Mike Vosburgh
EFFECTS OF NITROGEN, PHOSPHORUS AND THE FUNGICIDE, AZOXYSTROBIN, ADDITIONS ON LARVAL AND POST-METAMORPHIC FITNESS OF AMERICAN TOADS (ANAXYRUS AMERICANUS)
Date: Friday, August 23, 2024
Time: 2:15 PM CST
Location: Quinlan Life Science Building, Room 316
Zoom: https://luc.zoom.us/j/87447605626?pwd=aFX24tKTFluTrg9boHTkxge46pgaIe.1
Abstract
Vast areas of land have been modified by humans for urban development and agriculture. In the Midwestern United States, an estimated 99% of native grasslands have been replaced by agriculture and urban development. Such alternations have replaced native habitat, redefined hydrology and introduced a wide array of chemicals into aquatic ecosystems. Modern agricultural practices utilize fertilizers and pesticides to maximize crop production. These chemicals frequently make it into surrounding waters, potentially effecting aquatic ecosystems. One group of animals thought to be susceptible to agricultural contaminants are amphibians. Amphibians are vulnerable to pollution due, in part, to their permeable skin and biphasic life history. Global amphibian declines are well documented with over 40% of populations either in decline or facing extinction. To evaluate the short-term and long-term (legacy) effects of agricultural chemicals on amphibians, we utilized aquatic and terrestrial mesocosms and exposed American toads to three common contaminants (nitrogen, phosphorus, azoxystrobin) in a fully crossed multi-factorial experimental design. We found that high inputs of nitrogen and phosphorus decreased time to metamorphosis and increased size at metamorphosis. Azoxystrobin exposure had no effect on the metamorphic endpoint metrics. Toad mortality was very high (97%) in our terrestrial mesocosms across all treatments. We recommend further study into the short-term and long-term effects of chemicals and their potential interactions with environmental conditions.
EFFECTS OF NITROGEN, PHOSPHORUS AND THE FUNGICIDE, AZOXYSTROBIN, ADDITIONS ON LARVAL AND POST-METAMORPHIC FITNESS OF AMERICAN TOADS (ANAXYRUS AMERICANUS)
Date: Friday, August 23, 2024
Time: 2:15 PM CST
Location: Quinlan Life Science Building, Room 316
Zoom: https://luc.zoom.us/j/87447605626?pwd=aFX24tKTFluTrg9boHTkxge46pgaIe.1
Abstract
Vast areas of land have been modified by humans for urban development and agriculture. In the Midwestern United States, an estimated 99% of native grasslands have been replaced by agriculture and urban development. Such alternations have replaced native habitat, redefined hydrology and introduced a wide array of chemicals into aquatic ecosystems. Modern agricultural practices utilize fertilizers and pesticides to maximize crop production. These chemicals frequently make it into surrounding waters, potentially effecting aquatic ecosystems. One group of animals thought to be susceptible to agricultural contaminants are amphibians. Amphibians are vulnerable to pollution due, in part, to their permeable skin and biphasic life history. Global amphibian declines are well documented with over 40% of populations either in decline or facing extinction. To evaluate the short-term and long-term (legacy) effects of agricultural chemicals on amphibians, we utilized aquatic and terrestrial mesocosms and exposed American toads to three common contaminants (nitrogen, phosphorus, azoxystrobin) in a fully crossed multi-factorial experimental design. We found that high inputs of nitrogen and phosphorus decreased time to metamorphosis and increased size at metamorphosis. Azoxystrobin exposure had no effect on the metamorphic endpoint metrics. Toad mortality was very high (97%) in our terrestrial mesocosms across all treatments. We recommend further study into the short-term and long-term effects of chemicals and their potential interactions with environmental conditions.