Terry D. Bills

Toxicity of Potassium Permanganate to Fish and Its Effectiveness for Detoxifying Antimycin

Abstract The 96-h LC50s for potassium permanganate (KMnO4) ranged from 0.750 mg/liter with channel catfish, Ictalurus punctatus, to 3.60 mg/liter with goldfish, Carassius auratus, in laboratory tests. The toxicity of KMnO4 to fish is greatest in water of lower temperatures, in harder water, or in higher pH water. KMnO4 is effective for detoxifying the fish toxicant antimycin in laboratory waters of pH 6.5 to 9.5. The half-life for antimycin exposed to 1.0 mg/liter of KMnO4 ranges from 7 to 11 minutes in the different pH waters at 12 C.

Control of Nuisance Populations of Crayfish with Traps and Toxicants

Abstract Crayfish have long been a nuisance in fishrearing ponds at fish hatcheries. The rusty crayfish (Orconectes rusticus) has displaced endemic species and caused serious declines of aquatic plants in some ponds and lakes in the midwestern USA. We attempted to evaluate the effect of intensive trapping on a crayfish population and to identify a selective chemical control agent and evaluate its effectiveness under field conditions. A crayfish population in a small pond was suppressed but not eliminated by trapping; adults were effectively harvested but efficiency diminished sharply as the population declined. Of 19 chemicals tested as possible control agents for crayfish, a synthetic pyrethroid (Baythroid) was by far the most toxic; 25 μg/L produced a complete kill of crayfish in the pond and was also the most selective for crayfish in laboratory tests.

Effects of Five Diets on Sensitivity of Rainbow Trout to Eleven Chemicals

Abstract This study evaluated the acute toxicity of 11 chemicals to rainbow trout (Salmo gairdneri) fry (average weight 1 g) that had been reared for about 8 weeks on one of five diets: (1) Silver Cup, (2) a purified diet (H440, National Research Council), (3) SD-9 starter diet of the U.S. Fish and Wildlife Service, (4) ground beef liver, and (5) brine shrimp (Artemia). Chemicals tested against the fish were antimycin, carbaryl, chlorine, copper sulfate, sodium cyanide, formalin, malathion, Noxfish, permethrin, salicylanilide 1, and the lampricide 3-trifluoromethyl 4-nitrophenol (TFM). Responses of the fish to the chemicals were consistent in all five groups. No group demonstrated superior resistance to these chemicals. Diet appears to have little influence on the sensitivity of young rainbow trout to chemicals in acute toxicity tests.

Crayfish Control with Traps and Largemouth Bass

Abstract We attempted to control a population of papershell crayfish (Orconectes immunis) in an 11-hectare fish-rearing impoundment in Jackson County, Wisconsin, by using traps and by stocking largemouth bass (Micropterus salmoides). Crayfish were harvested with traps during the summer of 1985, and the pond was stocked with 386 largemouth bass (mean weight, 1.1 kg) in spring 1986. The pond was drained in the fall of 1985 and 1986, and crayfish burrow counts were made to estimate the population. In 1985, we trapped more than 18,000 crayfish, of which 72% were adult males. Trapping had minor effect on the young-of-the-year crayfish. In 1986, the crayfish population was reduced by 98%, predation by largemouth bass being the probable major cause of the reduction.

Comparison of Three Baits for Trapping Crayfish

Abstract In late summers of 1985 and 1986, the efficacies of two commercially manufactured crayfish baits (one each in block and pelleted form) and dead fish as attractants for trapping the mud crayfish Orconectes immunis were assessed in a small Wisconsin lake (area, 5.7 hectares; maximum depth, 6 m). Five sites on the lake were sampled continuously for a 30-d period each year, and each site was fished with three traps. Total harvest of crayfish was 3,949 in 1985 and 2,226 in 1986. Traps with pelleted bait (Crawfish Bait Jumbo) caught more than the others by a 3-to-1 margin in 1985 and by a 2-to-1 margin in 1986. The commercially prepared baits were easier to handle, lacked a putrid odor, required less labor and no refrigeration, and were more readily available than fish carcasses.

