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.
The importance of whales and dolphins in 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.
Seabirds
A study just came out with former NASA climate scientist James Hansen. Therein, he warns that a reduction in the amount of atmospheric pollution could …
Sharks and Rays
Tiger Sharks are found throughout the world’s tropical and temperate oceans. While Great White Sharks steal the glory in terms of Hollywood, Tiger Sharks may …
Latest posts about why the oceans are important
It’s World Coral Triangle Day and I am going to take a different look at this vital region by examining the global scale and intensity of its Animal ImpactWhat is Animal Impact? Without wildlife, Earth would not be habitable for humans, because it's animals that stabilise ecosystems. It’s a fundamental law of nature that animals (and humans) exist because we are the most likely lifeforms to minimise environmental chaos. Animal impact, therefore, is a measure of how much all wildlife is collectively responsible for creating a habitable Earth. The More. There is nowhere on Earth that comes close to its diversity and abundance of ocean wildlife but rather than looking simply at what lives there, we’ll discover the top five reasons to conserve Coral Triangle wildlife and why its animal communities are essential to maintaining a habitable world for all humanity. Because, we can easily get sidetracked into thinking conservationWhy is animal conservation important? Animal conservation is important, because animals are the only mechanism to create biodiversity, which is the mechanism that creates a habitable planet for humans. Without animals, the energy from today’s plants (algae, trees, flowers etc) will eventually reach the atmosphere and ocean, much of it as carbon. The quantity of this plant-based waste is so More is only about saving its animals, when it’s actually what they do for us that matters most of all.
#1 Coral Triangle wildlife captures carbon on a global scale
The critical role of wildlife in stabilising ocean ecosystems is often ignored or grossly underestimated. In the Coral Triangle it is particularly significant because of the enormous biomassThe weight of living organisms. Biomass can be measured in relation to the amount of carbon, the dry weight (with all moisture removed) or living weight. In general it can be used to describe the volume of energy that is contained inside systems, as the size of animals relates to their metabolism and therefore, how much energy they contain and More of animals and the sheer scale and biological diversity of the habitatsWhat is habitat for animals and people? Habitat, hence the word "habitable" describes the natural surroundings in which any animal (or human) lives, that houses basic needs, such as food and shelter. Vegetation, for example, is habitat for animals. On its own, habitat is not necessarily stable or sustainable, which is why it differs from an ecosystem. Habitat in disrepair More. In order to remain stable, four immensely diverse ecosystems: deep ocean, mangroves, seagrass and coral reefs, all have to work in unison. The only way this can work, is if abundant wildlife drives the process, because capture of carbon by the plants alone would only make things less stable.
I’ve summarised this in a bit more detail below (Box 1) and you can read my Marine Natural Values Atlas of Eastern Indonesia (below) if you want to know even more. Animals amplify carbon processes and this in turn, supports the Coral Triangle’s biodiversityWhat is the definition of biodiversity? When we ask, what is the definition of biodiversity? It depends on what we want to do with it. The term is widely and commonly misused, leading to significant misinterpretation of the importance of how animals function on Earth and why they matter a great deal, to human survival. Here I will try to More richness by promoting massive algal growth. The consequence of having so much carbon capture by plants is that this excess also needs somewhere to go – which it does, into mangroves, seagrass beds and coral reefs, which in turn employ yet more animals to absorb the chaos-forming carbon and keep it safely locked away.
The Coral Triangle is abundant with wildlife because this is the mechanism that evolved to stabilise carbon capture, which this region does on a scale greater than anywhere else on Earth. It’s a significant proportion of the world’s uptake and this is exactly why we need to conserve Coral Triangle wildlife.
- The Coral Triangle is the global epicentre of mangrove, coral and seagrass diversity. More than a quarter of mangroves; the most diverse seagrass beds in the world; and three quarters of the worlds corals are proof it is integral to global carbon cycles.
- Left alone, these systems would collapse, as there would be no way for waste carbon to stabilise.
- The region’s abundant and diverse wildlife is the only thing that stabilises these systems. Animals absorb excess carbon back into food chains but the intensity of that effect is also what creates food security and global cooling outcomes.
