Complex sentence: However their arguement was flawed as many fisheries in the world, such as in Antarctic waters are virtually untouched but they are remote from the USA and require very large seagoing vessels.In shore fisheries need to be managed carefully to ensure overfishing does not occur.
Split into simpler sentences: However their arguement was somewhat flawed as many fisheries in the world, such as in Antarctic waters are virtually untouched but they are remote from the USA and require very large seagoing vessels. Inshore fisheries need to be managed carefully to ensure overfishing does not occur.