Enter Layout mode. Select the field on your layout. Then clear the "browse" check box in the behavior section of the Inspector's data tab. Now, just on this layout, users will not be able to enter the field while in Browse mode and thus won't be able to modify the Vessel Name.
That is what I did, but was not sure if that was the best way. Thanks for replying.
What I see in your first post:
I tried prohibit modification on the fk_id vessel but that will not let me add any new records to the portal and I tried prohibit on vessel name but that will not allow me to add new vessel names on vessel table. Any help is appreciated.
Is not what I am describing.