Antarctic Krill – Small crustaceans powering giants

Living in the Southern Ocean, these small crustaceans generate an enormous biomass that sustains a wealth of antarctic fauna, as well as human economic activities

Imagine …

… an ocean with a low temperature of -2 0C, and a high temperature of 10 0C. Imagine further frequent storms because of the contrasting temperatures between sea ice and open ocean, and open seas without a human soul for miles around. This is the Southern Ocean, that encircles the continent Antarctica.
Ocean boundaries are of course arbitrary, and the very existence of the Southern Ocean is not necessarily agreed upon by everyone. As the Wikipedia entry on the Southern Ocean notes:

The International Hydrographic Organization (IHO) has not yet formally published its 2000 draft definition of the existence of the ocean and of it being south of 60°S due to global ‘areas of concern’ such as the Sea of Japan.

Pending the IHO’s official description, this post is about a species that calls the Southern Ocean its home and which is single handedly responsible for feeding many impressive mammal and bird species: whales, seals, squids.

Antarctic krill

That species is Antarctic Krill or Euphausia superba. It is in fact one of 89 species of krill, which is subdivided over two families, the Bentheuphasiidae and the Euphausiidae. The latter family consists of crustaceans that look like shrimps. Krill as a group is widespread, occurring in many open seas, including the Pacific Ocean, the Indian Ocean and the Gulf of Oman. But this one species, E. superba, is the most abundant, living in large schools or swarms in the Antarctic waters between the continent and the polar front, generally within depths of 100m or less. It is estimated to reach a biomass of 500 million tonnes and in that respect thought to be the most abundant animal species on the planet.

Close-up of krill

What a biomass of 500 million tonnes can do

Details on the life of krill or more specifically E. superba, can be found on many places on the Internet, such as here, here, or here. In this post I want to highlight the ecological role of krill, and specifically that of E. superba. Krill are not the lowest level of the food chain, but one step above it. They feed on phytoplankton — floating, mostly single cell plants. The many species of phytoplankton are the primary producers, capturing sunlight and converting it into energy. Surprisingly, the next step after Antarctic krill can be huge mammals, baleen whales, including the Blue Whale, Balaenoptera musculus, the largest animal currently existing on the planet. The Blue Whale does not live from E. superba alone. Among the other krill species it eats are Euphausia crystallorophias, E. pacifica, E. valentini, Meganyctiphanes norvegica, Nematoscelis megalops, Nyctiphanes australis, N. simplex, Thysanoessa inermis, T. longicaudata, T. longipes, T. raschii, and T. spinifera.

From tiny algae to massive whales in three steps

Krill dependencies

This seems a simple enough food chain. In three steps from tiny sunlight absorbing plants to the largest animal on the planet. Although that in itself is amazing enough, food relations are rarely that simple. For one, the Blue Whale itself — although largely dependent on krill — eats different species depending on where it is, in the Southern Ocean, or the Pacific, or elsewhere. And then, other species eat E. superba as well, and are themselves eaten in turn. Food chains form food webs.

A simplified food web based on E. superba. Adapted from Discovering Antarctica. This food web can be made more complex by adding many more species. There are for instance a number of squid species, more than one species of Albatross, more predators can be added, and so on
 

Three things become clear from the simplified food web:

  • Phytoplankton is the basis of (almost) all life in the oceans. If the phytoplankton would decline, so would most other life as a consequence. (Exceptions are organisms such as for instance bacteria living at deep-sea hydrothermal vents, which find an alternative source of energy in those vents.)
  • E. superba sustains quite a number of animal species directly through it’s massive numbers.
  • A number of animal species depend on E. superba indirectly, forming intricate food webs.

Fisheries

We as a species belong mainly to the last group, and it happens in two ways. The first way is we fish krill directly using most of it as fodder. The fodder sustains aquaculture and other industries, which feed us. (A small portion of the krill we catch is used for direct consumption and that is why we also belong a little to the group of animals that rely on E. superba (and other krill) directly.) The second way is we catch fish that feed on krill.

