He arrived at the city on September 4, 1578, and he ruled it in an interim way, in service to Menéndez de Márquez.
According to an account of the achievements of Quirós, while he worked as lieutenant governor, he signed peace treaties with the leaders of the indigenous people of the city and he tried to create a "pueblo formado" (formed town) there.
To do this, he was asked to negotiate with the chief Cazacolo and convince four of the most important Guales to visit Saint Augustine, the Florida capital.
In Saint Augustine, Quirós would make them prisoners and give them gifts and then be asked to surrender the Frenchman.
In addition, Quirós was asked to find a half dozen Native American women in Saint Augustine who gathered oysters.