Ecology and Evolutionary Biology Commons^™

Life History Of The Utah Sculpin Cottus Bairdi Semiscaber (Cope) In Logan River, Utah, William M. Zarbook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of the Utah sculpin in Logan River was based on 801 specimens collected during 1949 to March 1951. Numbers of fish examined for various catagories of the study wares length-frequency, 495; aging by vertebrae, 407; length-weight relationship, 601; and food habits, 275.

Fish were collected by use of an electric shocking machine generating 600 watts and 220 volts. Numbers of fish occurred as high as 150 per tenth mile of stream. Preferred habitats occurred in areas of coarse gravel and small rocks.

Vertebrae dissected from the fish were used in age determination. Length-frequency proved to be a general …

A New Method For The Quantitative Determination Of Plankton Hauls, Henry B. Ward

Studies from the University of Nebraska Zoological Laboratory

Only two methods of estimating the quantity of plankton obtained in a haul of the vertical net are known to me. These two may be called the volumetric and the gravimetric. Both have been used by observers in various parts of the world, but so far as I know have never been comparatively tested in order to ascertain the relative value of results obtained by the two. The experience of the past year has shown some disadvantages in the first method, while the second has certain evident objections which rendered its employment in this case out of the question. In …