Easton's Bible Dictionary (1897)
Black-white, a stream on the borders of Asher, probably the modern Nahr Zerka, i.e., the “crocodile brook,” or “blue river”, which rises in the Carmel range and enters the Mediterranean a little to the north of Caesarea (Josh. 19:26). Crocodiles are still found in the Zerka. Thomson suspects “that long ages ago some Egyptians, accustomed to worship this ugly creature, settled here (viz., at Caesarea), and brought their gods with them.
Once here they would not easily be exterminated” (The Land and the Book).
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
SHI'HOR-LIB'NATH (black-white), a landmark of Asher. Josh 19:26. The term is usually supposed to refer to a river which formed the extreme point of the frontier toward the south, and must have included Dor. Probably the Zerka, or "Blue River," which runs into the Mediterranean south of Dor; but Conder suggests its identity with Wady Shagkur.