Sustained and systematic observations of marine ecosystems are needed to understand how the ocean is changing both naturally and as a result of human activities.
Monitoring of oceans is mostly done by research vessels, underwater drones, and thousands of floating sensors that drift with the currents. However, large areas of the ocean remain under-sampled – leaving gaps in our knowledge.
A team of scientists at the University of Exeter suggests that sea animals could fill many of these gaps by transmitting oceanographic information from electronic tags. Animals carrying sensors can do this trough natural behavior such as diving under ice, swimming in shallow water, or moving against currents.
Lead author Dr. David March, of Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall, said, “We want to highlight the massive potential of animal-borne sensors to teach us about the oceans. This is already happening on a limited scale, but there’s scope for much more.”
“We looked at 183 species – including tuna, sharks, rays, whales and flying seabirds – and the areas they are known to inhabit. We have processed more than 1.5 million measurements from floating sensors to identify poorly sampled areas (18.6% of the global ocean surface).”
Professor Brendan Godley, who leads Exeter Marine, said, “By comparing this with gaps in current observations by drifting profiling sensors (known as Argo floats), we identified poorly sampled areas where data from animal sensors would help fill gaps. These include seas near the poles (above 60º latitude) and shallow and coastal areas where Argo profilers are at risk of hitting the land.”
“The Caribbean and seas around Indonesia, as well as other semi-enclosed seas, are good examples of places where Argo profilers struggle because of these problems.”
According to scientists, the data collected by turtles or sharks could also enhance ocean monitoring in other remote and critical areas such as tropical regions, with a large influence on global climate variability and weather.
Professor Godley added: “It is important to note that animal welfare is paramount, and we are only suggesting that animals that are already being tracked for ethically defensible and conservation-relevant ecological research be recruited as oceanographers. We do not advocate for animals being tracked solely for oceanography.”
The study is published in the journal Global Change Biology.