BOX 1: the role of marine wildlife in carbon cycling The annual activity of abundant marine megafaunaThe largest animals that represent the top of the trophic pyramid. These are the final building blocks in ecosystem structures for maximum entropy production. Megafauna can be measured at any spatial scale. The largest animal that ever lived on Earth is the Blue Whale. In a grassland, spiders could be considered megafauna The term is generally reserved for animals larger More (Oceanic Manta Rays, Blue Whales, Hammerhead Sharks etc.) amplify algal growth through the daily recycling of iron and other limiting nutrientsEnergy and nutrients are the same thing. Plants capture energy from the Sun and store it in chemicals, via the process of photosynthesis. The excess greenery and waste that plants create, contain chemicals that animals can eat, in order to build their own bodies and reproduce. When a chemical is used this way, we call it a nutrient. As we More into the food chainA single thread in a food web illustrating the chain of animals that eat each other. At the base of the food chain are small high-energy (fast metabolism) animals and at the other end large low metabolism animals. An example would be whales eating krill that eat plankton that eat algae. Or lions that eat gazelles that eat grass. More [2]. This then supports a whole range of animals that seasonally migrate to the Coral Triangle and congregate together. This community-level amplificationAmplification (of nutrients and energy). Animals consume plants and other animals and in doing so, reintroduce important energy-containing nutrients back into the environment, at even higher concentrations and in patches. Amplification of energy is driven by migration and happens at every scale, from insects moving daily in and out of your vegetable patch, to African wildebeest herds and the seasonal More allows even more algae to grow but when they die, that carbon is reintroduced in even greater abundance and risks the stability of the system. This creates a paradox. Where does the excess go? Some of it settles onto the seabed but much of it gets whipped up by strong currents that swirl around the region’s 20,000 islands where it could become pollution if it wasn’t for the action of other animals in neighbouring ecosystems. Mangrove soils can be three metres deep and store more carbon than tropical forests [4]. Like the ocean, mangroves and seagrass depend on animals to maximise efficiency and minimise waste carbon. Dugongs and Green Turtles increase seagrass density through grazing – meaning even more animals can survive there, meaning even more carbon is processed. Similarly, studies on mangroves have found between 66 – 128 leaf-eating species and in one study, from the Andaman Islands and Nicobar, an overall total of 276 insects [5]. Almost all the sediment locked below mangroves has to pass through ship worms and crustaceans first.
#2 It cools the global oceans and atmosphere
Ocean wildlife is critical to the process of atmospheric cooling and nowhere is this better illustrated than in the Banda Sea, situated in the Coral Triangle’s south. The entire planet’s ocean circulation flows through here, equivalent to the volume of all the world’s rivers combined. The Banda Sea has a maximum depth of 7,440m and traps water for a year, where it is mixed, especially during the southeast monsoon. By the time it reaches the Indian Ocean it is richer in nutrients, less saline and cooler by about 0.5°C. During upwelling events, the Banda Sea’s surface temperature can be a remarkable three degrees cooler!
Just the physical effects of mixing by all vertebrates swimming vertically up and down through the water column can provide up to a third of all ocean mixing, equivalent to tides and wind combined (Box 2). Coral Triangle animals are significant components of processes that regulate planetary warming and the effects can be felt across most of the Earth, at least from the Pacific in the west, as far as Africa and the Middle East. The activity of wildlife is the difference between catastrophic bushfires in Australia and rainfall in China, India, East Africa and even as far as South America.
- The Coral Triangle’s wildlife is responsible for up to a third of ocean mixing in a system that cools the global atmosphere, minimising risk of bushfires, drought and flooding.
- The significant role of animals in climate regulation is missing from any ocean-climate models for the region and does not feature in conservation narratives for the Coral Triangle.
BOX 2: the role of marine wildlife in ocean cooling Just the physical effects of mixing by all vertebrates swimming vertically up and down through the water column can provide up to a third of all ocean mixing, equivalent to tides and wind combined [6]. Turbulence from fish swimming has been compared to the effect of major storms[7]. Large marine vertebrates like tuna and whales have a disproportionate impact on mixing, because their activity is concentrated at predictable and reliable locations. This animal impact affects two global climatic processes: the Indian Ocean Dipole (IOD) and the Southern Ocean Oscillation (usually referred to as El Niño and La Niña). In 2019, there was a strong positive IOD which led to a drying of the Australian continent and catastrophic bushfires. Ironically, the activity of Blue Whales and Hammerhead Sharks in the Banda Sea that year was intense and prolonged, which would have made the bushfires worse. Again, there is the paradox. If more animals make things worse, why do stable ecosystems need abundant wildlife? The systems are self-correcting. The whales are part of a process that goes into over-drive to reduce planetary warming but like any refrigeration process, there has to be somewhere for the heat to dissipate and in this case, it was spread out across the Australian continent. The impact of the IOD influences climate across most of the Earth, at least from the Pacific in the west, as far as Africa and the Middle East. As we lose abundant wildlife from places like the Coral Sea, it creates wilder fluctuations in climate and remaining animals have to work harder. We are losing the animal-driven systems that we depend on … because we are animals and originally evolved as part of the same stabilisation processes.
