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Hylebos Waterway Fish Injury Studies

Individual Data and Quality Assurance Results

CASE NARRATIVE

Reproductive Injury in Flatfish

Somatic Indices

Calibrations

Prior to initiation of the study, balances were calibrated to insure their accuracy. Balances were

re-zeroed between weight determinations.

Data Validation

Data on length, total weight, gutted weight, gonad weight, and liver weight were initially

recorded in field records by necropsiers, and subsequently entered into the database. Fish length

was determined to the nearest mm, total weight and gutted weight to the nearest g, and gonad

weight and liver weight to the nearest 0.5 g. Database entries were then compared with values

recorded in field data notebooks and any errors or discrepancies were corrected. If recorded

values were illegible, obviously in error (e.g., gutted body weight greater than total body weight),

or specified as guesses or estimates in the field notebooks, data were not used.

Calculation of Somatic Indices

As described in the Sampling and Analysis Plan, somatic indices were calculated according to

the following formulas, using an EXCEL spreadsheet:

Gonadosomatic index (GSI) = (ovary weight (g)/gutted body weight (g)) x 100

Hepatosomatic index (HSI) = (liver weight (g)/gutted body weight (g)) x 100

Condition factor = gutted body weight (g)/length3

 (cm)

Distributions of calculated values were plotting using Statview to check for outliers. In cases

where outliers were noted, data (e.g., lengths, organ weights) were re-checked and any errors

corrected.

Commentary on Missing Data

Specimens 943311,943312,943719. Liver weights and HSI are missing because necropsiers

either forgot to weigh livers or to record organ weights:
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Specimens 943515,943592,943764. Gutted weights are missing, as well as all other indices (GSI,

HSI, and condition factor) whose calculation is based on gutted weight, because necropsiers

either forgot to weigh carcasses or to record carcass weights.

Specimens 943387 and 943469. Liver weights could not be accurately determined due to rough

weather and recorded values were noted as estimates. Consequently these liver weight values

were not entered into the database, and HSI was not calculated.

Specimen 943544. The field-recorded value for gutted weight was greater than the value for total

weight, so neither was entered into the database, and GSI, HSI, and condition factor were not

calculated

Sequential gaps in the specimen numbers do not represent missing fish. Specimen number listed

in Table 1 are female English sole reported in the Reproductive Injury study. Specimen number

not listed were either reported in the Toxicopathic Injury study, or assigned to other projects.

Additional Changes Since the Previous Case Narrative

Revisions 2/24/97

Specimen 943305. The field recorded value for gutted weight for this specimen was 194 g, which

was anomalously low for its total weight of 353 g, as its combined gonad and liver weights were

only 12 g. The 194 g value was probably a recording error, and should have been 294 mm.

Because of the uncertainty of this measurement, gutted weight for this specimen was omitted

from the data set, and GS1, HSL and condition factor were not calculated.

Specimen 943369. The field. recorded value for gutted weight for this specimen was 144 g which

was anomalously low for its total weight of 510 g, as its combined gonad and liver weights were

only 12 g. The 144 g value was probably a recording error. Because of the uncertainty of this

measurement, gutted weight for this specimen was omitted from the data set, and GS1, HSI, and

condition factor were not calculated.

Specimen 943652. The field-recorded value for length for this specimen was 226 mm, which was

anamolously low for its weight of 335 m, and resulted in a condition factor an order of

magnitude greater than the values computed for other specimen. The 226 mm value was

probably a recording error, and should have been 326 mm. Because of the uncertainty of this

measurement, length for this specimen was omitted from the data set, and GSI, HSI, and

condition factor were not calculated.
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Specimen 943655. The field recorded value for gutted weight for this specimen was 364 g, which

was anomalously high for its total weight of 385 g, as its combined gonad and liver weights were

34 g. Simply subtracting the weight of these organs, without even considering the weight of the

other internal organs and any food in the animals digestive tract, the gutted weight should have

been 351 g. The 364 g value was probably a recording error. Because of the uncertainty of this

measurement, gutted weight for this specimen was omitted from the data set, and GSI, HSI, and

condition factor were not calculated.
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