Oral Abstract Details

Author(s):
John J DeLuca and Kathryn E Sieving

Affiliation:
Department of Wildlife Ecology and Conservation, University of Florida

Presentation Type:
Oral

Topic Area:
Evaluating changes to ecosystem goods and services along urban-rural gradients

Abstract Text:
Conservation biologists recognize that modern farmlands represent critically important, but largely unsuitable, land area needed for protection of global biodiversity resources. So much land is under cultivation and close to increasingly limited natural areas that conservation cannot succeed without increasing the overall biodiversity holding capacity of farmlands. We evaluated the responses of wildlife populations [Eastern Bluebird (Sialia sialis)] utilizing both natural and cultivated lands in the urban-wildland gradient of North-central Florida to reveal issues influencing whether conservationists can – under the best conditions (sustainably managed farmlands) – responsibly promote farmlands as wildlife habitat. In 2007, we tested for the effects of land management (reduced-impact farms [e.g., organic], conventional farms, and natural control areas) on the reproductive success and breeding behavior of bluebirds using standardized nest boxes we provided. Farmland bluebirds began breeding earlier and produced more clutches and eggs than bluebirds in natural areas yet produced the same total number of fledglings over the breeding season. In 2008, we compared arthropod prey availability in addition to land management influences on bluebird reproduction. Prey was more bountiful but more unstable on farms; higher mean prey biomass was correlated with early nesting but higher variation in prey biomass was correlated with lower hatchling production in first broods. In comparison to natural areas, farmlands varied from marginally suboptimal (2007, a dry year) to surprisingly poor habitat for breeding bluebirds in a wet year (2008). Because bluebirds and other native insectivorous bird species are significant consumers of agricultural pests (lepidotera, orthoptera), the ability of farmland systems to support viable wildlife populations conveying critical ecosystem services is a larger sustainability issue - not just a biodiversity conservation issue. Future research and monitoring of reproduction and health of wildlife populations on farmlands is needed to determine the full potential for food-production lands to support sustainable human-dominated ecosystems.