The krill fishery has a global harvest of 150-200,000 tonnes per year. That is mostly Antarctic krill and North Pacific krill (E. pacifica). The catch of Antarctic krill amounts since the mid-1990s to about 100-120,000 tonnes per year. This is far below what the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR) allows: nearly five million tonnes per year. These CCAMLR quota are criticised as being too high, because there are no precise estimates of krill biomass, and because krill is declining since the 1990s.

Fish catches are much more modest, at least at the end of the previous century. The Wikipedia entry on the Southern Ocean refers to fisheries on krill and fish amounting to almost 120,000 tonnes between mid 1998 and mid 1999. Of this, 85% was krill, and 14% was the Patagonian Toothfish Dissostichus eleginoides. Both krill and Patagonian Toothfish are subject to regulated fisheries, where operators follow CCAMLR regulations and conservation measures, and unregulated ones.

Euphausia superba and us

From the above, it follows then that this small crustacean is of great importance. The significance this one species has for our existence is aesthetic and spiritual, economic, and survival.

The aesthetic and spiritual (in the sense of taking joy or pleasure from being in nature and experiencing it) significance is by far not negligible. Maybe it’s not krill itself that evokes this, but surely many of the species that rely on it do. Just imagine what the world would be without squid, or perhaps the more impressive Blue Whale or Wandering Albatross, or the more endearing Crabeater Seal (especially its cute pups!).

Economically E. superba is of considerable importance. A fisheries catch of 120,000 tonnes per year may perhaps not be much when compared to overall fisheries globally, but they are not small numbers either. A good many people and companies rely on these fisheries, aside from the food it provides.

It would also seem that krill lets us survive. Food webs are complicated processes, and a good many species — more than the simplified food web above depicts — are part of this food web. The illustration shows clearly that E. superba has an oversized role in driving the ecosystem processes in the Antarctic. The Antarctic is not isolated. Sea boundaries are not fixed, firm lines. The various systems and processes of the Southern Ocean interact with other processes, food chains and food webs in other regions of the ocean. Should the krill population decline dramatically, and thus the many species that rely on it, then this will have a ripple effect, the outcome of which is uncertain.

The outlook for E. superba

Unfortunately, the outlook is not too good. Krill populations have been declining since the 1970s. The reasons for that are not understood. But the decline is still ongoing, and is now exacerbated by other factors.

One such factor is overfishing. Krill Facts writes that until 2009 the harvest was stabilised around 120,000 tonnes per year. But since then it has been increasing to more than 200,000 tonnes. Overfishing is a real threat, illustrated by the example of the Mackerel Icefish, Champsocephalus gunnari, which used to be the most common fish in coastal waters in the Southern Ocean, but no longer so due to overfishing in the 1970s and 1980s. The quoted numbers of krill biomass sound impressive, but since so many animals depend on it, overfishing by humans can have great impacts on a system where Antarctic krill is the cornerstone of the system.

Another factor is increased ultraviolet radiation as a result from the ozone hole in the Antarctic and which has been reported as having caused a reduction of 15% in marine primary production. That means considerable lower amounts of phytoplankton on which krill depends to produce that amazing biomass.

And then there is climate change. The oceans have been growing warmer which will affect species when the limits of their temperature ranges are surpassed. Sea water is also becoming increasingly acidified due to an increase of absorbed CO2. The increase in acidity affects the production of phytoplankton negatively, the very basis of the system.

Because of these and other factors krill numbers are declining. Figures I have found include a recently updated entry in Wikipedia on krill fisheries which gives an actualised estimate of 379 million tonnes of krill, which would mean a decline of more than 120 million tonnes or 24% of the estimate of 500 million tonnes quoted at the beginning of this post. In addition, Cool Antarctica writes

Krill numbers may have dropped by as much as 80% since the 1970s – so today’s stocks are a mere 1/5th of what they were only 30 years ago.

Should we worry ?

Yes, we should.

The hole in the ozone layer appears to be on the mend; overfishing can be regulated, and the CCAMLR appears to have a positive effect; global warming however, is ongoing.

