Scientist have just discovered a new way to identify what type of sharks live in an area without even seeing or capturing the shark. The results were published in Science Advances.
A team of researchers have filtered seawater and then analyzed the DNA in the water to identify the exact species of shark in the area.
The finding is a thanks to an emerging field of study known as environmental DNA or eDNA. Marine researchers used this new ability in the waters around the New Caledonian archipelago in the Pacific Ocean and the results were pretty astounding.
Scientists decided to test the new method after years of visual surveys have left scientists worried that some species completely disappeared from areas where they were once abundant. The results of the study showed that eDNA was able to detect 44 percent more shark species than traditional methods.
As well, the team detected the presence of more shark species in just 22 samples of seawater filtered for DNA fragments than observed during 3,000 dives and 400 baited videos in New Caledonia. The results were consistent in remote areas along pristine coral reefs and near more impacted areas where sharks are scarce.
“We have all been surprised by these results,” said FIU marine scientist Jeremy Kiszka, a co-author of the study. “It’s exciting to know how useful this tool is, particularly to monitor the presence of rarer and more elusive species, which potentially includes endangered species. We really hope to expand our efforts to identify critical habitats for endangered marine species using this technique.”
New Caledonia waters have been heavily impacted due to human activity and the sharks that were once abundant in these tropical waters have become very scarce.
The new technique may turn into one of the most important tools in shark conservation as scientist will be able to identify and track where sharks are going to better protect certain areas of our ocean. The more we understand sharks, the more we can help them bounce back to healthy numbers.