Navadyaksha (The Chief Naval Commander of Mauryan Empire)

The Mauryan Empire Map
Navadyaksha is the Chief Commander of Mauryan Navy
It is interesting to note that the Mauryans never fought any naval battle, but all three Great Emperors of Mauryan Dynasty i.e. Chandragupta, Bindusara and Ashoka maintained a strong navy. The prime reason is to protect traders from the pirates (himsrika).

Their Naval Commander was referred as Navadyaksha. The terms Navadhyaksha literally translates as the Chief Controller of Shipping. His responsibilities include supervising maritime safety and rescue operations, running shipping services, hiring ships and boats with or without crew, organizing fer­ries, controlling the movement of foreign merchants, collecting taxes such as customs duty and ferry charges and ensuring security by keeping a watch over undesirable persons using the ferries.

The Navadyaksha is assited by the Pattanadhyaksha (Chief Controller of Ports and Harbours), Manadhyaksha (Chief Time Keeper) and other officers in the Mauryan administration. In the case of precious metals and gemstones, he need to discuss the matter with Suvarnadhyaksha (Chief Controller of Mining and Metallurgy).

Source: Kautilya Arthashastra