At the time of writing this post, news outlets reported on the agreement between USA and China on addressing emissions causing climate change. The reactions on the news vary quite a bit, but with many reporting that environmental organisations broadly welcomed the deal. Friends of the Earth however writes:

While the U.S.-China Announcement on climate change creates important political momentum internationally, it falls significantly short of the aggressive reductions needed to prevent climate disruption.

Although the rest of the article uses strong language, this formulation of “preventing climate disruption” is still an understatement. Climate change is already happening, and therefore the climate is already disrupted. What’s more, unless CO2 will be taken out of the sky, conditions will be changing or at least be different from current ones, for centuries to come. And aside from temperature changes — which fuel extreme weather events with potential disastrous consequences, sea level rises, and, for instance, declines in agricultural production — there is acidification of the oceans that already causes phytoplankton and carbonate dependent organisms such as corals to decline. This will in turn will have great disastrous effects on fisheries worldwide, and E. superba in particular. And as a consequence, whales, seals, fish, squids will find less and less food. It remains to be seen whether one or more other organisms can take its place to sustain the food web.

It’s not possible anymore to stop climate change. We can only work to limiting climate change and mitigate it’s effects.

SOURCES

To avoid repeating links and references, here is a list of the principal sources I have gleaned information from for this post:

Encyclopedia of Life: http://eolspecies.lifedesks.org/pages/17370

Antarctic and Southern Ocean Coalition: http://www.asoc.org

The Species 2000 & ITIS Catalogue of Life: http://www.catalogueoflife.org/col/details/species/id/1447042

Website on Antarctica maintained by Paul Ward: http://www.coolantarctica.com

Discovering Antarctica, a website operated by the Royal Geographic Society: http://www.discoveringantarctica.org.uk

Friends of the Earth: http://www.foe.org

Krill Facts website maintained by the International Science and Health Foundation: http://www.krillfacts.org

MarineBio Conservation Society: http://www.marinebio.org From Wikipedia: http://en.wikipedia.org/wiki/Ad%C3%A9lie_penguin http://en.wikipedia.org/wiki/Antarctic_krill http://en.wikipedia.org/wiki/Antarctic_toothfish http://en.wikipedia.org/wiki/Blue_whale http://en.wikipedia.org/wiki/Emperor_penguin http://en.wikipedia.org/wiki/Krill http://en.wikipedia.org/wiki/Krill_fishery http://en.wikipedia.org/wiki/Mackerel_icefish http://en.wikipedia.org/wiki/Ocean_fisheries http://en.wikipedia.org/wiki/Patagonian_toothfish http://en.wikipedia.org/wiki/Phytoplankton http://en.wikipedia.org/wiki/Southern_Ocean

Edited to adjust last sentence above the list of sources (10 December 2014)

The Power of Sea-Monkeys – How tiny invertebrates probably impact the global climate

Feature image credits: This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license. Attribution: © Hans Hillewaert. (https://en.wikipedia.org/wiki/Brine_shrimp#/media/File:Artemia_salina_4.jpg)

Small sea-dwelling organisms impact human life through commerce and probably also through ocean currents, and, ultimately, the climate

Sea-Monkeys – Do these really exist ? Yes, they do thanks to a Mr. Harold van Braunhut, except that they are not monkeys. He popularised the use of brine-shrimps as part of a water purifier. He did this in 1957, and gave the name Sea-Monkey to brine-shrimps in 1962. (Read all about it here.) They are also known as Aqua Dragons. Brine-shrimps or branchiae-legged crayfish (=crayfish with gills on their legs), refer to species of the genus Artemia. Artemia spp. belong to the phylum Arthropoda, the class Branchiopoda, the order Anostraca, and the family Artemiidae.

As a group, Artemia spp. occur in most of the world: Africa, Asia, Europe, Latin America, and Australia. It’s an old group, evolutionary speaking, having lived together with dinosaurs 100 million years ago. A. spp. are tiny, about 10 mm long, some up to 20 mm. Their biology is interesting. One species, A. parthenogenetica, can reproduce without males present. Eggs can survive for years in a dried state to hatch later, a phenomenon known as cryptobiosis.

