Marine ecologists in UK have shown it is possible to monitor shark populations via environmental DNA (eDNA), whereby a sample of seawater can provide the identifiable 'tracks' of numerous species of shark.

The team, which included scientists from six countries, from Europe and the Americas, took water samples in four sites in the Caribbean and three in the Pacific Coral Sea. Using a process called metabarcoding, the team recovered significantly more shark DNA sequences in less anthropogenically impacted areas.