Efficacy and Toxicity of Formalin Solutions Containing Paraformaldehyde for Fish and Egg Treatments

Abstract Formalin used for fish and egg treatments at hatcheries often develops a white precipitate called paraformaldehyde when stored at low temperatures. This presents a problem for hatchery managers because most of the literature and treatment procedures claim that formalin containing paraformaldehyde is more toxic than pure formalin and is not safe for fish or egg treatments. Acute toxicity tests with rainbow trout (Oncorhynchus mykiss) and channel catfish (Ictalurus punctatus) showed that the toxicity of formalin solutions containing a moderate amount of fine paraformaldehyde was similar to that of pure formalin. In efficacy tests on fish eggs, the bottom fraction of a formalin solution containing paraformaldehyde and a sample from the clear top fraction were equally effective in controlling fungal infection on rainbow trout eggs and caused no treatment-related mortality. Chemical assays found on average a 3% difference in formaldehyde concentration between top and bottom fractions of a formalin sol...

Factors Affecting the Efficiency of Clinoptilolite for Removing Ammonia form Water

Abstract Clinoptilolite, a natural zeolite, is efficient for removing ammonia from water. This study was done to evaluate its efficiency for removing ammonia under various conditions of water hardness, pH, and temperature, and different granule sizes. Ammonia removal efficiency was unaffected by variations in temperature, but decreased in hard waters, in waters of low and high pH, and with size of granule. Efficiency was optimum in water of 44 mg/L or less total hardness, near neutral pH, and for granules of 20 x 30 mesh size. Adsorptive capacity ranged from 3.42 to 9.12 mg of ammonia per gram of Clinoptilolite.

Sensitivity of Four Species of Carp to Selected Fish Toxicants

Abstract Methods may be needed for controlling the four species of exotic carps now in the United States—common carp (Cyprinus carpio), grass carp (Ctenopharyngodon idella), bighead carp (Aristichthyes nobilis), and silver carp (Hypopthalmichthyes molitrix). We determined the toxicity of four registered or candidate fish toxicants to the carps and delineated the toxicity of GD-174 (2-[digeranylamino]-ethanol) to the four species under various conditions of temperature, water hardness, and pH. The 96-hour LC 50s ranged from 0.570 to 1.00 ppb for antimycin, 1.5 to 9.35 ppb for Salicylanilide I, 0.05 to 0.08 ppm for Noxfish, and 0.05 to 0.55 ppm for GD-174. Toxicity of GD-174 to the four species was little affected by variations in water temperature and water hardness, but was increased at higher pHs. All of the test compounds were toxic to the four species; GD-174 was more toxic to common carp than to the others.

Removal of Toxic Chemicals from Water with Activated Carbon

Abstract Activated carbon was effective in removing fish toxicants and anesthetics from water solutions. Its capacity to adsorb 3-trifluoromethyl-4-nitrophenol (TFM), antimycin, Noxfish(R) (5% rotenone), Dibrom(R), juglone, MS-222, and benzocaine ranged from 0.1 to 64 mg per gram of carbon. The adsorptive capacity (end point considered as a significant discharge) of activated carbon for removal of TFM was determined at column depths of 15, 30, and 60 cm; temperatures of 7, 12, 17, and 22 C; pHs of 6.5, 7.5, 8.5, and 9.5; and flow rates of 50, 78, 100, 200, and 940 ml/min. Adsorptive capacity increased when the contact time was increased by reducing the flow rate or increasing the column depth. The adsorptive capacity was not significantly influenced by temperature but was substantially higher at pH 6.5 than at the other pHs tested. A practical and efficient filter for purifying chemically treated water was developed.

Chemical Control of Fish and Fish Eggs in the Garrison Diversion Unit, North Dakota

Abstract The Garrison Diversion Unit involves the proposed transfer of Missouri River water to a large part of eastern North Dakota for agricultural and industrial uses. Some of the water would flow into Canada through the Red River of the North. Canadian officials are concerned that some nonindigenous species might be introduced to their waters; namely, gizzard shad (Dorosoma cepedianum), rainbow smelt (Osmerus mordax), common carp (Cyprinus carpio), and Utah chub (Gila atraria). We investigated toxicants that might be used to augment other barriers that have been proposed. Chemicals tested against fish eggs and larvae were rotenone, potassium permanganate, chlorine, acrolein, cyanide, fluoride, ammonia, and nitrite. Eggs were generally more resistant than larvae. Only three of the toxicants demonstrated potential to control both eggs and larvae of the species of concern. Rotenone was the most toxic, followed by chlorine and potassium permanganate. Effective exposures required 6-24 hours at concentration...