Dennis T. Burton

A comparison of the avoidance responses of individual and schooling juvenile Atlantic menhaden, brevoortia tyrannus subjected to simultaneous chlorine and ΔT conditions

The objectives of this study were to determine and compare the avoidance responses of individual and groups of Atlantic menhaden, Brevoortia tyrannus, exposed to simultaneous elevated temperature (0, 2, 4, and 6 degrees C) and total residual chlorine (TRC) (0.00, 0.05, 0.10, and 0.15 mg/l) conditions. An unbalanced three-factor factorial design was used to develop predictive avoidance models with this species at a test temperature of 25 degrees C. Fish tested in groups elicited the following avoidance responses: (1) a high avoidance response occurred at 0.10 and 0.15 mg/l TRC regardless of delta T; (2) avoidance increased with increasing delta T values at 0.00 mg/l TRC; and (3) TRC was the most important factor influencing avoidance. Atlantic menhaden tested individually demonstrated the following responses: (1) avoidance increased with increasing delta T at 0.15 mg/l TRC; (2) minimal increase in avoidance at 0.00, 0.05, and 0.10 mg/l TRC as delta T increased; (3) greatest avoidance occurred at 0.10 mg/l TRC and 6 degrees C delta T; and (4) TRC was the most important factor influencing avoidance. A significant difference was found between avoidance models of the group and individual tests: greater avoidance generally occurred at most test conditions during the group tests. The data collected in this study showed the importance of testing methods when evaluating the avoidance responses of a strongly schooling species exposed to simultaneous chlorine and delta T conditions simulating a power-plant effluent.

Behavioral modification of estuarine fish exposed to sulfur dioxide

This study was designed to determine the avoidance responses of juvenile striped bass (Morone saxatilis) and Atlantic menhaden (Brevoortia tyrannus) exposed to sulfur dioxide (sulfite) at acclimation temperatures of 15, 20, 25, and 30 degrees C. Predictive models were developed and compared for each species at each acclimation temperature. Striped bass avoided 2.2, 2.3, 3.0, and 3.5 mg sulfite/l at 15, 20, 25, and 30 degrees C, respectively. Atlantic menhaden avoided 3.2, 3.6, 2.9, and 3.0 mg sulfite/l at acclimation temperatures of 15, 20, 25, and 30 degrees C, respectively. Acclimation temperature was an important factor influencing the avoidance response of each species exposed to sulfur dioxide. Striped bass avoided lower concentrations of sulfite than Atlantic menhaden at 15 and 20 degrees C. Both species avoided approximately the same concentration of sulfite at 25 degrees C. Atlantic menhaden avoided lower concentrations of sulfur dioxide than striped bass at 30 degrees C.

Effect of picric and picramic acids on growth of rainbow trout (Salmogairdneri) and American oysters (Crassostreavirginica)

Abstract Juvenile rainbow trout ( Salmo gairdneri ) and American oyster spat ( Crassostrea virginica ) were exposed to sublethal concentrations of picric acid (2,4,6-trinitrophenol) and picramic acid (2-amino-4,6-dinitrophenol) for 42 days. No significant inhibition of growth was observed for rainbow trout exposed to 0.45 and 0.05 mg/L picric acid or 0.23 and 0.02 mg/L picramic acid; however, trout exposed to both compounds developed petechial hemorrhages along the abdomen with > 80% possessing lesions by the end of 42 days. American oysters exposed to 0.45 and 0.05 mg/L picric acid and 0.24 and 0.02 mg/L picramic acid showed significant inhibition of shell deposition during the 42 days of exposure. In addition discoloration of the nacre layer of the shell and body mass was observed in oysters exposed to both compounds by the end of the 42 days. The results of this study show that concentrations

An evaluation of the potential toxicity of treated bleached kraft mill effluent to striped bass (Morone saxatilis walbaum) larvae exposed through metamorphosis to the juvenile stage

Abstract Twenty-day-old striped bass ( Morone saxatilis ) larvae were exposed to a range of treated bleached kraft mill effluent (BKME) concentrations from 0 to 20% effluent by volume (v/v) under continuous flow test conditins. The experimental test concentrations in the 2–20% BKME test aquaria had a BOD 5 which ranged from to 5 mg l −1 , TSS 12–17 mg l −1 , and true color 35–416 mg l −1 . Bleached kraft mill effluent did not kill larvae exposed to it for 20 days through metamorphosis to the juvenile stage. The BKME did not alter growth in length, weight or condition factor in larvae over the 20-day exposure period as determined by multiple regression analysis. A linear regression analysis on the dry weight data at Day 20 only, however, indicated a trend of decreasing weight with increasing BKME concentration. Effluent-exposed larvae also developed normally during the 20-day study. All individuals examined completed the transformation from postlarvae to juveniles by the age of 40 days.

