Without any agricultural crops or experience eating the food on which the Indians subsisted (ground acorns), the shortage of food at San Diego became extremely critical during the first few months of 1770. They subsisted on some of their cattle (Texas Longhorns), wild geese, fish, and other food exchanged with the Indians for clothing, but the ravages of scurvy continued for there was restricted amounts of food and no understanding of the cause or cure of scurvy then. A small quantity of corn they had planted grew well—only to be eaten by birds. Portolá sent Captain Rivera and a small detachment of about 40 men to the Baja California missions in February to obtain more cattle and a pack-train of supplies. This temporarily eased the drain on San Diego's scant provisions, but within weeks, acute hunger and increased sickness again threatened to force abandonment of the port. Portolá resolved that if no relief ship arrived by 19 March 1770 they would leave the next morning "because there were not enough provisions to wait longer and the men had not come to perish from hunger." At three o'clock in the afternoon on 19 March 1770, as if by a miracle, the sails of the sailing ship "San Antonio" loaded with relief supplies were discernible on the horizon. The settlement of Alta California would continue.