REDUCING NUISANCE CANADA GOOSE PROBLEMS THROUGH HABITAT MANIPULATION

Urban populations of Canada geese (Branta canadensis) cause considerable problems when large numbers congregate in parks, playing fields, and backyards. In most cases, geese are drawn to these sites to feed on the lawns. I tested whether geese have feeding preferences for different grass species. Captive Canada geese preferred Kentucky bluegrass (Poa pratensis) and disliked tall fescue (Festuca arundinaceae) over colonial bentgrass (Agrostis tenuis cv. Highland), perennial ryegrass (Lolium perenne), and red fescue (Festuca rubra). They refused to eat some other ground covers such as pachysandra (Pachysandra terminalis) and English ivy (Hedera helix). These results suggest that goose numbers at problem sites could be reduced by changing the ground cover. I also compared the characteristics of foraging sites used by geese to other foraging sites that geese avoided. Occupied sites were more open so that geese had clearer visibility and greater ease in taking off and landing. This suggests that goose numbers at problem sites also could be reduced by planting tall trees to make it harder for the geese to fly away, and planting bushes and hedges to obstruct a goose's visibility.

An Investigation of Wild Bee Diversity and Abundance in Plots Managed by The Nature Conservancy in South-Central Nebraska and of Beneficial Arthropods Associated with Native Nebraska Flora

Insect pollination is an essential ecosystem service, and bees are the principal pollinators of wild and cultivated plants. Habitat management and enhancement are a proven way to encourage wild bee populations, providing them with food and nesting resources. I examined bee diversity and abundance in plots managed by The Nature Conservancy near Wood River, NE. The plots were seeded with 2 seed mixes at 2 seeding rates: high diversity mix at the recommended rate, high diversity mix double the recommended rate, Natural Resources Conservation Service (NRCS) conservation planting (CP) 25 mix at one-half the recommended rate, and NRCS CP25 mix at the recommended rate. I measured wild bee abundance and diversity, and established a database of wild bees associated with the plots. I also compared genus richness and abundance among the plots using and aerial net and blue vane traps to collect bees. Significant differences were not observed in genus richness and diversity among the plots; however, plot size and the ability of blue vane traps to draw bees from a long distance may have influenced my results. In 2008, 15 genera and 95 individual bees were collected using an aerial net and in 2009, 32 genera and 6,103 individual bees were collected using blue vane traps. I also studied the beneficial insects associated with native Nebraska flora. Seventeen species of native, perennial flora were established in 3 separate plots located in eastern Nebraska. I transplanted four plants of each species in randomized 0.61 m x 0.61 m squares of a 3.05 m x 9.14 m plot. Arthropods were sampled using a modified leaf blower/vacuum. Insects and other arthropods were identified to family and organized into groups of predators, parasites, pollinators, herbivores, and miscellaneous. Associations between plant species and families of beneficial arthropods (predators, parasites, and pollinators) were made. Pycnanthemum flexuosum Walter attracted significantly more beneficial arthropod families than 7 other species of plants tested. Dalea purpurea Vent and Liatris punctata Hook also attracted significantly fewer beneficial arthropod families than 4 other species of plants tested. In total, 31 predator, 11 parasitic, 4 pollinator, 31 herbivore, and 10 miscellaneous families of arthropods were recorded.