by simon
Why are the oceans important? The importance of wildlife.

The importance of the oceans, their wildlife and ecosystems

The land and oceans are part of one system: Earth. So when we ask, why are the oceans important? We’re asking about our own future. Life began in the ocean billions of years before the first plants or animals colonised land. Oceans regulate the state of our atmosphere because they are 99 per cent of the volume of living space for animals and wildlife is the mechanism that drives stability.

Climate change has always been the symptom of biodiversity loss … that’s to say, the breakdown of the complex connectivity between lifeforms that allows Earth to flex in response to changing conditions. Ocean wildlife has, for the large part, acted as a buffer against the most catastrophic effects and since about fifty million years ago, has kept our climate quite stable.

Industrial fishing only happened recently in our planet’s history and this reduction in the abundance of wildlife represents our greatest challenge for survival.

Below you will find a range of articles designed to inspire an understanding of the magnitude of animal impact on our oceans.

What’s more important, the ocean or the land?

The importance we bestow on the land is anthropocentric because we live there. It’s naturally important to us that we protect it. Nonetheless, if life in the ocean dies, we suffer irreversible changes to land-based ecosystems and climate.

In this article, we take a look at many of the ways that land and oceans are linked together.

The answer to the question, ‘why are the oceans important’, is that we live on the land but the oceans regulate Earth’s temperature. The oceans are equally vital to the land we live on.

Latest posts about why the oceans are important

The importance of wildlife: Animal Impact. Bumphead Parrotfish. Drawing by Simon Mustoe.

How many animals does an ecosystem need? There is an article on the Australian Academy of Science blog titled ‘What would happen if a fish went extinct on the Great Barrier Reef?‘ about the role of animals in the functioning of coral reef ecosystems. Thank you @ProfTerryHughes for sharing on Twitter.

In ecosystems, each animal plays a role and their functions are partitioned. This seems rather obvious. When you consider that if all animals had exactly the same function, there could be no ‘ecosystem’. That would be like running a farmers’ market with farmers but no delivery personnel, no people to put up the market stalls, no stall-holders or customers. Like economies, ecosystems cannot exist without functional animal diversity.

How many animals does an ecosystem need?
The Bumphead Parrotfish is one example of a highly enigmatic species that performs a significant ecosystem function, acting like the elephant of coral reefs, selectively breaking off huge chunks of coral to digest the algae within. By doing this, each animal recycles about five tonnes of coral each year. Drawing by Simon Mustoe.

It’s a fundamental law of nature that animals exist because they are the most likely lifeforms to minimise environmental chaos.

Remember, all ecosystems (and economies) are animal-driven, because wildlife is the mechanism that builds them. The existence of animals and the environment is part and parcel. This is because it’s animals that stabilise the free surplus energy that primary producers make. Otherwise the system crumbles and animals can’t exist.

It’s a fundamental law of nature that animals exist because they are the most likely lifeforms to minimise environmental chaos. If we remove animals, the ‘eco’ part (which in ancient Greek was oikos and meant the combination of family, household and property) is lost. Any such system collapses.

Results of the study on animals and ecosystems

The Australian Academy of Science blog refers to a study done in 2014 [1] that looked at how many coral reef fish perform certain critical functions. The researchers looked at coral reefs from the western Indian Ocean to the eastern Atlantic. These are habitat for a total of 6,316 fish species.

The scientists categorised the fish based on their characteristics. For example, size, mobility and diet. This resulted in 646 different groupings e.g. one group was fish that are large, pelagic, plankton feeders; another small, nocturnal, grazers and so on. Each of these groups relate to a particular niche, which is another way of saying, how an animal makes a living.

The study revealed that for nearly 40% of these categories, only one fish species was connected to related ecosystem services.

The ecosystem role of fish on coral reefs

Go back to the market analogy. How many grocers are there? How many book sellers? How many people are employed to erect the stalls and take them down each day? How many van drivers … for specific products? How many market managers, admin staff and so on. The list of ‘animals’ needed to minimise disorder in something as simple as a weekly market is surprisingly large but still, the number of people responsible for specific roles is one or two at the most.