The commerce of Sea-Monkeys

However, this blog is not about details of the biology of such species, however interesting. If you’re interested in that there is plenty of information on the internet, for example the page on A. salina in Wikipedia, or the one on Sea-Monkeys. There is also a website dedicated to Artemia: Artemia World (a company dealing in Artemia products).

This blog is about the importance of biodiversity, more specifically, for the well being, if not survival, of us, human beings, directly or indirectly. So how do we relate to these small crayfish?

Past delicacy

According to Artemia World, brine-shrimps were in the past used as food by a/o American Indians (notably in Utah, where they were found in Utah’s Salt Lake), and Arabs, who made a paste out of brine-shrimps caught in the Nile, this being known in both cases as delicious food.

Nowadays Artemia is exclusively used as fish fodder. In the more recent past, this was mainly for aquarium enthusiasts. According to Artemia World, A. spp. are good as aquarium fodder during all three phases of their life cycles, as eggs, as larvae (the so-called Nauplius larva), and as adult. The phenomenon of cryptobiosis makes storage of Artemia-based fodder very convenient. Eggs (or cysts) can be stored long term if kept dry, and still provide living fodder later.

Where Artemia really has an impact though is in aquaculture. It is used on an industrial scale to feed prawns, crabs, hermits and lobsters. Artemia World also writes that a boom in the 1970s of marine culture of “evrigalin” salt-water fish in the mediterranean was based on A. spp. (But I could not find what “evrigalin” refers to. If anybody knows? ….) There are a number of websites of companies that sell Artemia products and give details on nutrition value and the like (including Artemia World).

  • Life cycle of Artemia salina
  • Life cycle of Artemia franciscana
  • Artemia salina
  • Artemia cysts and nauplii larvae
  • Hatching Artemia egg
  • Artemia nauplii larvae
  • Close-up of Artemia nauplius larva
  • Asian Sea-bass feeding on Artemia larvae
  • Hatched Artemia cyst with empty cyst shell
  • Artemia culture in a pond in Thailand
  • Artemia breeding ponds in San Francisco Bay, USA
  • Artemia cysts and hatchery feeds
  • Fluid aquarium feeds based on Artemia products
  • Filter nets at sluice gates

Artemia and conservation

Based on Artemia World’s information, the use of Artemia as fish fodder also impacts on conservation: (young) sturgeons who no longer live in conditions that allow reproduction and living due to hydropower plants and other artificial dams, can be fed Artemia in special pools. When they are strong enough, the young sturgeons can be released in their natural environment.

In addition, Artemia is used as a species to test the toxicity of chemicals. However, according to Wikepedia, it has gained that use despite the fact that it is a very resilient species, and is therefore not a sensitive indicator species.

Brine-shrimps or Sea-Monkeys then, have quite an impact on human life and economy, and also play a role in conservation and environmental control and monitoring.

Artemia salina – To be or not to be

Sea-Monkeys may exist, but the situation concerning the existence of Artemia salina is somewhat confusing, and to what precisely Sea-Monkeys refer is not clear either. A. salina as a species can be readily found in the online and continuously updated Catalogue of Life, and the data portal Global Biodiversity Information Facility. Yet, Artemia World says that A. salina has been declared extinct and that now only seven other species of Artemia exist (A. tunisiana, A. species, A. franciscans, A. parthenogenetica, A. sinica, A. persimilis, and A. urmiana). It’s a bit strange, especially with the additional information that of the seven species that now exist one would be called A. species! This is probably because of a map that lists A. sp. In Kazakhstan:

Distribution map (found at www.aquaculture.ugent.be)

The Catalogue of Life lists in addition to the species listed by Artemia World A. monica, A. gracilis, and A. tibetiana, and also lists A. salina (sic!). The Catalogue of Life is continuously updated, so it’s probably better to follow the listings there. Artemia World also writes that Sea-Monkey is a name given to a large-size “commercial” form of Artemia, also referred to as Artemia NYOS, developed by the no longer existing New York Ocean Science laboratory, and which is not accepted as a separate taxon.

