fisheries.noaa.gov

R5xZ8 TIL that lobsters can discard their limbs in a process called "reflex amputation": new limbs then grow to replace them.
oR1YY TIL Sperm Whales consume roughly twice as much seafood as all of humanity combined per year. With Sperm Whales (the largest toothed predators) consuming roughly 300 million tonnes per year and humans consuming about 160 million tonnes. (Further sources in comments)
78geZ TIL that the smallest fish in the world, the Tiny Goby, rarely grows longer than half an inch. Despite this, they are so abundant that they can support an entire fishery