Abstract:
Harmful cyanobacterial blooms (HCBs) can lead to water quality problems and adverse health effects in humans, livestock, wildlife, and pets. The Wyoming Department of Environmental Quality (WY DEQ), Wyoming Department of Health, and the Wyoming Livestock Board have identified many waterbodies across Wyoming that have experienced HCBs recently, including 44 water bodies with HCB advisories and 9 with toxin advisories as of late-September 2022. Previous research indicates that despite an increase in the number of bloom advisories in recent years, chlorophyll concentrations, an indicator of bloom presence and severity, has been relatively constant across Wyoming in the past several decades. These results, suggest that the uptick in advisories is a result of increased awareness rather than a widespread increase in nutrient pollution. In the last two years, WDEQ has increased the frequency of monitoring for toxins to better understand which blooms pose the greatest risk to people and animals. However, we still lack understanding of the relationship between blooms and associated toxin levels, the most effective ways to monitor for cyanotoxins, and the potential linkages between nutrient pollution and toxin production. In this project, we propose to address those knowledge gaps by: 1) examining cyanobacterial blooms and cyanotoxin levels across a gradient of lakes to determine when blooms are likely to be most toxic to humans, livestock, pets, and wildlife, 2) comparing field methods, sampling designs, and laboratory methods for measuring cyanotoxins, and 3) conducting a detailed evaluation of the timing of nutrient loading, bloom formation, and toxin production in two focal waterbodies. This research will contribute to ongoing efforts by state agencies to monitor cyanotoxins and evaluate when HCBs are most hazardous to the health of humans and animals. Our project will provide training for one graduate student and several undergraduate field and laboratory technicians at the University of Wyoming.