Accordingly, whale stocks plummeted and by 1968, for example, the blue whale population was only one percent of its level in 1938.
(whale stocks; plummeted; ) (the blue whale population; was; only one percent of its level in 1938; T:by 1968)
whale stocks the blue whale population
plummeted was
only one percent of its level in 1938 T:by 1968