Archive for November 3rd, 2011

It never ceases to amaze me which species get picked for special attention. The reasons are easy enough to understand; either they are magnificent, attractive, cuddly, intelligent, or perhaps have some form of cultural significance as a national symbol. The giant Panda and Polar Bear are classic examples of this phenomenon of bias towards saving species that seem ready-made for conservation campaigns on account of their being so photogenic.

In these two cases, however, it is hardly surprising that they have become endangered; both are bears and bears are essentially omnivorous opportunists, yet these particular bears have taken a dangerously narrow evolutionary path into high-risk specialisation. Their sacrifice of flexibility has made them vulnerable. Perhaps, in the end, it’s really just too bad. Enjoy it while you can, adapt or die, has always been the Earth’s motto.

Of course, with the exception of occasional freak events causing rapid transformation of climactic conditions and immediate destruction of habitat – an asteroid impact, snowball Earth, or large-scale volcanic upheaval – most species have had plenty of time to adapt to changing conditions, and those who could not adapt lie frozen in stone; the dead ends of evolution; the leafless twigs that fell from the tree.

The wild populations of giant Panda might be at serious risk from habitat loss, and indeed, a great deal of bamboo forest remains threatened by development, but the campaign to save them has become almost embarrassingly successful, so far as captive breeding programs are concerned. They are not hunted and harvested for food, at least not on an industrial scale, and as a potent national symbol of China and, indeed, as an accepted symbol of international efforts to save species and habitat, they are at relatively little risk of going extinct either in the wild or in captivity.

Sadly, the same cannot be said of Polar Bears, whose habitat is shrinking rapidly and whose lifestyle is not readily adaptable to different conditions. Given more time, they would likely adapt or evolve, though there is no guarantee of that. With the retreat of the last ice-age, the woolly mammoth was driven further and further north, until the last populations were restricted to arctic islands in northern Russia where their isolation led to that common evolutionary phenomenon of dwarfism – they shed most of their bulk and shrank to the size of hippos. Polar bears, one suspects, will not have time on their side, yet in all likelihood, if given sufficient territory and left unmolested, small populations will cling on in far northern Canada or Alaska. They may shrink and be forced to significantly adjust their hunting range and habits, but they seem sufficiently clever and resourceful to pull through.

Other species will not be so fortunate, even when their plight garners public attention and attracts conservation dollars. Pity the northern white rhino, a magnificent odd-toed ungulate. There are now five males and two females left on the planet. That number again: five males and two females ON EARTH, all in captivity. It’s enough to make you cry. Pity the primates. More than half of the Earth’s primate species are threatened with extinction. However much we love them, however good they look on posters, television advertisements and campaign leaflets, their vulnerability to the consequences of war, poverty, hunger and greed is all too real. If peace and prosperity came to the jungles of Congo, things might pan out a lot better for the Gorilla and chimpanzee, but as things stand, their situation is extremely tenuous.

As one reader joked in a letter to the New Scientist, the best way for creatures to ensure survival is to evolve as rapidly as possible into a more lovable, cuddly form; big eyes and soft fur can do wonders for a species on the conservation wheel of fortune. Yet, if we can’t even manage to save the cuddly ones, then what hope is there for all the frog, flower, amphibian, bush, beetle, tree, fish and reptile species, many of which have gone extinct in recent times due to habitat destruction and climate change?

There are many and varied estimates of the background extinction rates, and indeed, similarly varied estimates as to how many species there actually are on the planet. Judging from the fossil record, the background extinction rate is estimated to be roughly one species per million every year. Very rough estimates suggest a current total of around ten million different species on the planet, and a current extinction rate of somewhere between 27000 and 30000 plant and animal species per year. Just as geologists have recently agreed that human warming of the planet justifies acknowledging the end of the geologically short and wonderfully mild Holocene epoch, and the commencement, beginning with the industrial revolution, of the Anthropocene, so biologists, among others, agree that we are now in the midst of a mass extinction, the likes of which have occurred several times already in Earth’s history, though not, so far as we are aware, through the agency of one dominant species. Though, having said that, we cannot ignore the climatic impact of, for example, oxygen-producing cyanobacteria, who for millions of years, beginning somewhere between 3.4 and 2.7 billion years ago, exhaled this waste-product on such a scale that the planet could no longer absorb it, until, roughly 2.4 billion years ago, the Great Oxygenation Event occurred, wiping out much of the planet’s anaerobic inhabitants and ultimately triggering the first and longest snowball Earth event.

Still, just because we are in good company does not make being responsible for the sixth great extinction in the planet’s history something to be proud of. As things stand, an estimated fifth of the world’s mammals, a third of its amphibians, more than 25% of its reptiles and up to 70% of its plants face the threat of extinction. That is, to say the least, seriously fucked up, and the only way to arrest the situation is to, quite literally, stop doing everything, switch off the nuclear power stations, disarm the warheads, sit down wherever you are, and quietly die.

More realistic, of course, is the promotion of peace, sustainable development, recycling and efficiency and the end of overconsumption. Yet, sadly, despite the world having become considerably more peaceful on the grand timescale, prosperity is growing at such a pace, irrespective of hiccups, financial crises and what have you, that consumption and atmospheric pollution are increasing very rapidly indeed. With the exception of the species we farm and harvest, and those who are well adapted to our artificial environments, such as rats, cats, dogs, pigeons, squirrels, possums etc, almost everything is under threat, and in recent years, I have become seriously alarmed by the plight of the Tuna.

