In order to intercept this year's bluefin class, we headed to the Cigar seamount 50 miles off of Virginia Beach. By trolling No. 1 Clark spoons behind No. 1 planers or 5-ounce inline sinkers, we were able to provide Dr. Graves with 17 baby bluefin for his research. We also caught dozens of baby blackfin, skipjack, and albacore - most measuring between 10 and 14 inches long.
Not only will the scientist at VIMS analyze the DNA of these small bluefin, but other researchers will look at isotopes in the fish's ear-bone and contaminants in the tuna's tissue to further nail-down the natal origin of the fish. Once signatures that identify the birth place of these fish are identified, scientists can look for the same markers in larger tuna to determine the number of Western Atlantic bluefin that are caught in the Eastern Atlantic and vice versa.
This information will be used to help fisheries managers understand how these fish travel and set regulations that will protect their highly threatened populations.
"There is unbelievable amount of overfishing occurring in the Mediterranean Sea and eastern Atlantic," Grave says, "These data allow ICCAT (International Commission for the Conservation of Atlantic Tunas) to hammer on the East to put realistic limits on their catches."