A new type of non-invasive and highly effective electronic tag is beginning to show its true potential. Capable of working up to two kilometres underwater and having almost zero impact on the animal it’s attached to, the ‘marine skin’ could be a game changer.
Marine biologists have come a long way when it comes to tracking animals underwater. In the early days of the science famed researcher and explorer Jacque Cousteau tracked one of the first marine creatures underwater when he tied a giant red balloon to a sea turtle and followed it around from the surface. Although such an experiment would be frowned upon today, at the time technology was a limiting factor and so it had to do if we were to learn more about these amazing creatures. However over time balloons were replaced with metal identity tags which soon became electronic dive loggers and incorporated much more technology including pH sensors, cameras and GPS capability. But as we have learned more and more about marine animals one constant has remained. The risk that tagging creatures with heavy and invasive equipment can damage, distress and even kill them. But a new type of tag has now been invented that not only removes this risk but can also tell us things its predecessors could not. Named ‘marine skin’ this ground breaking technology could be about to change marine biology in a big way.
What is ‘Marine skin’?
Marine skin is a polymer-based material with integrated electronics, or put simply a plastic tag. Like a standard tag it can track an animal’s movement and diving behaviour as well as the health of the surrounding marine environment. But unlike other tags that are almost exclusively metal based marine skin is lightweight and very flexible, meaning it does drain its host of energy or cause it any discomfort. It is also extremely thin which helps keep animals streamlined which does not restrict their movements and is also why it is referred to as a ‘second skin’.
It was first revealed last year when the initial tests on a swimming crab were published in Nature. The team behind it were from the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia and received international praise for their work. Although making a tag out of plastic seems like a sensible and logical next step for tagging it has proved tricky to incorporate the necessary technology within the thin polymer sheet whilst making it durable enough to last underwater. Therefore their invention has become a major step in the evolution of tagging technology.
Going smaller, further and deeper
In April the team from KAUST released a follow up study published in Small, a nanotechnology journal, and the improvements in their technology in such a short space of time are remarkable. The first difference is that the new marine skin is even smaller and lighter making it even better for the animals it’s attached to. Not only that but whereas the first version was glued onto swimming crabs the new version was attached to sea bass and other smaller fish using a completely non-invasive bracelet or jacket. It is also more efficient and the KAUST team claim the integrated electronics are 15 times more sensitive to its surroundings. This means it produces more reliable readings for things like temperature and salinity of the environmental waters. But most importantly it is even more resilient to damage and degradation. It not only stood up too high salinity when tested in the Red Sea but has also been shown to function at two kilometres underwater which KAUST PhD student Sohail Shaikh says “has never been achieved by anyone”.
Considering how far the marine skin has come in such a short space of time its potential for the future is very exciting. The KAUST team are already planning to incorporate additional environmental sensing capabilities, such as measuring oxygen and carbon dioxide levels and precise geolocation tracking. The next steps will also include testing its effectiveness at tracking marine megafauna such as sharks, turtles, whales and even octopuses. If it does work as well on other animals then it is likely that in the next decade marine skin could become the main tracking method in marine research. What’s more due to its minimal impact on hosts there will be less of a limit to the number of animals that can be tagged meaning tracking data could become exponentially more reliable. Hopefully as time goes by and the technology improves it will become a much cheaper alternative to current technology. One thing is for certain, it will be very interesting to see how marine skin develops in the next few years.