Temperature can have a big impact on migration of Bufo marinus as the ani-mal favors warmer weather but tends to desiccate faster under such condi-tions. The threshold temperatures for population growth are estimated as 14 °C and 40 °C, while the optimal temperature range for population growth is estimated as 31 °C to 35 °C (Sutherst et al. 1996). Incorporate a temperature gradient grid into your simulation, where temperatures are cooler to the south and gradually warm for cells further north, as generally happens in Australia. Thus, Desert agents to the north have warmer temperature-state variable val-ues than those further south. Write and incorporate rules using this grid. Have the toads released either gradually or all at once from the middle part of the south border and allow them to migrate off the grid anywhere. Save the temperatures where toads die and migrate, and display two histograms of the numbers of dead and migrated toads versus temperature.