Final 1999 BLOY Report

Tetreau, Michael

To examine the consequences of increased human recreation on beaches in Kenai Fjords National Park, Alaska, we studied productivity and behavioral effects of human disturbance upon nesting Black Oystercatchers (Haematopus bachmani), residing in Aialik Bay during the summer of 1999. We focused on human interaction near the nesting areas. Initial inventories throughout Aialik Bay were performed to locate nesting sites and identify bird species. 21 pairs of oystercatchers were recorded in the bay, of which, 15 made nesting attempts. The estimated productivity of Aialik Bay was 8.33% of the chicks fledged. Clutch size averaged 2.18 eggs per nest. The estimated hatching success was 19.44%. For the behavioral study, observations were performed for three similarly-proportioned time periods: pre-disturbance, disturbance, and post-disturbance. We based the study upon random and intermittent human disturbance, not constant, perpetual, or predator disturbances. The data quantifies bird behavior and human behavior to determine any correlation between the two. At the 90% confidence interval statistics show that the birds spend less time foraging when humans occupy their habitat. They also made more frequent trips to foraging areas. Less foraging and more flying may adversely affect adults and chicks. The human disturbance consisted of two kayakers that would land on a select beach where nesting oystercatchers resided. The kayakers always maintained a 100m buffer distance from the nest, so we didn t purposely cause a nest failure. They usually camped between 100 and 150m away from the nest, keeping any unusual camping behaviors to a minimum. The birds usually displayed heightened awareness or agitation mildly associated with kayakers arriving at or departing the beach. We suggest that the impacts of human interaction be regulated accordingly with both temporal and spatial restrictions on human use.