7067

• UCREFRP Catalog Number: 7067
• Author: Banks, J. L.
• Title: Fish Species Distribution in Dinosaur National Monument During 1961 and 1962.
• USFW Year: 1964.
• USFW - Doc Type: Master's Thesis.
• Copyright Material: NO

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Chapter II

MATERIALS AND METHODS

The field program consisted of measuring aquatio environ-
mental factors and colleoting fish and invertebrate speoimens within
the thesis area.

Envirorunental Heasuring Equipment
Environmental factors measured were water and air temper-

ature, water turbidity, and general water chemistry_ Field determinations
for water ohemistry followed closely the prooedures described by Welch

(1948) and Lagler (1956).

Thermometers

A Fbxboro electric resistance thermometer was employed to

determine air and water temperatures during the first half of the

summer and all autumn investigations. Standardized mercury-in-glass

thermometers were used during other periods of field study after

they were calibrated with the electric therDlDmetar. Eleotric

thermometor readings were accurate to approximately one-halt degree F

and mercury ther11DDI8ter readings vlere acaurata to approximately one

degree F.

Secchi disc

An 8-inch secohi disc was used to mea5Ure depths of visi-

bUity aocording to standard methods described by ~~eloh (1948). All

measurements were made in areas whera currents were weak or lacking.

Depth of visibility was used as an index to water turbidity.