The naming conundrum

Ocean currents

This discussion on whether A. salina does or does not exist, of to what Sea-Monkeys precisely refer to, is relevant to the extent that this humble but useful crayfish has recently been studied to understand better an other phenomena that affect humans (and other organisms) worldwide: ocean currents. The fact that it has been studied, would imply that the species is not extinct. This contradictory state of information may be the result of recent reclassifications perhaps, but, if so, I did not get that information from the Catalogue of Life.

A. salina itself does not live in the sea. It lives in inland salt water bodies (another element that makes the term Sea-Monkey for this species confusing, as it normally does not live in the sea!). A. salina has been studied as a proxy for numerous other small sea-dwelling organisms, including other Artemia species and a/o krill. Monica M. Wilhelmus and John O. Darbin of the California Institute of Technology, USA, studied the movements of A. salina in water tanks. Sea-monkeys make daily movements, as lots of other small organisms in the sea do. During the night they are closer to the surface than during the day. The two researchers studied the upward migrations using high-speed cameras and microscopic silver-coated glass spheres. Popular Science which discusses this research posted also a video where you can see the movement and the effects it has on the water column. Whereas each shrimp has only a tiny effect on the water, the combined effects of large numbers of crayfish swimming upwards, has a measurable effect on the water column: they generate a current that is stronger than the sum of those created by each individual. The researchers think that the collective action can be powerful enough to influence broad circulation patterns. In the words of Popular Science:

… if other small sea creatures influence water flow in similar ways, it could mean that together they add a trillion watts of power to the ocean’s currents. That means that even the most minuscule organisms could drive the distribution of salt, nutrients and heat throughout the oceans, and they may even influence climate.

In the words of the original article:

(…) We hypothesize that the evolution of Kelvin-Helmholtz instabilities at the boundaries of the intermittent jets within a DVM could trigger Rayleigh-Taylor instabilities across surfaces of constant density and the formation of internal waves along those surfaces. Both processes could potentially result in large mixing eddies, which may explain previous findings of density overturns after krill migration in the ocean. (…)

Ecological processes and climate

Biodiversity manifests itself in a myriad lifeforms, which exist in a myriad of different ways. Whereas through ecological studies we know and think to understand many systems, research like this shows that we still do not know everything, and do not yet understand the many different systems and how they different species interact with each other and with the inanimate landscape elements. Tinkering with systems you do not completely know and understand can be hazardous. We are now entering a phase in Earth’s existence where we tinker with one of the most basic of systems that determine how we live, the climate. As the research above shows, we still do not completely understand the complex systems that determine our climate, and probably never will completely understand such systems. Tinkering with the climate looks more and more a hazardous game.

Perhaps though there is still hope: Artemia made it to the cartoon world, and has become a hero !

What does Galileo have to do with Climate Change ?

THIS POST IS AGAIN ON CLIMATE CHANGE, RATHER THAN ON BIODIVERSITY. THE REASON IS THE LINK MADE BETWEEN CLIMATE CHANGE AND GALILEO IN A RECENT DISCUSSION THAT I CAME ACROSS

Recently I came across a discussion on the site Climate Science Watch. This discussion was triggered by an OpEd in the Wall Street Journal by Mr. Steven E. Koonin, titled Climate Science Is Not Settled. In it, Mr. Koonin argues on basis of a number of arguments that far from being settled, the climate science is not complete enough to direct climate policy. Climate Science Watch, which describes itself as:

Climate Science Watch is a nonprofit public interest education and advocacy project dedicated to holding public officials accountable for using climate research effectively and with integrity in dealing with the challenge of global climate disruption.

I picked up on it, and criticised this OpEd on a number of points, chief among them inaccuracies and fallacies. It argued against the concluding idea of the article, that action should be delayed and more climate research be done.

