Dare I say legal landings…
“From 1961 to 1973, bluefin tuna represented 45 to 80% of the U.S. western Atlantic catch of large pelagic species. Since 1980, the percentage has dropped to less than 15%, reflecting a combination of the decline in the bluefin tuna population, the impact of catch restrictions, and the increasing harvests of alternative species. Landings for 2005, 2006, and 2007 were 718, 472, and 758 metric tons, respectively.”
“Bluefin stocks remained relatively stable until the 1970s when their value soared as sushi and fresh steaks in international markets, particularly in Japan, which led to a dramatic increase in fishing effort by the U.S. and Japanese longline fleet in the Gulf of Mexico. Spawning stock biomass (SSB) saw a steady decline from the early 1970s to 1992, but after that time it has fluctuated between 18 and 27% of the 1975 level.”
Data: NOAA