An approach inspired by military and aerospace techniques has been tested on flapper skate in Scotland
An international team of researchers hope a new method of tracking animals that spend their entire lives underwater could help protect endangered species.
A paper published today [Wednesday 26 November 2025] in Science Advances reveals how a state-of-the-art statistical approach, inspired by techniques used in military and aerospace contexts, can reconstruct animal movements.
The academics behind the paper, led by Dr Edward Lavender of Edinburgh Napier University and the Swiss Federal Institute of Aquatic Science and Technology (Eawag), believe the findings could inform the creation of effective protected areas.
Across the world, electronic technologies such as satellite tags are used to track animals, but their use underwater is limited.
In aquatic environments, passive acoustic telemetry is the prevailing technology – using networks of acoustic ‘receivers’ which listen continuously for ‘pings’ from animals tagged with acoustic transmitters.
Animal-borne sensors like data storage tags, which record individual depths through time, are also used. But integrating the information from these different technologies to reconstruct animal movements in great detail has proved challenging.
The new approach outlined in this paper conceptualises animals as ‘particles’ that can swim around and ‘reproduce’ or ‘dwindle’, depending on the data. The distribution of surviving particles provides a map of the tagged animal’s possible location.
The authors applied this approach to data from the world’s largest skate species: the Critically Endangered flapper skate in Scotland. Growing well in excess of two metres long, this elusive fish roams in the darkness over Scotland’s rugged seabed.
In 2016, the Loch Sunart to the Sound of Jura Marine Protected Area (MPA) was established to conserve this species. By reconstructing its movements, the researchers found that they exhibit high residency in this MPA and should benefit from fisheries restrictions in the region.
The authors were also able to pinpoint hotspots in unprotected habitats, where additional protection may be beneficial. Work continues to refine these analyses and identify critical habitats, including potential egg nurseries.
The study was led by the Swiss Federal Institute of Aquatic Science and Technology (Eawag), based on data collected by the Movement Ecology of Flapper Skate project. It brought together a diverse team of biologists, statisticians, physicists, mathematicians, ocean modellers, conservationists and policymakers from leading research institutes and conservation agencies, including Edinburgh Napier University, the University of St Andrews, the University of Glasgow, the Scottish Association for Marine Science, the Royal Zoological Society of Scotland, the University of Surrey, NatureScot and Scottish government’s Marine Directorate.
It was funded by Eawag, using data made available from projects funded by Marine Directorate, NatureScot and the Marine Alliance for Science and Technology for Scotland.
Lead author Dr Edward Lavender of Edinburgh Napier’s University Centre for Conservation and Restoration Science (CCRS) and Eawag’s Department of Systems Analysis, Integrated Assessment and Modelling said: “This is a good news story for conservation.
“The ability to integrate information from different technologies to map space use and identify movements in essential habitats is a great step forward for conservation science, and it could inform protected area design across the world.
“By integrating multiple datasets we can refine maps, model movements beyond receivers and quantify how long animals spend in specific areas.
“This work strengthens the conservation value of animal tracking data and helps move us towards robust, data-driven design of protected areas.”
Co-author Dr Carlo Albert, of Eawag’s Mathematical Modelling group, said: “From a mathematical perspective, I found this a very interesting problem.
“It was clear that the depth data of a benthic fish on a rugged seabed should contain valuable information about the fish’s whereabouts, but extracting that information was not straightforward.
“It was satisfying to see how accurate and precise the results can be when the right Bayesian inference techniques are combined with an efficient implementation.”
Co-author Dr Jane Dodd, elasmobranch specialist at NatureScot, said: “This work will help us to identify essential habitats, such as egg nurseries, for protected species like the flapper skate.
“This has the potential to deliver increased protection of these areas and effective species conservation.”
Joint senior author Professor James Thorburn of Edinburgh Napier University’s CCRS, and lead of the Scottish Shark Group, said: “This work shows the value in bringing together expertise in different sectors and government to advance our knowledge of how Critically Endangered species use the marine environment.”
Pictures credit: James Thorburn