Link, share, follow: The world’s newest data-gatherers are sharks, storks, seals

In the 1850s, leeches were used to predict violent storms. They were kept in jars of rainwater, where they triggered literal alarm bells when they struggled to the surface in search of oxygen, as the atmospheric pressure around them dropped.

The tempest prognosticator was an ornate brass-glass-and-mahogany device meant for use by the wealthy, in their drawing rooms. As it turned out, keeping the leeches healthy was a bigger challenge than it was worth.

And soon the world had moved on, to more finely tuned instruments that began to unlock secrets behind some of Earth’s most powerful forces, from magnetism and earthquakes to storm systems and tides.
Now, as we seek new kinds of information in a rapidly changing world, science is circling all the way back to bio-monitoring.
Let’s start really small. In 2021, clams in a Warsaw reservoir were fitted with tiny sensors that alerted officials when heavy metals or pesticides were leaching into the city’s drinking-water supply. When exposed to such pollutants, the shellfish clam up, setting off the alarms. Mussels have been tasked with the same job in Minneapolis for more than a decade.
Scaling up, in the cold depths of the Antarctic Ocean, trackers placed on elephant seals have helped oceanographers survey hard-to-access spaces such as coastal shelves. Tiger sharks, migrating storks and Weddell seals have similarly been deployed as unknowing data-gatherers.
It helps that the tags have improved dramatically. They have morphed from clunky devices with relatively short battery lives of about six months, to solar-powered sensors that can weigh as little as 2 gm, and never exceed 3% of the total weight of the animal. Some can even draw from the kinetic energy of the animal’s movements, and are designed to transmit data through a creature’s lifespan.
Could such sensors, gathering readings in real time, read and reprogrammed remotely, be used to create an Internet of Animals, to help us assess real-time changes in our oceans, skies and biomes? Take a look at ongoing efforts and recent successes.
New worlds
Tiger sharks began behaving rather strangely in the Atlantic Ocean off the coast of the Bahamas, in 2016. These large predators tend to hunt close to the shoreline. So when they started moving away from it, marine biologists at the not-for-profit organisation Beneath the Waves (BTW) became curious enough to attach 360-degree cameras to the fish, to see what was drawing them away.
What they discovered, and eventually mapped with the sharks’ help, was 66,000 to 92,000 sq km of seagrass ecosystems that satellite images of the subsea terrain had not revealed (and still can’t see).
This is the world’s largest known seagrass ecosystem, a 2022 paper published by BTW in the journal Nature Communications stated. “Since seagrass beds are excellent sources of capturing, or sequestering, carbon (~17% of the ocean’s carbon annually), this discovery provides the world with a better idea of the ocean’s capacity to store carbon that would otherwise be held in the atmosphere,” said a statement by BTW.
Darker depths
Deep-diving Weddell and elephant seals have been helping map the floor of the Antarctic shelf, with the result that oceanographers are now redrawing estimates of how deep the ocean is here, and are adding underwater features to existing maps, including a marine canyon near the Vanderford Glacier.
In a study published in the Nature journal Communications Earth & Environment in August, researchers at the Institute for Marine and Antarctic Studies (IMAS) of the University of Tasmania reported that the seals were diving to levels 1,000 metres deeper than where existing estimates placed the ocean floor.
Even more revealing, there were channels of warm water here, the sensors reported; a finding with severe implications for ice shelves and ice-shelf cavities, amid rising ocean temperatures.
“If we can find out exactly where the water accesses the underside of the shelves, we’ll also be much better placed to quantify melt rates, freshwater input into the ocean and other variables that affect our future oceans and climate,” study co-author and IMAS ecology and biodiversity professor Mark Hindell said in a statement.
Animals first?
Researchers of ecology and evolutionary biology at Yale University believe that existing methods of collecting weather and climate data could become outdated as we learn to leverage sensors better, to draw data and insight from animals on the move.
In a paper published in the journal Nature Climate Change in September, the researchers showed how “active environmental sentinels” could close critical data gaps by measuring air temperature, pollution, ocean salinity and a range of other metrics in real time, offering a crucial advantage over static traditional systems already struggling to do the job in a climate-change world.
Monkeys bearing GPS sensors, for instance, can relay information about temperatures on the ground beneath a cloud-covered jungle canopy. Sensors on mountain goats could provide real-time data on temperature fluctuations in mountainous regions where weather stations cannot be built. Storks could offer in-depth readings of windspeed strength and air movements above oceans, with implications even for flight paths and turbulence.
And domestic animals such as cows, sheep and dogs could warn against earthquakes, through changes in their behaviour, up to 20 hours before the tremors struck.
In 2020, researchers from the Max Planck Institute of Animal Behavior and the Centre for the Advanced Study of Collective Behaviour at the University of Konstanz, studied the unusually high activity levels in farm animals before earthquakes. It is possible that their fur helps them sense the ionisation of the air caused by changes in ambient pressure, or that they can smell certain gases released before an earthquake.
Further studies could determine what conditions tell birds to lay fewer eggs in years before a complex weather phenomenon such as El Niño, or build their nests higher up before floods. (One explanation involves the theory that we live in a simulation, but that, of course, is an entirely different area of study.)
The future
It’s a plan so audacious, it’s been named ICARUS (the International Cooperation for Animal Research Using Space).
Researchers Martin Wikelski and Uschi Muller at the Max Planck Institute of Animal Behavior are testing an experimental tracking system that will begin data collection in October, using sensors attached to animals and birds around the world — and a receiver fitted onto a very small satellite, named CubeSat.
Scientists will be able to download data and remotely reprogramme any or all of the sensors.
CubeSat will rotate in low-earth orbit, allowing it to circumvent the planet multiple times a day. As a result, it can gather data from around the world, bringing scientists fresh updates from isolated deserts, polar ice fields, oceans and skies.
In a first phase carried out in March 2021, the solar-powered sensors (which weigh less than 5 gm) were deployed across 15 species, including songbirds, rodents and fish.
What the researchers aim to eventually create is an “Internet of Animals” that offers an overview of individual readings and movements, and uses such data to predict, track and mitigate aspects of climate change, biodiversity loss, disease and other threats to human and non-human populations.
Ships could potentially be told when to reduce speed, for instance, to avoid collisions with colonies of whales. Zoonotic data could track the emergence and spread of new viruses.
The real-time connection of disparate pieces of information would “(allow) us to identify cause and effect, and to ultimately make predictions about natural phenomena that we previously didn’t understand,” Wikelski said in a statement.