Yes, Boca Chica was definitely North Blyth. Just a short walk from where the ford was across the river where the High Ferry crossing was.
John Wallace explained how Boca Chica got it's name in 1745.
1745 About this time Boca Chica received its outlandish name. Two seamen belonging to the place had served on board a ship-of-war, under Admiral Vernon, at the siege of Carthagena, a sea port in South America, in 1741. The entrance into the harbour was termed Boca Chica (i.e. little mouth), and was defended by several forts, the whole of which were taken by the British forces. Those seamen having returned home in recounting their exploits at the siege so frequently used the words Boca Chica, that one of their companions jocularly gave the name to the place of their residence; the new name took with the public, who at once adopted it, and to this day Boca Chica has continued to be the name of the northern portion of the High Pans. (Wallace)
[Boca Chica existed as a local place name for more than 200 years, right up to the housing clearance of North Blyth circa 1960, it also featured on maps of the area].
When the colliery rows were built in Victorian times one of the rows was called Boca Chica. No doubt the original row was demolished to make way for the new terraces.
The name Boca Chica lives on! A brand new house that is in the process of being built at Cambois, is named Boca Chica.
Philip