The tuna is a truly magnificent creature, of which there are over fifty different varieties. The Atlantic Bluefin tuna can grow to a size of four and a half metres long, can weigh as much as 650kg, and can swim at speeds of up to 70kph. Tuna do not have white flesh like most fish, but their muscle tissue ranges from pink to dark red. This coloration derives from myoglobin, an oxygen-binding molecule, which tuna produce in significantly higher quantities than most other fish. Some of the larger tuna species, such as bluefin tuna, have warm-blooded adaptations, and can raise their body temperature above water temperature, thus enabling them to survive in cooler waters and to exploit and inhabit a far wider range of ocean environments.

Tuna not only look magnificent, but they are magnificent. The sad reality, however, is that tuna, the world over, are on the brink of a terrible catastrophe. As Greenpeace’s 2008 report entitled Tinned Tuna’s Hidden Catch states:

“Of the 23 commercially exploited tuna stocks identified: At least nine are classified as fully fished, a further four are classified as overexploited or depleted, three are classified as critically endangered, three are endangered and three are classified as vulnerable to extinction.”

Worldwide, Greenpeace estimates that 90% of large predatory fish have already been wiped out. Catches are down dramatically in all fisheries. In the Mediterranean, the World Wildlife Fund has estimated that tuna stocks will reach complete collapse as early as 2012. In 2007 the breeding population of tuna was only a quarter that of fifty years ago and the size and weight of mature tuna has more than halved since the early 1990s. Attempts by scientists, marine biologists and fisheries experts to dramatically reduce quotas have brought only tokenistic, inadequate responses and led to an explosion of illegal fishing that goes largely unpoliced.

It’s not merely the scale of the industry causing problems, but also the fishing techniques used. The common use of Fish Aggregation Devices (FADs), wherein fish are lured to a particular zone and then scooped up en masse, not only results in the catching of juvenile tuna, but also lures many other species, juvenile or otherwise, which make up an estimate ten percent of the catch. Not only do FADs act as death-traps for young tuna, but they draw tuna away from migratory routes, resulting in loss of optimal feeding opportunities, seriously effecting the life-cycle of tuna which are not caught, and thus having broader impacts on the entire marine ecosystem. Similarly, long-line fishing, where lines of up to 100km are used, are also responsible for significant bycatch.

Big Tuna likes to make a special point of their tuna being “dolphin friendly.” Yet, as Greenpeace states:

“Many fishing practices that are labelled dolphin friendly still result in the catch of a host of non-target species, known as bycatch, including turtles, sharks, rays, juvenile tuna and a huge range of other marine life.”

Some companies have gone a step further and changed their practices. Around the corner from my house is a huge billboard advertising the environmental credentials of Greenseas tinned Tuna. There are, in fact, two advertisements side by side, each with the large happy face of a marine species, pleased to have avoided being caught unnecessarily. Greenseas can claim some credibility on this front, as they have made the important commitment to stop buying tuna caught using FADs. Yet, when we consider the rate at which the tuna themselves are being exterminated, this feels like a diversion; more of the green-washing bullshit we’ve come to expect from big business in the last decades.

The simple fact is that Big Tuna may claim to be dolphin friendly. They may claim to be dugong friendly. They may claim to be turtle friendly, but they are definitely not Tuna friendly. The Tuna, in all its glorious varieties, is, quite literally, being fished to death. In the vastness of the oceans, it would be difficult to hunt down and kill every single tuna available, it would be a hell of a job to drive them to extinction, yet humans are currently giving it their absolute best shot.

The rising popularity of sushi, along with tuna’s longstanding popularity in salads, pasta dishes and all manner of culinary creations, has dramatically increased the scale of the market in recent years. This commercial success guarantees that the industry will pursue tuna for as long as possible, and there seems relatively little effort within the industry itself to harvest tuna in a sustainable fashion. Governments must co-operate internationally to put a stop to current quotas and practices, and actively police illegal fishing.

Greenpeace advises that in order to save tuna populations the world over, the fishing industry must stop using FADs and switch to line and pole fishing, which are highly targeted towards adult tuna; governments must impose and enforce marine reserves to safeguard ecosystems from destructive fishing practices; supermarkets should stop buying tuna products caught using FADs, only support sustainably caught tuna, and help to promote the creation of and awareness about marine reserves.

The issue of bycatch is bad enough, but the scale of tuna fishing must be severely restricted in order to avoid a potential environmental disaster. We cannot even begin to imagine the devastating impact on an ecosystem of removing 90% of its predatory species, but the resulting imbalances are bound to be hugely disruptive.

Sure, it sucks not being able to eat tuna, because I admit, like so many people, I have always enjoyed the taste of it. Yet, for the last three or four years, I have not been able to buy it out of a colossal sense of guilt. I recently swore off eating cephalopods (squids, octopi) after reading a New Scientist feature on their extraordinary intelligence. When, two weeks ago, I broke my pact and ate squid, then, the following day, found myself with food poisoning, I felt a rare case of instant karma. At least I learned my lesson, and I won’t be eating those guys again.

Of course, as someone who eats dairy, I leave myself open to accusations of hypocrisy, for the dairy industry is not an industry known for its sustainability. Of course, it’s not the cows that are threatened – though they are often mistreated – but the environment, on account of industrial scale farming practices.

It would be nice to think that humans will wise up to their destructive habits and avert a major catastrophe, both on land and at sea, but I’m not especially confident. Either way, don’t be surprised if the price of tuna skyrockets in coming years. Some time soon, this already critical situation is going to hit the wall.

ps. apologies for lazy referencing. After doing a PhD, I never want to footnote again…

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