Degree Name

Master of Science (MS)

Semester of Degree Completion


Thesis Director

Eric K. Bollinger


I studied the effects of nest box visibility and clustering on the rate of intraspecific brood parasitism (IBP) in Wood Ducks (Aix sponsa) at Lake Shelbyville Fish and Wildlife Area in Moultrie County, IL from 2 March 1992 to 22 June 1992. Sixty-eight percent of the nest boxes sampled were used and 33% of the nests were destroyed by predators. Mean clutch sizes of unparasitized (x = 9.2) and parasitized (x = 15.2) nests were significantly different. The parasitism rate in Wood Duck nests was 54%. More visible boxes had a tendency to be parasitized at a higher rate than less visible boxes. However, nest boxes located closer to other boxes did not have higher rates of IBP. In fact, boxes that were further apart had higher (but statistically non-significant) rates of IBP than nest boxes found closer together. Unparasitized nests had a higher hatchability (91%) than parasitized nests (73%). A clutch size criterion of ≥12 eggs (to indicate a parasitized nest) gave the best estimate of the percentage of nests parasitized (49%, a 5% underestimate).