Biota of Chazy Lake: The Legacy of Invasive Species and other Abiotic Stressors

Abstract

Freshwater systems are threatened with poor water quality and invasive species, affecting their overall health. Chazy Lake is an oligotrophic impounded freshwater lake in Clinton County, New York approximately 1,800 acres in size and surrounded by mountains. Invasive species have become an increasing threat to the lake and include Eurasian watermilfoil (Myriophyllum spicatum), Chinese mystery snail (Cipangopaludina chinensis), and northern pike (Esox lucius). Abiotic stressors, such as road salt, are also major concerns. Over the course of four weeks in fall 2022, we surveyed the lake for fish and turtle community composition. At each site, hoop traps (n=2 minnow, n=1 turtle) were set at two reference (South Inlet, Pump station) and two disturbed (Dam, Seine Bay) sites. We created a Survey123 project to remotely georeference sites, curate images, and answer form questions. Water samples were collected to evaluate abiotic factors such as conductivity and pH. The species richness of the fish community was 5 and included 17 individuals including creek chub (Semotilus atromaculatus), pumpkinseed sunfish (Lepomis gibbosus), rock bass (Ambloplites rupestris), brook stickleback (Culaea inconstans), and yellow perch (Perca flavescens). Our hypothesis was not entirely supported as the majority of our fish were caught at the pump station (n=10) and disturbed Seine Bay (n=7) sites. None of the fish surveyed displayed disease phenotypes and no turtles were observed. Abiotic factors were surprising, as high conductivity (512 uS/cm) levels aligned with the Seine Bay, a site adjacent to a major roadway, while other sites averaged (94 uS/cm). Water chemistry revealed similar pH levels across sites 7.28-7.75. Non-profit organizations are addressing these threats with management efforts including lake drawdowns and seasonal watermilfoil removal. Long-term water quality monitoring has afforded residents opportunities to discuss alternatives and ways to minimize use of road salt. The lack of fish and turtles found in Chazy Lake may be just one sign of on-going threats associated with invasive species and pollution.