Point to Point Distances around coastlines

Discussion created by sjpittman on Aug 24, 2012
Latest reply on Sep 5, 2012 by simply_gis
I am trying to calculate point to point distances for 125 points scattered in the sea around a Caribbean island.  Hawth's point to point tool will provide straight line distances but these paths in many cases would go over land.  I am interested in calculating the distances between points for pathways of fish that must stay in the sea and not cross over land (i.e. shortest distance but sometimes around headlands and islands etc. 
Any ideas on how I can do that?  Thanks