The results of the coral reef study, therefore, should come as little surprise – the fact it may, could reveal how little most of us understand about how ecosystems work or our own animality, since we construct economies on the same principles and wouldn’t for a moment imagine that sacking van drivers that bring food to a farmers’ market would be a sustainable option.

Another outcome of the study is an indication of the scale and intensity of the impact animals have on ecosystems.

What makes the study all the more remarkable is that systems like coral reefs have practically infinite complexity, yet this shows they can be maintained in working order by only a few thousand species … based on the partitioned roles and action of a few individuals, across most of the planet’s coral reef ecosystems.

We should not forget that animals living in healthy ecosystems contribute to their stability, despite having such massive impact. Wildlife doesn’t ‘feed on’ habitat, it has an integral role in the creation and preservation of its environment. It has to be that way, or else the ensuing ecosystem chaos and collapse, would cause any species to go extinct.

If people were to consume an average box of cereal every two weeks, it would take the population of Australia 577 years to consume an equivalent weight in cereal.

This is nicely illustrated via the case of the Bumphead Parrotfish.

The remarkable Bumphead Parrotfish

There may be 3.9 million Bumphead Parrotfish fish in the world [2] and each animal consumes about five tonnes of coral a year [3]. With sand weighing about 1.6 tonnes per cubic metre, this means the population as a whole is processing 122 million cubic per annum. If people were to consume an average box of cereal every two weeks, it would take the population of Australia 577 years to consume an equivalent weight in cereal.

The Port Phillip Bay Channel Deepening Project in Melbourne, Australia, was a three-year program to deepen channels for larger ships and dredged 22.9 million cubic metres of material, creating an imprecisely-understood level of permanent and irreversible ecological impact. In the same three years, Bumphead Parrotfish would have created 366 million cubic metres of coral reef erosion, contributing to the healthy functioning of an environment and cost us nothing.

The importance of animals for ecosystem stability

There is nothing man-made that is anywhere near as exquisitely constructed as an ecosystem that animals build, or provides as much equity for survival. Nothing we engineer is able to reduce environmental disorder, maximise efficiency or provide as many jobs, as elegantly as a coral reef.

Furthermore, the only way to reengineer ecosystems is to set the same animals to the task as created them in the first place. There is no other solution. There is no way a single species – human – alone, can recreate this complexity without crushing a system’s stability while we do it. There simply aren’t enough of us … in the case of coral reefs, we can’t breathe underwater and we don’t have the functional ecology to be able to eat eat coral, cultivate-graze algae or defecate sand like a Bumphead Parrotfish.

This should give us all pause for thought, because these rules don’t just apply to coral reefs. Every ecosystem works in a similar same way and we will depend on all other animals to help minimise environmental disorder if we are to have a future on Earth.


Spotlight


Graph titled ‘Functional diversity of fish’ showing that most reef jobs are performed by just one species.

From Australian Academy of Science blog titled ‘What would happen if a fish went extinct on the Great Barrier Reef? Graph showing the functional diversity of fish communities in the Indo-Pacific region, which includes the Great Barrier Reef.


Scientists on Ningaloo Reef have just calculated that the amount of coral consumed by a Bumphead Parrotfish in a year could even be as high as 13.42 tonnes/ha.

References

  1. Mouillot, David & Villéger, Sébastien & Parravicini, Valeriano & Kulbicki, Michel & Arias, Ernesto & Bender, Mariana & Chabanet, Pascale & Floeter, S. & Friedlander, Alan & Vigliola, Laurent & Bellwood, David. (2014). Functional over-redundancy and high functional vulnerability in global fish faunas on tropical reefs. Proceedings of the National Academy of Sciences of the United States of America. 111. 10.1073/pnas.1317625111.
  2. Kobayashi, D.R., et al., Bumphead parrotfish (Bolbometopon muricatum) status review. 2011.
  3. Bellwood, D., A. Hoey, and J. Choat, Limited functional redundancy in high diversity systems: Resilience and ecosystem function on coral reefs. Ecology Letters, 2003. 6: p. 281-285.
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