencement of dredging, it is likely that the most susceptible corals experienced complete mortality prior to surveys being undertaken.  Therefore, these prevalence figures likely underestimate the true impact of dredging-associated sedimentation and turbidity on coral health”.

The second study, by Kathryn Burns of James Cook University, was published in Estuarine, Coastal and Shelf Science, and directly concerned the sediments being dredged within the Great Barrier Reef.  She examined samples of the sediments, and of material collected from the sediment plume caused by dredging at Hay Point, off Mackay, Queensland.  Looking for PAHs (polynuclear aromatic hydrocarbons – some of the nastier chemicals out there) she found ample evidence that PAHs derived from coal dust were in the sediments being deposited from the plume well out to sea and towards the outer Great Barrier Reef.  Her conclusions were also explicit:

The data shown here demonstrate that the coastal sediments offshore of the Hay Point coal port are already contaminated with coal residues which exceed the ANZECC/ARMCANZ (2013) toxicity guidelines and approach toxicity values under the US EPA guidelines.  If the US EPA guidelines had included the biphenyl and dibenzothiophene series which are also present in samples then calculated toxicity values would have been higher…”

Putting this all together, we have evidence that extensive dredging is going to damage the Great Barrier Reef through impacts on water quality, and that turbidity, smothering due to sedimentation, and noxious chemicals all play a role.  But we also have evidence that the industry and the government want to expand those coal ports, and are willing to claim there will be no damage to the reef.  The Australian government is playing the same ‘economy’ and ‘jobs’ cards being played by the Harper government in pushing expansion of Canada’s tar sands industry.  And the science and conservation community are doing their best to be heard.

Let’s Close with Some Good News

On 24th May, we learned that the HSBC bank had followed the lead of Deutsche Bank, and decided not to fund the expansion of port facilities at Abbot Point, citing unacceptable social, environmental and financial risks to investors.  Put into plain English, neither bank wants to risk its reputation by investing in a project that will damage the Great Barrier Reef.

On 20th June, Reuters reported that the Dudgeon Bay project, a new port facility near Hay Point intended to handle 180 million tonnes of coal a year, had been put on hold indefinitely.  The developers claimed that lower than anticipated prices for coal meant that demand for export facilities would not be sufficient to justify the expense.  It’s also possible they were just getting cold feet.

I do not, for one moment, believe this battle is over yet.  A number of port expansions remain in play, and the Australian government has certainly not seen any reason to slow down the rush to dig up and export every thing of value from Australia …. Boy, that does sound a lot like Canada, doesn’t it!

However, there is one more tiny bit of good news.  That tiny NGO, the Queensland Littoral Society, with its simple slogan, Save the Barrier Reef, that really did save the Great Barrier Reef back in the 70’s…. it changed its name a few years ago, and is now the Australian Marine Conservation Society.  It’s the same people!  You can read about its history on its web-site while you download its report on dredging.  It is still out there, saving the barrier reef.  With that kind of long-term commitment and dedication, and with the efforts from the science community to get the truth out about likely impacts, there is a good chance the reef can be saved yet again.

Putting this news about the Great Barrier Reef together with the story of coral decline in the Caribbean, I feel strangely invigorated.  Even though the threats due to climate change and ocean acidification still hang over coral reefs worldwide, there are many other stressors acting, and most of these are local.  It is possible to make a real difference now, by acting on each of these local stressors, by cutting pollution and by saving parrotfishes, by curtailing unwise coastal development and regulating tourism firmly.  A good start might be simply to protect all those unprotected MPAs around the world, while speaking out forcibly about any new projects to add to the difficulties faced by coral reefs.  Cumulative effects require cumulative efforts to stem the tide and prevent us from killing the reefs.  They are worth caring about.

A palmata by seestjohn-com

Fish sheltering under Elkhorn coral, St. John, USVI.  Photo © Gerald Singer

Categories: Climate change, Coal, coral reef science, Fisheries, In the News, Our Dying Planet, Politics | Leave a comment

Our Changing Climate and its Economic Impacts

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We are suffering a fever.  Month after month, this old planet just keeps getting warmer.  Not actually hotter month by month – we still have summer and winter.  But each month is usually a little bit warmer than it was a few years ago at the same month.  Despite the cold episodes in our winter here in eastern Canada and the long slow start to Spring, when they average in our temperatures with those from the rest of the world, the NOAA scientists report a much warmer than usual year.  If things continue this way through the northern summer, we could see some significant damage to coral reefs due to coral bleaching both in the Caribbean and in South-east Asia.

