Laboratory work for Ningaloo Outlook, our strategic marine research partnership with CSIRO, has commenced. During tagging of turtles, reef sharks and whale sharks, small samples were collected by CSIRO scientists from nearly 60 animals.  The samples will reveal a great deal about the animals and are used in a number of fascinating ways to collect important data which can help scientists identify the diet, population diversity and habitat of the species. 

DNA analysis is undertaken and gives scientists an idea of the genetic variation of a species in a specific area. This data can also be used to determine if a population is recovering from a small number of individuals, and can determine how many members of a certain species in an area are related and how closely. This information is extremely valuable for developing conservation management plans for threatened species, like whale sharks.

To identify the habitat and the diet of an animal, researchers undertake stable isotope analysis of the samples to measure the ratio of heavy-to-light isotopes of a particular element (such as carbon). This is possible because plants take elements from the environment in different ways and this influences the stable isotope ratios of the elements in the plant. These ratios remain constant when the plant is eaten and digested by an animal, giving the animal’s tissue a very similar stable isotope ratio. Scientists are then able to trace these ratios through the food chain to identify what an animal has been eating and where it has been eating it. This is important developing conservation plans to identify and protect critical sources of food and habitat.

To perform stable isotope analysis on animal tissue, the samples are cleaned and dried, then sent to a specialist lab at the University of Western Australia where they will be passed through a mass spectrometer, a special instrument that measures isotope ratios. 

After collecting samples from nearly 60 animals during the first round of tagging, researchers at the CSIRO’s marine research laboratory in Perth and the University of Western Australia’s mass spectrometer will be kept busy for some time to come.