2013 study Fukushima daiichi radiation in tuna?

Full study @link
http://blogs-images.forbes.com/monteburke/files/2013/02/EST_2013_DJM.pdf
"We collected 50 samples of PBFT in 2012 and measured muscle tissue for 134Cs and 137Cs to determine if the acquisition of radiocesium by migrating PBFT persisted into the summer of 2012, more than a year after the Fukushima disaster. Radiocesium levels were compared to concentrations of another γ-emitting radionuclide, the naturally occurring 40K, to provide context for observed radiocesium concentrations. For comparison, we also collected 5 samples of yellowfin tuna (Thunnus albacares) in 2012, which are known from electronic tagging studies to be residents of the CCLME and do not make migrations from the western Pacific Ocean.5,16 We used small PBFT, known to be migrants from Japan, to test whether all migrants would demonstrate a measurable radiocesium signal from Fukushima. We examined the radiocesium levels in older fish to determine if residents and migrants could be discerned via the absence of 134Cs (due to excretion during a year or more in CCLME waters) or presence of 134Cs (due to recent migration from Japan). Finally, we use ratios of 134Cs:137Cs to estimate time of departure from Japan in recently migrated PBFT."

http://blogs-images.forbes.com/monteburke/files/2013/02/EST_2013_DJM.pdf