As soon as they arrived at Santa Katalina, they anchored, and sent their men ashore with some heavy guns. The Spanish garrison was strong, and the fortress well situated, but in a few days they forced it to surrender. They then crossed by a bridge of boats to the lesser island to the north, where they ravaged the plantations for fresh supplies. Having blown up all the fortifications save the castle, they sent the Spanish prisoners aboard the ships. They then chose out 100 trusty men to keep the island for them. They left these on the island, under the command of a Frenchman of the name of Le Sieur Simon. They also left the Spanish slaves behind, to work the plantations, and to grow maize and sweet potatoes for the future victualling of the fleet. Mansvelt then sailed away towards Porto Bello, near which city he put his prisoners ashore. He cruised to the eastward for some weeks, snapping up provision ships and little trading vessels; but he learned that the Governor of Panama, a determined and very gallant soldier, was fitting out an army to encounter him, should he attempt to land. The news may have been false, but it showed the buccaneers that they were known to be upon the coast, and that their raid up "the river of Colla" to "rob and pillage" the little town of Nata, on the Bay of Panama, would be fruitless. The Spanish residents of little towns like Nata buried all their gold and silver, and then fled into the woods when rumours of the pirates came to them. To attack such a town some weeks after the townsfolk had received warning of their intentions would have been worse than useless. Mansvelt, therefore, returned to Santa Katalina to see how the colony had prospered while he had been at sea. He found that Le Sieur Simon had put the harbour "in a very good posture of defence," having built a couple of batteries to command the anchorage. In these he had mounted his cannon upon platforms of plank, with due munitions of cannon-balls and powder. On the little island to the north he had laid out plantations of maize, sweet potatoes, plantains, and tobacco. The first-fruits of these green fields were now ripe, and "sufficient to revictual the whole fleet with provisions and fruits."