MAr-May 2014 global temp NOAA

On this map showing temperature anomalies as percentiles for the March to May period, eastern North America stands out as the only substantial land area with temperatures cooler than usual for this time of year.  Image courtesy of NOAA National Climatic Data Center.

NOAA’s global report for the month of May reports May 2014 was the warmest May on record averaging 0.74oC above the average for the 20th century.  This was primarily due to warm ocean temperatures; when they examined land temperatures only, this May was only the fourth warmest.  Looking further back, the global average temperature for the March to May period was the second warmest on record behind that for 2010.  The March to May map shows how eastern North America was clearly doing a very different dance to the rest of the world, remaining cooler than average while virtually every other land area on the planet was warmer or much warmer than average.  Australia, which had had a warm summer continued with its warmest May ever, while Alaska recorded its sixth warmest May.

The NOAA climate scientists are still declaring an el Niño event has about a 70% chance of starting in the next few months, and an 80% of commencing by later this Fall.  I think we are probably headed for a warm Fall and Winter.  Of course, that is ‘we’ globally.  There remains the chance that some portion of the globe, like eastern North America might do its own thing as it did last winter – you can always depend on the weather (rather than climate) to be undependable!

Economic Costs of Climate Change are Starting to be Recognized

While there remain plenty of climate change deniers out there, national governments and the business community are beginning to think about the economic costs of climate change.  It’s funny to me that we have abundant evidence of serious environmental consequences of climate changes now occurring, but these do not seem to grab the attention of governments and business.  Somehow, economic costs seem so much more real than environmental ones.  Still, at least they are starting to recognize the substantial costs of continuing business as usual, and that is far better than sitting dumbly assuming that nothing out of the ordinary is happening.

One action that got media attention was an Op-Ed in the New York Times on June 21st by former US Treasury Secretary, Henry Paulson.  He stated that we are “staring down a climate bubble that poses enormous risks to both our environment and economy. The warning signs are clear and growing more urgent as the risks go unchecked”.  In Paulson’s view we, meaning the US, has got to act and soon.  His preferred approach?  A carbon tax.  He says that failing to act on carbon pollution will be catastrophic: “With [the 2008 financial collapse]  indelibly affecting my perspective, viewing climate change in terms of risk assessment and risk management makes clear to me that taking a cautiously conservative stance — that is, waiting for more information before acting — is actually taking a very radical risk. We’ll never know enough to resolve all of the uncertainties.  But we know enough to recognize that we must act now”.  A dyed in the wool, senior Republican who clearly gets it.

I also saw an interview in with Mike Robinson, VP of Sustainability at General Motors, concerning GM’s recent signing of the Climate Declaration, an advocacy device organized by Ceres to bring businesses and individuals to lobby the US government to take action on climate change.  The list of names is interesting; GM is certainly the largest corporation on board.  And, gee whiz, there do not appear to be any fossil fuel companies to be seen!


The Climate Declaration and the companies that had signed on by late June.
Image from

OECD’s New Report on the Global Economy

The OECD is an international, business-friendly organization.  It has just released a report, Policy Challenges for the Next 50 Years, forecasting the global economy through the next several decades.  In typically positive, upbeat fashion, it tries to put the best spin on a global economy that has been stumbling about since the 2008 crash.  Still, it is forced to admit that GDP growth will decline over the next 50 years and that income inequality will become greater.  OECD has a remarkably conservative view of the likely impact of climate change, simply stating that “rising greenhouse gas concentrations pose the most comprehensively global risk to economic output”, and then going on to say, “while the full effects of unfettered GHG emissions are expected to produce their largest economic damages after 2060, rising global temperatures may start to affect GDP earlier.”  A couple of paragraphs later they estimate that global GDP might be reduced by between 0.7 and 2.5% by 2060.  They clearly don’t see climate change as anything to worry about just yet.  Do the authors pay any attention to environmental woes, or the costs of environmental crises that are happening around the world right now?

