Lots of swimming

Here we have another strip from Jim Toomey's Sherman's Lagoon from last July. In this one we have another potential clue as to the whereabouts of Sherman's Lagoon.  It is apparently 8,681 miles away from The Gulf of Mexico.  The fastest route from Sherman's Lagoon to the Gulf of Mexico would be a "straight line" Great Circle route... unfortunately there aren't any 8,681-mile-long "straight line" Great Circle routes to the Gulf of Mexico that originate in any oceans.  If they don't take a straight-line route then Sherman's Lagoon is still unlikely to be in the Atlantic Ocean since the Gulf of Mexico can be reached from almost any part of the Atlantic Ocean in less than 8,681 miles. Most geographical candidates for being 8,681 miles away from The Gulf of Mexico lie in the West Pacific or the Indian Ocean side of South Africa.  However, the very next day in this story arc the team arrives at the "West Entrance" of the Panama Canal in order to arrive at the Gulf of Mexico via the Caribbean Sea (even though the entrances to the Panama Canal are actually mostly north and south of each other):

So that means that the environs around New Zealand are actually a prime candidate for the location of Sherman's Lagoon.

There have been clues like this before as to the location of Sherman's Lagoon, but they've all come to naught.