Rats in oil palm plantations in Central Kalimantan can cause significant damage to crops. A study found that the house rat species, Rattus rattus diardii, is the main culprit, with populations ranging from 185 to 718 rats per hectare. The more rats there were, the more damage they caused to fruit bunches, leading to potential losses of up to USD 779.64 per hectare per year. Efforts to control rats using barn owls were not as effective as hoped, suggesting a need for a combined approach of baiting and biological control.