What I did find interesting is that the OECD report drew attention to their previously published estimate that a broad effort to mitigate CO2 pollution could yield a 6% boost to the global economy, partly because there exist some 550 different measures encouraging production of fossil fuels, amounting to $ 90 Billion (in 2011), and in addition, there are measures encouraging use of fossil fuels in various emerging and developing countries that together amount to $ 544 Billion (2012 data).  It seems a no-brainer to shift away from fossil fuels as quickly as possible, but as we all know, forging a comprehensive global climate treaty is not proceeding very well.

A New Way Forward to Break the Impasse in Climate Negotiations

This conveniently lets me turn to another article.  Writing in the journal Nature Climate Change, Marco Grasso, Università Milano-Bicocca, Italy, and J. Timmins Roberts, Brown University, Rhode Island, provide a perspective on how to move the negotiations for the climate treaty forward.  In A Compromise to Break the Climate Impasse, they suggest 1) initially limiting negotiations to a group of just 13 countries (actually 12 plus the EU) that together account for 81% of total cumulative emissions since 1990, 2) using national rates of consumption of carbon rather than rates of production to determine relative responsibility, 3) taking both responsibility and capacity to act into account in achieving an equitable apportionment of shares of emissions to be cut back, and 4) taking the negotiation back to the full suite of UNCCD member countries only after these 13 have reached agreement.  It’s an interesting proposal, although one would still need to get the US, China, Russia, India, and so on to reach agreement, and then gang up and push Canada and Australia to agreement also.

There were several interesting details in this article concerning Canada.  Canada ranks 7th in this group of 13 in terms of cumulative emissions, with 2.1% of total world emissions since 1990.  One can say that Canada only contributes a measly 2%, or note we are the 7th worst carbon polluter.  I expect Stephen Harper to cling to the former view.  Secondly, Canada’s production-based emissions since 1990 are almost identical to its consumption-based emissions: 10,693 metric tonnes CO2 produced in fuel and other products, and 10,953 metric tonnes CO2 released during consumption.

So much for the Harper government line that our CO2 performance looks so poor relative to other countries because we are a resource-exporting nation.  No, we export a lot of fuel that then gets burned elsewhere, but we also emit a lot of CO2 in operating our economy – about 260 metric tonnes more.  We are just really rather irresponsible emitters of CO2 all around! 

Some other countries have substantial imbalances, notably South Africa (29%), Russia (26%), and China (15%) which produce a good deal more CO2 polluting products than they consume, and the EU (22%), and Japan (21%) which consume more such products than they produce.

The compromise sounds to me like a worthwhile approach to explore.  But of course, I thought having the full 100+ countries sit round the table and agree would be an approach that would work once everyone understood how serious the problem is.  I keep forgetting that politicians only think short-term, and only about winning.

Growing Recognition of the Value in Formal Economic Accounting of Natural Capital

In the same issue of Nature Climate Change, Matthew Agarwala, of the London School of Economics, and three colleagues provide a commentary on economic accounting for natural capital.  They begin with the point that at least $ 40 Trillion per year is omitted from estimates of the global annual GDP.  This $ 40 Trillion is an estimate by the World Bank of the value of goods and services derived from the natural world for free every year.  It’s an under-estimate because the World Bank only used data from some of the ecosystem goods and services in just 100 countries.

Before going further, many ecologists, including me, have a real concern that converting nature to a sum of money representing what it does for us risks turning nature into a commodity that might be replaced by something man-made and believed to do the same things.  In fact, nature has tremendous esthetic, spiritual, cultural, historical and religious value beyond its value in providing us with goods and services.  Also, nature does not exist to fuel our economy, and we are hubristic enough without encouraging each other to convert nature into dollars and cents.  Still, for those, like Henry Paulson who live and breathe dollars and cents, pointing out the tremendous economic value provided to our economy by nature is probably a worthwhile exercise.  Just remember that is not the only value nature possesses.

