A technique from forensic science is set to transform the way researchers track birds، daily mail reported.
Scientists have found that a single tail feather can reveal a penguin's migration over many hundreds of miles.
This plumage acts as a 'chemical passport' which carries a memory of all the locations and is as accurate as using an electronic tracker.
Researchers used the technique to uncover exactly where more than 100 of the birds swim in search of food، even though only half that number were fitted with tracking devices.
It works because the penguins feed on krill which carries the chemical signature of the part of the ocean where they live.
When the penguins eat the krill، they incorporate krill chemistry into their own which gives experts clues into these bird's incredible navigation abilities.
This ability to track their whereabouts is crucial for conservation efforts and unlike electronic tracking devices it is not invasive for the animal and the feathers are not hard to retrieve.
'You can say، penguins 'are where they eat،' because a geochemical signature of their wintering area is imprinted into their feathers،' said lead author of the study Dr Michael Polito from Louisiana State University Department of Oceanography & Coastal Sciences.
Chinstrap and Adélie penguins are part of the family of 'brush-tailed' penguins named after their approximately 15-inch long (38cm)، stiff tail feathers.
These birds shed all of their feathers after each breeding season and before they migrate to their oceanic wintering grounds.
However، their long tail feathers continue to grow well into the winter when penguins are at sea.
Researchers attached tags to 52 adult Chinstrap and Adélie penguins at their breeding colonies in the South Shetland Islands، 75 miles (120km) off coast of Antarctica.
They retrieved the tags the following breeding season to determine where the birds went over the winter.
When they retrieved these tags، the researchers also took a tail feather grown over the winter from each tracked penguin and from 60 other penguins that had not been tagged.
The scientists were able to identify the unique chemical signatures of penguin's wintering areas in the ocean based on the coordinates from the tags and the data from the feather analyses.
Researchers were then able to deduce where the other penguins that had not been tagged went over the winter based solely on the analyses of their tail feathers.
'This novel approach could be applied to different tissues from a wide variety of marine animals that migrate over long distances including seabirds، sea turtles، seals and whales،' Dr Polito said.
'Using stable isotope forensics to increase the size and scope of animal tracking studies will help us to better understand these charismatic species and ultimately aid in their conservation'، he said.