Mr. Koonins view

Climate Science Watch is an open site where everyone can contribute (if the moderator accepts the comment). A number of people contributed. One of the comments referred to the consensus among (climate) scientists with regard to the conclusions of the Intergovernmental Panel on Climate Change (IPCC) and found such consensus not correct. The argument went like this:

And, that is the problem – that you believe that science is based on “the views shared by leading climate science experts.” That approach is wrong. Always. No one, scientist or not, should ever view science as a matter of counting the leading experts. That approach is wrong. Always. No one, scientist or not, should ever view science as a matter of counting the leading experts. The Nazis once published a book with numerous German scientists “refuting” Einstein. Einstein replied that if they had had a legitimate point, one would have been enough. Einstein was right. Science is not settled by counting noses. It is settled by evidence. To “pay attention to the views shared by leading… science experts” would mean the death of science. Or to quote Galileo, “’In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.” That is science, not counting noses.

Wrong argument

I have always felt something wrong with that argument and started to reason it out. I posted the following comment:

Thanks to Zite, an iPad app, I came across this discussion started on basis of the OpEd of Mr. Koonin. The discussion touched upon the conundrum of the consensus among scientists on the various issues surrounding climate change. The argument against it is that science is not done by counting noses, but is based on evidence. Hence, those that argue against the current stark warnings of climate change – ranging from talking down the risks to flat out denial – refer also in this discussion, as has been done elsewhere, to Galileo, and in this case also to Einstein. It’s not consensus they say that should direct policy, but evidence. Galileo and Einstein are the heroes, because they based themselves on evidence against mainstream opinion and convictions. I can add another scientist to this illustrious group. Charles Darwin, just ahead of Alfred Russell Wallace, published his studies and findings on evolution. He kept to it, despite the ridicule he and the theory of evolution had to endure.

To me, using this argument in the debate on climate change is a red herring. As far as I’m aware, the discussions and conclusions, with identification of uncertainties and risks, is all within scientific debate. The scientists supporting the IPCC conclusions, do that on basis of the evidence, discussed, perused, debated and evaluated.

This is different from the situation that Galileo found himself in, or, for that matter, Darwin. Theories, evidence based, were not accepted by groups who did not advance scientific arguments. Certainly the christian church which denounced Galileo did not do that. While Darwin’s theories were scientifically debated, society was not prepared to just accept it on basis of non-scientific arguments, fed again, mainly, by religious arguments. Galileo’s theories were over time accepted based on ongoing scientific observations, debate and advancements. Similarly, evolutionary theory was accepted over time as the scientific arguments of the day against it did not hold up in view of the evidence produced. The arguments nowadays levelled against evolution are non-scientific.

I would therefore rather turn the Galileo argument on it’s head. When the risks and hazards of greenhouse gases emissions led to the warnings of dramatic climate change, they were not generally accepted. The current high number of scientific noses counted among those who accept the conclusions (inclusive of description of risks and uncertainties) is gained on basis of a similar ongoing process of scientific observations and debate as with Galileo’s and Darwin’s theories, and, presumably, with Einstein’s theories (who is every once in while again proven correct). The examples of Galileo and Darwin support, rather than run counter, against acceptance of the IPCC conclusions.

I agree with the arguments made at the beginning of this discussion on basis of Mr. Koonin’s OpEd. Mr. Koonin warns against taking actions, because according to him the science is not settled. The inaccuracies in his article have already been pointed out. I would like to add two other points.

The first are the observations done in the field. One can always argue that a single storm is not evidence of climate change in action. A single Blackbird breeding a month earlier is not evidence of climate change in action. However, a series of increasing storm intensity, and the advance of spring across the board with two to four weeks is pretty supportive. So are field reports and investigations among residents in for instance in the area where I live, Quang Binh, Vietnam, with climate patterns that are changing, certainly when put into time perspective, which is a crucial difference between the current man-made climate change and natural climatic shifts.

