Optimal Foraging

Students work in groups of three, with each member assigned a specific role. One student forages by collecting prey items, one records data on a collection sheet, and one operates the stopwatch to measure foraging time. This division ensures accurate data collection and allows all students to participate in different aspects of the experiment.

You need four five-gallon buckets labeled A, B, C, and Average, each filled with 15 to 30 pounds of rice. Mix pinto beans into each bucket to represent different prey densities: six beans for low density (bucket A), 16 beans for medium density (bucket B), 26 beans for high density (bucket C), and 16 beans for average density. Place an empty cup next to each bucket for collecting prey.

Place buckets A and Average at the start of the foraging area five paces apart. Walk 25 paces away and place bucket C. Then walk 10 paces right or left of C and place bucket B. The average bucket always starts at the beginning, though bucket arrangement, distances, and prey numbers can be varied for different trials or convenience.

Pinto beans mixed into rice represent prey items, with different quantities simulating varying prey densities. Six beans represent low prey density, 16 beans represent medium prey density, and 26 beans represent high prey density. The average bucket with 16 beans provides a baseline for comparison, allowing students to observe how foraging efficiency changes across different resource availability levels.

An open field is ideal for this activity because it provides adequate space for bucket placement and foraging movement. However, a hallway can suffice if another location is not available. The space must accommodate the bucket arrangement and allow students to move between patches while the stopwatch measures foraging time.

Remixing pinto beans into the rice after each forager ensures consistent prey distribution for subsequent trials. This maintains uniform prey density within each bucket and prevents depletion of beans in specific areas, ensuring that each student forager encounters the same prey availability conditions and allowing for valid comparisons across multiple trials.

The activity offers flexibility in several ways: bucket arrangement, distances between patches, and prey item numbers can all be varied. Students can explore how different spatial configurations or prey densities affect foraging decisions. These modifications allow investigation of how environmental factors influence optimal foraging behavior and decision-making strategies.