#3 Wildlife conservation in the Coral Triangle creates global food security
Carbon cycling and ocean cooling are both directly linked to food security because (as described in #1 and #2, above) climate change causes global weather patterns to change, which affects farming all over the world. Seabird colonies as well as surface-feeding fish, whales and dolphins, also create chemistry that influences rainfall on a continental scale. Predictable and stable rainfall patterns are essential for our agriculture. If we conserve Coral Triangle wildlife, we will have a better chance of knowing when and where to grow food, which is central to all our economies.
The Coral Triangle has a density and diversity of wildlife greater than anywhere else on the planet and this means it also directly creates conditions for food production. Wildlife transfers, amplifies and concentrates resources on every possible scale, creating a precision and intensity of effect that we can never hope to replicate artificially. In the case of fisheries, the region is of huge significance.
Marine ecosystems stabilise where there is a natural abundance and diversity of wildlife, which is proportional to the physical power of the system. Big, common Coral Triangle animals like tuna, whales, whale sharks, manta rays and seabirds hold together the infrastructure (the biodiversity) that maintains all other ecosystem services. The remarkable richness of the Coral Triangle’s wildlife tells us that this is a critical epicentre for global food security.
- Marine vertebrates are vital for healthy functioning coral reefs, fisheries and marine ecosystems, driving surface nutrientA substance that contains the raw materials for life. At a chemical level, these are contained inside compounds that are absorbed into the body and essential energy-containing molecules are extracted, so that energy can be transformed into other chemical processes that use the energy for living. More processes and generating conditions for seasonal development of pelagic fisheries.
- Transportation of nutrients by seabirds back to land is vital for coastal ecosystems, coral reef and fish.
- Marine animals transfer(of nutrients) the thing that sets animals apart from plants, is that they can move. Some of the biggest migrations on Earth every day, are the movement of insects like caterpillars, from the stem of a plant to a leaf and back, before turning into butterflies and transferring the energy elsewhere. Large-scale migration of grazing animals and migratory songbirds moves More, amplify and concentrate nutrients on a local and global scale, at the right time and place, creating enriched ocean life.
- The Coral Triangle sustains Indian Ocean ecosystems through export of cooler, nutrient-rich water, which is the result of nutrient amplification and ocean mixing by wildlife.
- Tropical seabirds influence continental rainfall via cloud seeding mechanisms.
#4 It supports global economies and poverty alleviation
The region’s animal impact on climate and food security is globally significant and this translates into international economic empowerment, if we conserve Coral Triangle wildlife. This benefits farmers in Australia and South America, fishers in Central Asia and the Solomon Islands and tourism operators over half of the world. We know this because the impact of wildlife decline is already having marked effect on our lives by gnawing away at the stability of our economies.
In order to protect ourselves from ecosystem collapse, we need to conserve ocean wildlife everywhere but the Coral Triangle is particularly important. But that also means alleviating poverty in the Coral Triangle – because people who can’t feed themselves, cannot be expected to spend time and money conserving wildlife for us. A disproportionate number of people who are custodians for this critical ocean landscape are living below the poverty line. There are 2.25 million local fishers who depend on healthy seas to make a living but are losing out to industrial fisheries … fifty times more local people are dependent on those ecosystems as their home.
- Wildlife conservation, food security and poverty alleviation are integrally linked.
- Stable animal-driven ecosystems are essential for supporting global ecosystem services, as well as economic viability through fisheries and agriculture.
- The carrying capacityThe population of animals that a steady-state ecosystem can support. It’s the number that results when total mortality equals total birth-rate. Populations aren’t evenly-distributed to carrying capacity depends on there being both population sources and populations sinks that balance each other out. This is why it can never be said that “animals can move somewhere else”. Loss of critical habitat More for people globally and locally, depends on maintaining wildlife in the right abundance and proportions.
