PARENT SESSION
Contributed Oral Session 156: Grassland Resource Allocation, Dispersal, and Pollination
Friday, August 12, 8:00 AM - 11:30 AM, Meeting Room 516 C, Level 5, Palais des congrès de Montréal

Impact of isolation on pollination of tall-grass prairie plants.

Robson, Diana^*,1, ¹ The Manitoba Museum, Winnipeg, MB, Canada

ABSTRACT- This study compares insect pollination activity on small isolated and larger contiguous Tall-grass prairies to better understand the impact of habitat isolation on this process. Floral abundance and pollinator activity was monitored every two weeks for four months in 2004. Total and insect-pollinated plant species richness was lower at the isolated site compared to the contiguous site. The insect species richness and number of visitations of Dipterans were lower and Hymenopterans higher at the isolated site than at the contiguous site. Plants in the Asteraceae were each pollinated by 4-5 different insect species while plants in other families were pollinated by 1-2 species. The isolated site had greater variability in pollinating insect species over the year than the contiguous site. The environmental variables that most influenced insect activity were humidity, wind speed and cloud cover. These results show that insect diversity and pollination activity are different at isolated and contiguous sites, which may affect seed production

Key words: Habitat isolation, Pollination, Insect pollinators, Tall-grass prairie