Illegal shipping is a small problem (~$100M?)

Illegal fishing is not - $10 - $23B annually in cost (2009)[1], destroys fish stocks, and contributes to slavery and human trafficking.[2]

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2646833/

[2] https://fas.org/irp/nic/fishing.pdf