Anyway, Agarwala and colleagues maintain that both governments and corporations are beginning to see the value in providing a proper economic valuation of their natural capital, in order to more accurately measure their economic performance, assets and liabilities.  They tell of a recent demand by shareholders that giant ExxonMobile “disclose the potential impact on natural capital asset (fossil fuel reserves) values if governments were to enforce emissions restrictions consistent with the 2 °C temperature rise target.”  Shareholders have a right to this information because the reserves are the major capital asset of the corporation, and if they suddenly become reserves that cannot be marketed, the value of the corporation drops like a stone.  The resulting report, which ExxonMobile has to be forced to publish, claimed that “none of [ExxonMobil’s] hydrocarbon reserves are now or will become stranded” on the grounds that they consider such an aggressive emissions reduction policy to be “highly unlikely”.  Now doubt they consider it highly unlikely because they believe they have the governments of the world suitably stuffed into their corporate back pockets (and evidence from Canada suggests they may well be right).  In fact, it is almost certain that there will be substantial ‘stranded assets’ left in the ground when we finally come to our collective senses and stop using fossil fuels.  If that does not happen, we will be so busy dealing with run-away climate change that we won’t much care about balance sheets or profits and losses in the markets.

Agarwala and colleagues discuss the difficulty of adequately valuing many natural capital assets – what is the value of replenishing oxygen in our atmosphere?  Plants on land and in the oceans share this immense job, while we keep consuming it.  They suggest that building economically acceptable approaches to value carbon, or CO2, may be a good beginning even though it is more of a liability than an asset, with other types of natural capital valued later.  They also consider the ways in which climate change and economic activity interact in affecting value of natural capital, and how it is important to include all important types of natural capital in the accounting.  For example, they state “hydropower in the Mekong River Basin (MRB) may serve a low carbon agenda, but the MRB is also a biodiversity hotspot, home to at least 877 fish species, the world’s largest inland fishery and the 70 million people that depend on it for up to 70% of their protein intake.  The more than 60 dams currently under consideration on the Mekong would interrupt nutrient deposition and fish migrations, compromising downstream agriculture and fisheries with estimated impacts ranging from +US$33 billion to –US$274 billion.  A focus purely on carbon would omit these broader natural capital impacts with severe consequences for public wellbeing, private sector revenues and social and political stability.  Crucially, the economic valuation of natural capital offers a common metric, allowing these competing goals and impacts to be compared on local and global levels”.

Of course the real value of natural capital accounting comes when decisions are being made on the profitability of undertaking particular ventures, whether these are being contemplated by governments or corporations.  If those planning a venture were required to not undertake it unless there is an overall economic profit in so doing, or if the overall economic loss is offset by the resulting societal benefit, we would be making far better decisions, as governments or as corporations than we do now.  It still won’t turn governments or corporations into model conservationists, but I think it would move them a lot closer to this goal than going on as we presently do.

Why, just today, Twitter alerted me to an article describing a hare-brained scheme by some group of Italian developers fronted by John Travolta (who just lost any cred he ever had with me) to turn Lighthouse Reef, one of Belize’s three Caribbean atolls, and location of two UNESCO World Heritage sites, into a megaresort for millionaires, called Puerto Azul, including a private jetport, a Formula One speedway, and an outdoor amphitheatre dedicated to Andrea Bocelli.  On a coral reef!  It seems some money has already been used to fly Belizean dignitaries to a glitzy launch event in Cannes, but it is not a done deal, and I’d like to believe Belize is capable of avoiding such a travesty.  (I do not need natural capital accounting to know this is a terrible project, but if the accounting was done it might help to persuade those who apparently do not see anything wrong with building a Formula One speedway on top of a reef.)  The fact that such outlandish projects proceed to the point of a launch party is bizarre.  There is a fairly extensive desert just across the Mediterranean, south of Italy with lots of room for speedways and amphitheatres.  You don’t build them on top of living reefs.  You really don’t.  It’s simply the wrong thing to do………


The Blue Hole on Lighthouse Reef, perhaps soon to be a new Formula One speedway, a giant amphitheatre, and a modern jetport.  Some people (like John Travolta) just seem to like to mess things up!

But come to think of it, the world does include Dubai, which has done a masterful job of building stuff on top of its few scattered, suffering reefs.  So let’s use natural capital accounting to try and hold brain-dead developers and their glitterati friends to a higher standard than is currently used!


The Dubai coastline, sort of a developer’s wet dream.  Fortunately, the 2008 global economic crash has ensured that most of this awfulness has not yet been built.  Palm Jumeirah, the structure at the left, was built, and now functions as a rather strange holiday destination.  Image from Wikipedia

Categories: Climate change, Economics, Politics | Leave a comment