The second is the risk factor. Changing the way energy is produced and consumed does not harm the economy, as a number of recent news articles suggest. Such changes have beneficial side effects that go beyond addressing climate change. Even if you don’t accept the risks and dangers currently projected, the benefits of energy changes in other fields are compelling enough to effect them. If you put that against the risks that downplaying the risks and dangers of climate carries if it still happens to be true – land degradation, diminished agricultural output, biodiversity loss, health problems, to name a few – it doesn’t seem sensible to delay actions.

My take on climate change

Do read the Wall Street Journal article of Mr. Koonin, visit Climate Science Watch and read the discussion. Also, don’t forget to watch an excerpt of the Daily Show of Jon Stewart on You Tube, who made fun of and eventually became angry with a U.S House hearing regarding climate change, comparing the Republican-led session to “pushing a million pounds of idiot up a mountain.”

This Amazing Biodiversity lets us exist – Do we want to lose it to Climate Change ?

The title above is the slogan I had put on the first banner I used for my photo sharing website The World is Beautiful and Fragile. And each photo on that banner had a sentence, in which often the message is that the continued existence of that species can be doubted because of the oncoming effects of climate change. For each species it is a question mark. It is without further study – primary, secondary or tertiary – not always possible to confidently state of a species whether it will adapt to climate change or not. I have since changed the banner, but have kept the introductory text on climate change – and you will see this same elephant looking at us, as if asking: and what about me? Because whether one is careful about predicting the demise of species, or whether one is more outspoken (with or without further arguments), the (upcoming) impacts of climate change are hard to overstate.

We are member of the Web of Life

Whether we like it or not, we are one of the hundreds of thousands of species that inhabit this earth, and we, as a species, rely on the ecological role we play as much as other species. Granted, human populations have over time developed lots of technologies to decrease limiting ecological factors. Food and shelter are obvious examples. From caves to huts to buildings, technology allowed lots of people to escape death from weather events, diseases, or, for instance, predators. The development of agriculture allowed a greater control over the availability of food. Food and shelter then, are just two among many factors that allowed people to live longer and in greater numbers.

All species change their environment to a lesser or greater degree to their benefit. Species that dig holes or building nests are essentially doing the same that people did by building houses: controlling access by predators, harmful temperatures, or e.g. storing food. A number of species of ants predate people in actively controlling temperatures inside their dwellings. As for food, certain species of, again, ants, actively control their food supply, by herding aphids. (See for instance http://insects.about.com/od/coolandunusualinsects/f/antsandaphids.htm)

This mutual beneficial relationship between ants and aphids works by ants eating the honeydew secreted by the aphids, and the aphids being protected from predators by the ants

Yet, no species has moved the limits of ecological factors as much as we did. It may seem to some, therefore, that we have freed ourselves of our ecological role, and that, pried loose from the rest of nature, people can always survive.

Such thinking would be a mistake. Despite technological progress, people are and remain organisms that rely on a myriad of things in our immediate or wider environment. Some clear examples include the food we eat. To some it may appear as if food is not constrained by such factors: people visit supermarkets and buy meat, vegetables, rice, bread and a host of other things. Nevertheless, these are agricultural products, needing soil to grow, and their cultivation is determined by the local climate. Even those limits can be moved. Hydroponics is a system where plants can be grown in a watery environment, not needing soil. But even such systems are not free from diseases, and they still need fertilisers, be that organic or industrially manufactured. And besides, it’s hard to see all wheat, rice, potato and corn fields in the world – major staple crops on which the majority of people rely – replaced by a vast system of hydroponics.

Can we imagine our staples grown worldwide as hydroponics ?

Another example form the micro-organisms in our digestive system, without which we would not be able to digest all the food we eat. Micro-organisms can also make us sick, periodically reminding us of those ties with the rest of nature, as the current ebola crisis grimly shows. And there are a good number of micro-organisms and fungi that allows us food items such as wine, cheese, beer, and spirits. Examples can be found too in recent weather events, where flooding cause damage, death and food shortages, and storms destroy houses and shelters, grim reminders of the discomfort and dangers of living without these.

