Del Wayne R. Nimmo | USGS Science

USGS1990

Three studies using Ceriodaphnia to detect nonpoint sources of metals from mine drainage

Since its introduction, Ceriodaphnia dubia , a small planktonic daphnid, has been widely used for biomonitoring point source discharges. This species was also used to determine nonpoint sources of metals and related contaminants in three trout streams in the west where mining activities have been widespread. Along Chalk Creek, Colo., specific tailings (and impacted tributaries) were sources of metals toxic to fish using the water in a hatchery. At stations below extensive mine tailings in the upper Clark Fork River, Mont., drainage was acutely and chronically toxic to daphnids and paralleled reduced or nonexistent populations of trout. In Whitewood Creek, S. Dak., reduced toxicity below a gold mine portended that fish could live in the stream segment previously impaired by the mine. Toxicity downstream revealed a previously unknown nonpoint source of chromium.

Research Journal of the Water Pollution Control Fe↗

USGS1989

Comparison of on-site and laboratory toxicity tests: derivation of site-specific criteria for un-ionized ammonia in a Colorado transitional stream

Acute tests with fathead minnows ( Pimephales prornelas Rafinesque), johnny darters ( Etheostoma nigrum Rafinesque), white suckers ( Catostomus commersoni Lacépède) and acute and chronic tests with Ceriodaphnia dubia were conducted to evaluate whether characteristics of the St. Vrain River in Colorado would ameliorate or enhance toxicity of un-ionized ammonia compared to laboratory (well) water and LC50 values found in the literature. Concurrently, tests were conducted on dilutions of Longmont, Colorado, wastewater to evaluate its toxicity in differing ammonia concentrations. Tests were conducted at two temperatures (approximately 6 and 20°C) to simulate seasonal differences. LC50s for fishes in the St. Vrain River water were similar to LC50s in laboratory water, indicating there was no site water effect. LC50s derived for fishes tested in warm conditions were within a factor of about two or three of literature values. However, the constituents in or characteristics of the wastewater appeared to enhance ammonia toxicity. Literature values (LC50s) for resident aquatic organisms and the new LC50 value for johnny darters tested on-site were used to derive site-specific criteria for un-ionized ammonia. Greater sensitivities of species to ammonia at cold versus warm temperatures suggests that colder, low-flow conditions may be a critical period for warm-water aquatic communities with regard to ammonia toxicity.

Colorado↗