By Atuna.com
A team of researchers from the Spanish Institute of Oceanography (IEO) and the University of Sassari in Italy are studying the biology of Mediterranean tuna through the analysis of their parasites.
The parasites act as natural markers, evolving at the same time as their hosts, so they can be used to determine the ecology and migration patterns of tuna. The team most recently analyzed some parasites found in tuna that are believed to have migrated between the tropical areas of the Atlantic Ocean and the Mediterranean Sea. Their research is ongoing and they hope it will eventually serve as useful data for fisheries management.
Parasites often need very specific environmental conditions to breed and this affects their host selection. In some cases, parasites require several hosts to develop properly, so their survival can depend on a set of species.
Given the highly migratory nature of tuna, which swim across oceans, the habitat changes may affect the presence of the invading organism.
The scientists say natural markers, such as parasites, have some advantages over the use of artificial marking. The biomarkers, for instance, allow deep-sea species to be studied without the problems of decompression. They also enable routine analysis of samples from scientific and commercial surveys, which reduces costs, because the fish do not have to be recaptured.
However, the scientists also say their studies are limited by the lack of information on the parasitic fauna of tuna. As a result, it’s difficult to make relevant and reliable conclusions.