Wildlife Damage Management, Internet Center for


Date of this Version

February 1997


Japanese macaques (Macaca fuscata) are old world monkeys that were introduced to Texas in 1972, and their population has since increased to over 800 individuals. Macaques are considered to be primarily vegetarian but will opportunistically forage on a variety of food items. Therefore, the objective of this study was to determine if macaques impact the nest success of bobwhite quail (Colinus virginianus). In June 1996, 20 artificial ground nests simulating those of bobwhite quail were placed randomly in areas with and without macaques. Nests were checked at 3-day intervals for 24 days and nest success was compared at each time interval between areas with and without Japanese macaques by Z-tests. The monkeys exhibited an immediate detrimental effect on nest success (P = 0.051), destroying or consuming 85% of the nests within the first 3 days and all the nests within 15 days. The combination of all native nest predators on the control area resulted in a compensatory effect regarding nest success (P > 0.106) for days 6 through 12. However, days 15 through 24 resulted in a lower nest success (P = 0.074) on areas with macaques. This study suggests that Japanese macaques could be an important predator of upland game bird nests.