Cooperative Fish and Wildlife Research Units Program: Texas
Education, Research and Technical Assistance for Managing Our Natural Resources

ABSTRACT.- Urban ecosystems have become attractive to several species of raptors, especially those that typically use smaller prey, such as the Mississippi Kite (Ictinia mississippiensis). To better understand the niche filled by urban nesting Mississippi Kites, we collected 269 hrs of direct observation at 10 kite nests during the breeding seasons of 2010 and 2011. We assessed prey delivery rates and prey use within and between years, evaluated the influences of nestling age, time of day, and local atmospheric conditions on delivery rates, and examined provisioning rates by male and female kites. A 62% decrease in the prey delivery rate from 2010 to 2011 was attributed to extreme heat and drought during the 2011 breeding season. However, biomass of identified deliveries increased 182% in 2011 due to an increase in avian prey from 1% to 16% of identified deliveries. We found weather conditions influenced the type of prey delivered, but that nestling age and time of day were better predictors of a prey delivery being made. On average, females delivered significantly more prey items than males, but inconsistencies among nests suggest additional factors may be influencing parental effort. Our results indicate that Mississippi Kites will exhibit prey switching under adverse conditions, the ability of urban landscapes to buffer against environmental conditions has limits, and that gender-specific partitioning of foraging efforts may not provide the advantages to kites that are observed in other raptor species.