Comparative toxicity of Solvent Yellow 33 [2-(2′-quinolinyl)-1,3-indandione] and Solvent Green 3 (1,4-di-p-toluidinoanthraquinone) dyes to freshwater organisms

Abstract Solvent Yellow 33 and a Solvent Green 3 mixture (30:70 mixture of Solvent Yellow 33 and Solvent Green 3) were not acutely toxic to seven of nine freshwater species when tested at the solubility limits of the dyes in freshwater. A solubility limit solution of the Solvent Green 3 mixture killed 50% of the rainbow trout tested for 96 h but was non-toxic when diluted by 50%. Both dyes caused a reduction in green algal growth at solubility limits. The Solvent Green 3 mixture was the most detrimental causing a 98–99% reduction in growth after 5 days of exposure.

Control of Colonial Hydroid Macrofouling by Free-Field Ultrasonic Radiation

Free-field ultrasonic radiation inhibited the feeding of the macrofouling hydroid Garveia franciscana by causing tentacle contraction at the sonic degasification threshold. Within the frequency range of 250 to 2000 kilohertz, the threshold sound intensity (sonic degasification threshold) that caused tentacle contraction was directly proportional to frequency, with the minimum observed being 0.6 watt per square centimeter at 250 kilohertz. A pulse length of 0.2 second and interpulse period of 102 seconds gave the lowest average power required to produce tentacle contraction at a peak pulse sound intensity of 6.2 watts per square centimeter with a frequency of 250 kilohertz. Twenty-four hour exposures to the sound regime caused destruction of the hydranths and regression of tissue in the stolons.

The effect of acclimation temperature on the interactions of chlorine, ΔT and exposure duration to eggs, prolarvae and larvae of striped bass, Morone saxatilis☆

Abstract The effect of five acclimation temperatures on the interactions of total residual chlorine (TRC) (0.00, 0.15 and 0.30 mg l−1, ΔT (2, 6, 10°C above acclimation temperature) and exposure duration (0.08, 2.0, 4.0 h) conditions were evaluated for striped bass, Morone saxatilis, eggs, prolarvae and larvae. The range of acclimation temperatures (12.5, 15.0, 17.5, 20.0, 22.5°C for eggs and prolarvae; 15.0, 17.5, 20.0, 22.5 and 25.0°C for larvae) tested with each life stage included the lower, optimum and upper environmental temperatures that exist when these life stages may be subjected to power plant chlorination conditions. All organisms were tested using a fractional composite design in a 3 × 3 × 3 factorial matrix. Mortality of the eggs was highest at temperatures below 17.5°C; overall mortality decreased with increasing acclimation temperature. The factor causing the greatest effect with this developmental stage was ΔT, followed by TRC and exposure time. Mortality of striped bass prolarvae increased with acclimation temperature after exposure to interacting treatment factors. Interactions involving TRC were most important from 12.5 to 17.5°C; ΔT interactions were prominent at acclimation temperatures of 20.0 and 22.5°C. Larvae mortality was highest at 20°C with a gradual decrease at 25.0°C. Interactions involving ΔT, TRC and exposure time all contributed to the mortality of this life stage; TRC and ΔT caused the main effects. Striped bass eggs were the most resistant life stage; mean mortality averaged over all acclimation temperatures was approximately the same for prolarvae and larvae.

ULTRASONICS FOR INHIBITING BIOFOULING

Ultrasonics has been investigated as an alternative to biocides such as chlorine for inhibiting the growth of the colonial hydroid, Garveia franciscana in the precondenser intake structures of power plants. This hydroid is a particular problem at power plants that use salt water for cooling because it grows rapidly and forms dense matts that can severely restrict the flow of cooling water. Using free-field ultrasonic radiation, acoustic parameters were sought that would yield the most energy-efficient method of causing tentacle contraction of the hydranths, thus inhibiting feeding and/or growth. At all frequencies tested, the sound intensity threshold that caused tentacle contraction coincided with the sonic degasification threshold.