- Millions of people who are custodians of some of the most important places are already living well below the poverty line.
#5 Coral Triangle wildlife builds global ecosystem resilience
Ecosystems are dynamic by nature, so there have to be areas that act as sources of life and others as sinks – you can’t have a system producing all the time, unless there is somewhere for it to end up.
We’ve have established that the Coral Triangle has overwhelming and globally-significant importance for climate, food and our economy … and that’s why we need to conserve Coral Triangle wildlife. We know other oceans benefit from the export of wildlife from the Coral Triangle because offspring of species like Leatherback Turtles travel the entire Pacific. Abundant seabirds migrate from the Arctic and vast herds of whales and dolphins migrate between the Pacific and Indian Ocean. The quantity of species and connectivity with other reef systems in the Indian Ocean and Pacific places the Coral Triangle as the source from which most other ecosystems renew. The region acts as the greatest safeguard against ocean ecosystem collapse.
- The region has almost three quarters of all the world’s hard coral species
- In an area only 10% of the size of the Great Barrier Reef you can find twenty species of marine mammal (Dugong, whales and dolphins).
- A third of all the world’s reef fish species occur here. In 2012, fish scientist Gerald Allen counted 374 species at one location in about an hour.
- It has a quarter of all mangrove forests on Earth and the world’s most diverse mangrove and seagrass communities.
- The region is connected to other parts of the world by enormous annual and seasonal migrations of wildlife.
Why we need to conserve Coral Triangle wildlife
We tend to imagine that spectacular ocean currents, mountains, winds and weather formations are all-powerful ecosystem drivers but they’re not. They only kick-start processes. As humans, we live among the animal-led mechanism that sits above that. It’s the tendency of animals to congregate and amplify living conditions that made it possible for humans to derive enough sustenance to exist. It’s why we exist. Our dependence on the food security and climate of the Coral Triangle is a byproduct of the role all animals play in stabilising ecosystems.
The scale and intensity of animal impact in the Coral Triangle wilderness is like nothing else on Earth. The effect is to cool the planet, influence the weather globally and contribute to the stability and security of our food industries. We cannot survive without the Coral Triangle.
We might view the Coral Triangle as a place where animals live and try to conserve the environment for their sake. That’s fine but it belies a far greater importance. We actually need to conserve Coral Triangle wildlife because it’s animals that protect the environment for all our sakes. Their impact translates into stronger and more resilient economies.
At least as far as human survival is concerned, everything we need, is driven by animals!
The Coral Triangle is a part of the world that none of us can afford to lose but we can do more to explain the critical importance and integral connection we all have to its wildlife.
Read the trip reports
Here are some trip reports from recent expeditions I’ve led.
Marine Natural Values of Eastern Indonesia
Here is a technical report I wrote about Marine Natural Values of Eastern Indonesia, which is a more detailed and fully referenced scientific overview of the role of marine biodiversity in the heart of the Coral Triangle.
- Coral Triangle and countries participating in the Coral Triangle Initiative, based on (4 March 2014). “Developing Marine Protected Area Networks in the Coral Triangle: Good Practices for Expanding the Coral Triangle Marine Protected Area System”. Coastal Management 42 (2): 183–205. DOI:10.1080/08920753.2014.877768.
- Martin, J.H. and S.E. Fitzwater, Iron deficiency limits phytoplankton growth in the north-east Pacific subarctic. Nature, 1988. 331(6154): p. 341-343.
- Jennerjahn, T., Biogeochemical response of tropical coastal systems to present and past environmental change. Earth-Science Reviews, 2012. 114: p. 19–41.
- Donato, D., et al., Mangroves among the most carbon-rich forests in the tropics. Nature Geoscience, 2011. 4: p. 293-297.
- Burrows, D., The role of insect leaf herbivory on the mangroves Avicennia marina and Rhizophora stylosa. 2003.
- Dewar, W., et al., Does the marine biosphere mix the ocean? Journal of Marine Research, 2006. 64.
- Huntley, M. and M. Zhou, Influence of animals on turbulence in the sea. Marine Ecology-progress Series – MAR ECOL-PROGR SER, 2004. 273: p. 65-79.