Aquatic Plant Surveillance on the Niagara River: Ground truthing a Predictive Model Sample Selection
The Niagara River is a high-priority waterway due to its immense ecological, economic, and recreational value, in addition to its role in connecting New York’s two Great Lakes. The areas of the upper river around Grand Island have been determined as significant fish habitat, particularly as native muskellunge spawning areas, and in 2022, invasive Hydrilla verticillata was found to have expanded into multiple sites within the upper Niagara River. Additionally, a full-scale SAV mapping of the Niagara River has not occurred since the early 20th century. With these considerations in mind, it is necessary to conduct a large-scale aquatic plant surveillance project in the Niagara River to determine extent of hydrilla and other aquatic invasive plants, as well as native vegetation. This primary objective of this project was to deploy the method outlined in previous seasons of the Invasive Aquatic Plant Surveillance in New York Great Lakes Ports project alongside the standard, non-randomized systematic sampling method that is used throughout New York in another high-priority system with the primary goal being to ground truth the predictive, high-efficiency method. Under the NYS WRI Aquatic Invasive Species Program, the standard method is to survey pre-determined points every 50 meters in areas less than 9 meters deep with no randomization; all points generated are scheduled to be visited during the surveillance period. The WRI team planned to conduct rake toss samples at all locations, and use the data collected to compare and analyze the differences in distribution and abundance with what was observed at all locations versus if they had only sampled at predicted locations.