NEST VISITATION BY HUMANS DOES NOT INCREASE PREDATION ON CHESTNUT-COLLARED LONGSPUR EGGS AND YOUNG

The influence of nest visitation by humans on predation on Chestnut-co llared Longspur (Calcarius ornatus) eggs and nestlings was examined. I n contrast to previous correlational studies of this nature, an experi ment was designed in which the level of observer nest disturbance was randomly determined (a priori). Only nests surviving at least seven da ys of incubation were used in the analysis to control for bias introdu ced when nests are found at different times during the nesting cycle. Visitation did not significantly increase predation (P = 0.50) and the re was a trend toward decreased predation with increased visitation.