Ok, so Christine and Katherine Shipp were teenagers in Byhalia, MS in the 1930's. Byhalia is about 370 miles from the ocean. It's doubtful that they traveled there to ever see a sea lion. So how about this;

This song is about some woman who has a difficult time telling the truth.

She lyin' woman. She drinks coffee (in the morning)- she lie. She drinks tea (an afternoon drink) - she lie. The rooster crows (the sign of a new day) - she's still lying.

That's my take on it.