Climate change

And this brings me then back to climate change. If we are so reliant on other organisms, then we should try our utmost best to keep these other organisms. But despite enormous ongoing conservation efforts, it is increasingly more difficult. Habitats are damaged or destroyed. Invasive species – species that do not belong in a given region, but have been introduced there, and thrive – outcompete native species. Overharvesting threatens the survival of certain species, such as is the case with the bluefin tuna – that has its own commission, the International Commission for the Conservation of Atlantic Tunas – or whales – which have theirs, the International Whaling Commission, on basis of an international convention, the International Convention for the Regulation of Whaling. Nevertheless, as all sorts of projects and programs show, these threats can be countered to a higher or lesser degree.

Climate change, however, has proved sofar to be beyond people’s capacity of arresting its threat by for instance effective behavioural change, or meaningful government policies (i.e. a real global decrease in greenhouse gas emissions). Greenhouse gas emissions are still rising: the World Meteorological Organisation found that in the last decade “the amount of greenhouse gases in the atmosphere reached a new record high in 2013, propelled by a surge in levels of carbon dioxide”. And the world is steadily growing warmer. The famous pause in temperature rise has found to be – as suspected – an expression of the capacity of world’s oceans to store heat. The oceans have gotten warmer, instead of the atmosphere. Once this capacity has been exhausted, warming of the atmosphere will go up, in an accelerated pace.

And this must be clearly said : unless we find the means to suck up enormous amounts of carbon dioxide and other greenhouse gases, climate change cannot be reversedWe can still only try to minimise the changes.

What then can we expect. Sea level rise, of course. Recently, the thawing of an antarctic ice shelf has been assessed as signifying an unstoppable and irreversible process of melt. Also changes in temperatures: record heats and colds have been measured for a number of years. See for instance this map of NOAA with land and ocean temperatures for August 2014:

Red all over

There is hardly an area that is showing the average temperature for August, and the vast majority of territory shows a higher temperature. NOAA goes on to say that “August marked the 38th consecutive August with a global temperature above the 20th century average. The last below-average temperature for August occurred in 1976.” In general the weather has already become, and will be more, unstable with more extremes in heat and cold, drought and excessive rainfall. Just today, an article in The Independent reported on research of Cornell University that concluded that the risks of experiencing megadroughts (droughts that last for 35 years or longer) are now high.

What does this all mean for biodiversity?

The Convention on Biological Diversity says this on its website:

“It is now widely recognized that climate change and biodiversity are interconnected. Biodiversity is affected by climate change, with negative consequences for human well-being, but biodiversity, through the ecosystem services it supports, also makes an important contribution to both climate-change mitigation and adaptation. Consequently, conserving and sustainably managing biodiversity is critical to addressing climate change.”

Deepening all that is something for a next post. For now I just wonder which species will have enough adaptability to maintain ecosystem functions, considering that where species have evolved in the context of slower processes than the current climate change one, which operates on a timescale of significant environmental changes in decades rather than in millennia. And where attention goes, naturally, to easily to see or notice species or groups (mammals, fish, shellfish, agricultural crops), lots of other species or groups don’t get the attention they deserve: fungi, butterflies, bees, bacteria.

Climate change action

The IPCC, Cornell University of the megadrought report, and a host of other authors and institutions predict enormous problems for the coming decades. Agriculture will be severely affected. The food security as we have known it in the developed world since after World War II will disappear. And we haven’t even talked yet about the seas and oceans growing more acid, effecting fish and shellfish populations. Seen from these apocalyptic perspectives, all the ongoing things like the genteel Scottish independence, brutally establishing an islamic caliphate, or e.g. surreptitiously bringing back the Soviet Union, seem like futile struggles, whose importance and realisation will pale once climate change effects begin to bite more intense.

Clearly, it seems, there is reason for climate change action. The UN is trying to lay the grounds for a meaningful global agreement in 2015 as of 23 september. Not everyone is convinced that politicians will do enough. Avaaz, an activist online-petition network, organises an online petition to submit to the UN – which you can sign here – and seeks to galvanise and coordinate protest-events world-wide so you can find one near you to join it.