Last Trip Return Rate Influence Patch Choice Decisions of Small-Scale Shrimp Trawlers: Optimal Foraging in Sao Francisco, Coastal Brazil

Studies using Optimal Foraging Theory to understand human behavior have stated that daily variation in patch profitability could explain mismatches between theoretical predictions and actual behavior. In this paper, we tested whether the return rate of the last fishing trip could predict fishers' choices to return or choose a different fishing ground for their next trip. We collected data on fishing trips using interviews and direct observation of fishers' activities at the main landing point in So Francisco, a small-scale shrimp fishing community on Brazil's southern coast. We found that fishers returned more often to fishing grounds where the return rate of the previous fishing trip was above the average gross return of the environment. Daily variations in patch quality accounted for fishers' decisions, but other factors may also influence the observed behavior, such as scale of analysis, information exchange, environmental conditions, and economic variables.