“Gilead.” There is no tribe of Gilead, so this may be a circumlocution for the tribe of Gad. The tribe of Dan was located in the Transjordan, east of the Jordan River.
“ships.” The original allotment of Dan had access to the Mediterranean Sea.
“harbors.” The Hebrew word is only used here in the Bible, and it has the connotation of being a place that is protected from the force of the ocean and used as a landing place for boats. It could be translated “bay,” since it is naturally occurring and not man-made. Asher was in north Israel, and the Mediterranean coast of Asher had many more bays and jetties than did the lower coast of Israel.