Parallel animal migration models of bison and elk in Northern Yellowstone National Park

In landscape ecology, computer models are developed to simulate the migration of animal groups as they exist in nature. Typically, these models are sequential and the animal groups move and forage in sequence. In this work, we discuss the parallelization of the NOYELP (Northern YELlowstone national Park) model on a 32-processor Thinking Machines CM-5. NOYELP is a spatially-explicit individual- based model that simulates the search, movement and foraging activities of groups of animals across the northern portion of Yellowstone National Park. NOYELP is primarily used to study the effects of fire scale and pattern on the winter foraging dynamics and survival of free-ranging bison and elk groups. Among four versions of a parallelized NOYELP model (referred to as PNOYELP), the version (AM) based on arithmetic means of shared variables is shown to provide daily energy gain statis- tics closest to the sequential NOYELP model with reasonable speed improvements (ranging from 2.8 to 6.7) over the sequential model executing on a Sun SPARCstation10.