30 



Fishery Bulletin 



1990 



Table 1 



Initial concentrations of water-soluble fractions (ppm) of Cook 

 Inlet crude oil for each treatment group of walleye pollock 

 eggs. 



Control 

 Low 



Maximum 



0.0 

 0.2 

 0.6 

 1.6 

 2.3 

 3.6 



0.00 



0.08 



0.09 



0.0 



0.4 

 0.8 

 1.5 

 2.2 

 2.8 



0.01 

 0.02 

 0.01 

 0.12 

 0.10 



0.0 



0.3 

 0.7 

 1.8 

 2.8 

 3.1 



0.02 

 0.10 

 0.20 

 0.04 

 0.13 



water-hardening period, all eggs were transferred to 

 fresh seawater of the same treatments. 



Fertilized eggs were exposed to five WSF concen- 

 trations, ranging from controls (0 ppm) through 

 3.6 ppm, beginning at day (fertilization), day 1 

 (morula stage), or day 7 (1 1-14 somite stage) (Table 1). 

 Exposures were static, and after the transfer at 

 2 hours, eggs remained in the same solution until hatch 

 (approximately 21, 20, and 14 days, respectively). Lar- 

 vae that hatched in the 1-21 day treatment were 

 transferred to clean seawater immediately after hatch 

 and observed until yolks were resorbed (~21 days). 

 There were three replicates per concentration, with 

 49-101 eggs per replicate. Maximum biomass did not 

 exceed 0.1 g/L in any replicate. Temperature was con- 

 stant (3.9±0.1°C). Test jars were not aerated, but 

 oxygen was not limiting (97 ± 3% saturation at end of 

 experiment). 



Microbial growth diii not cause problems. Control 

 eggs remained healthy throughout the experiment. 

 Any growth observed in the jars during the experiment 

 was removed by pipette, as were dead eggs and 

 detritus. Bacterial plates inoculated with water col- 

 lected after hatch showed no significant differences 

 between WSF and controls. 



Test conditions were static, simulating a single-event 

 oil spill, but the WSF of Cook Inlet crude oil was pro- 

 duced by dripping seawater through a continuously 

 replenished 40-cm emulsified layer of oil; the resulting 

 WSF was collected below the layer after dispersed oil 

 floated out (Moles et al. 1985). Seawater was filtered 

 through 5-jx glass fiber filters or approximately lO-^i 

 sand filters before contamination with WSF. Concen- 

 trations were routinely monitored with fluorescence 

 spectroscopy and glass-capillary-column gas chroma- 

 tography as described in Carls and Rice (1988). Because 

 polynuclear aromatic compounds were not detectable 



Table 2 



Comparison of water-soluble-fraction (WSF) preparations of 

 Cook Inlet crude oil in treatment groups of walleye pollock 

 eggs from years 1982 (0-21 and 7-21 day treatments) and 1983 

 (1-21 day treatment). Concentrations of compounds in the 

 WSF were measured by gas chromatography and converted 

 to percentages. « = 3 for each compound; asterisks denote 

 significant differences between 1982 and 1983 percentages. 



benzene 50.5 



toluene 34.6 



ethylbenzene* 2.3 



m- and p-xylene 0.2 



o-.\ylene 3.''' 



mesitylene* •'•0 



naphthalene* 1.2 



2-methylnapthalene* 0.6 



1-methylnapthalene f>.,5 



2,6-dimethylnapthalene tl.ll 



1.4-dimethylnapthalene* O.i) 



1.2-dimethylnapthalene' 0.0 



Total mononuclear 



aromatics* 97.7 



Total dinuclear 



aromatics* 2.3 



0.72 

 1.62 

 0.17 

 0.4.5 

 0.28 

 (1.15 

 0.15 

 0.06 

 0.02 

 0.0(1 

 0.00 

 0.00 



51.0 

 30.3 

 0.2 

 4.5 

 2.8 

 0.1 

 10.5 

 0.0 

 0.3 

 0.0 

 0.1 

 0.2 



88.9 



11.1 



66 



89 

 22 

 27 

 18 

 .03 

 .87 

 00 

 12 

 00 

 .04 

 04 



in the WSF, concentrations are reported as total mono- 

 plus diaromatic hydrocarbons in ppm. The comi)osition 

 of the WSF was similar in 1982 and 1983; the principal 

 difference was a higher percentage of naphthalene in 

 1983 (10.5%) than in 1982 (1.2%) (Table 2). 



Developing eggs were examined daily; mortality and 

 number hatched were recorded. A few eggs (2-10/ 

 concentration • treatment) were subsampled daily for 

 observation and measurement. Development was 

 staged according to Yusa (1954). Blastopore diameters 

 were measured with an occular micrometer near the 

 time of closure in the 1-21 day treatment. The presence 

 or absence of morphological abnormalities was 

 recorded. If present, the size of vesicles was coded as 

 very small, small, medium, or large. Dead eggs were 

 also examined for abnormalities and development 

 stage. 



Immediately after hatch, larvae were examined for 

 abnormalities with a microscope; total body length and 

 yolk lengths were measured with an occular microm- 

 eter, except measurements were not made in the 1-21 

 day treatment. Yolk lengths were measured along the 

 major body axis, and were considered proportional to 

 yolk volume. Mortality and the number abnormal were 

 counted for each replicate. 



