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From bots targeting coral-eating starfish to soft, fishlike machines monitoring the situation via a Super Nintendo controller, these are the robots saving our reefs.


With temperatures gradually increasing as part of climate change, coral reefs are literally being cooked. Combine this with other threats such as water pollution and the situation is critical.

Today, almost two-thirds of the coral on Australia’s Great Barrier Reef – the largest reef system on Earth – has been damaged. Reefs in the Caribbean and North Pacific have also been affected, with others, including those in less tropical climates, again at risk.

Meet the inspirational robots protecting coral reefs

Credit: Ioannis Oikonomou


Scientists are looking at new solutions using robotics to preserve coral reefs

But scientists are now looking at a new solution, one that’s already assisting the conservation effort: robots. Not only can these smart machines dive to task for us, but they can also help us manage these vast underwater areas much more efficiently.

QUT’s new COTS killer

Australia’s Great Barrier Reef is currently in the midst of a crown-of-thorns crisis, with thousands of these deadly starfish eating away at the precious coral. Normally they play a vital role in maintaining coral diversity, but when outbreaks are coupled with the ongoing coral bleaching crisis, stopping these COTS is a priority for reef conservation efforts.

Enter RangerBot.

The brainchild of the Queensland University of Technology (QUT) robotics team, this autonomous underwater vehicle, funded by Google, is a downsized, more cost-effective version of the team’s previous model, COTSbot – the world’s first underwater robot to kill these marine pests.

As well as monitoring the state of our coral reefs, RangerBot, like COTSbot, will be able to cull these destructive starfish by administering them with a fatal dose of bile salts – a task that’s currently taking hundreds of human hours.

Dubbed the ‘Swiss army knife’ due to its multifunction capabilities, this smart marine robot is equipped with innovative vision-based technologies as well as machine learning software to prepare it for the task ahead.

“We generated models of the starfish by training the robot on hundreds of thousands of images collected from many reefs under different lighting and visibility conditions. These models allow the robot to quickly and robustly detect the starfish in new previously unvisited locations on the reef.”

—Matthew Dunbabin, Robotic Vision researcher

The latest version of the design is currently being tested off Queensland’s Lizard Island. In the future it’s hoped RangerBot’s duties will extend to replanting coral in degraded reef systems.

The stealth coral photographer

A soft, agile robotic fish operated using the controller of a Super Nintendo: it sounds more like a video game than a serious conservation project. However, SoFi (short for soft fish) has a critical role to play: helping scientists more effectively observe at-risk reef environments.

Developed by the Massachusetts Institute of Technology (MIT) Computer Science and Artificial Intelligence Laboratory (CSAIL), SoFi offers a unique advantage to other marine robots. Gliding gently through shoals of fish and alongside reefs, it’s able to take high-res photographs and videos through a small nose cam, all without damaging the coral or disturbing the inhabitants, who think it’s one of them.

Internally it’s equipped with a buoyancy sensor, DC motor and a comms receiver. The tail is made up of a series of chambers that can be inflated at intervals to mimic a natural swishing movement and enable it to move forward, back, up and down at varying speeds.

47cm long and weighing 1.6kg, SoFi can reach depths of up to 18m and swim without a motor for a maximum of 40 minutes controlled by a diver up to 21m away. For pressure protection, the Nintendo controller is enclosed in a rigid oiled case.

SoFi has already been tested in the waters of Fiji’s Rainbow Reef, as well as in a pool at MIT, proving she has the skills needed for the task.

“We view SoFi as a first step toward developing almost an underwater observatory of sorts. It has the potential to be a new type of tool for ocean exploration and to open up new avenues for uncovering the mysteries of marine life.”

—Daniela Rus, CSAIL director (via MIT News)

Send down the robot surveyors

In 2017 the Australian Institute of Maritime Science (AIMS) was using a surfing robot developed by Boeing subsidiary Liquid Robotics called Wave Glider to monitor the Great Barrier Reef at surface level. Today AIMS is diving deeper and breaking new ground (well, ocean) once again.

The modified Blue ROV2, Blue Robotics’ remotely operated underwater vehicle, is able to monitor reef health by locking on and following a transect line – a traditional survey technique – using  semi-autonomous navigation, up to depths of 100m.

Equipped with a hyperspectral camera, it can capture more than 270 bands of colour information, way beyond human eye capabilities. This enables it to view reefs at deeper levels to produce detailed floor maps and identify water depth and coral bleaching.

It also delivers in other ways, including speeding up data collection and processing, and increasing scope and accessibility.

ROV2’s capabilities were recently demonstrated during a two-week trial, a trial that included simultaneous night-time missions with a large hyperspectral camera-fitted aerial drone.

“Robotics helps us to monitor larger and new sections of the reef in areas that would otherwise be dangerous to divers. These robots will soon be helping to free up our marine science researchers to do the important work of looking at how to help support these reefs”.

—Melanie Olsen, AIMS Technology Transformation leader

Cold water coral reconnaissance

Exotic reefs located in tropical waters aren’t the only habitats at risk. Climate change is also putting deep-sea or cold-water coral environments in danger. While they occur across the Earth, many of the largest beds are found in the far-north and far-south Atlantic.

Once again, smart machines are on the case. In the UK, a fleet of robotic submarines has been used by the National Oceanography Centre (NOC) in partnership with Defra to map the vulnerable cold water corals off the Cornish coast in south-west England – The Canyons MCZ.

These deep-sea diving marine robots, named Isis ROV, can dive to depths of up to 6,500m, lowered by a steel cable from the boat above. Once they hit the bottom, they’re guided by remote joystick around the dark sea floor, capturing images of the uncharted ocean abysses using five cameras fitted with powerful lights. They can also use their mechanical arms to collect samples.

By helping scientists monitor and explore these reefs, these subs are playing an important role in the protection of deep-sea corals. Namely, helping humans make more informed decisions about site management.

“The Canyons MCZ is a challenging site for us to survey, as it is in deep water far from land and has a complex and rugged landscape. The equipment and expertise provided by the NOC enabled us to gather high-quality data from this important site in a cost-effective way.”

Dr Carole Kelly, Marine Evidence Manager, Defra

Credit: Ioannis Oikonomou


Protecting our world’s coral reefs remains a huge challenge. Are robots the answer? 

Meet the inspirational robots protecting coral reefs

Protecting our world’s coral reefs remains a huge challenge.

While scientists are working on a range of other applications for coral protection, from coral nurseries and reef sun shades to cloud manipulation and 3D printed corals, having these smart machines by our side, helping us monitor and protect these fragile underwater systems, should significantly improve our chances of making a positive impact.