Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Wildlife Management


Food habits of bigmouth buffalo fry, subadults, and adults were studied in lake Poinsett, South Dakota, from January to November, 1968. Fifty-six fry fed primarily (75.0% by volume) on benthic organisms. Four hundred fifty-five subadults and adults fed entirely on plankton. Daphnia pulex adults comprised 83.7 to 96.7% of the food items during periods of ice cover (January to April). Daphnia pulex adults and juveniles comprised 68.5% by volume and cyclopoid copepods 29.7%^ of the diet from April to July. Summer (July to October) samples showed ingestion of D. pulex adults and juveniles (36.9%), Anacystis sp. (22.3%), and Daphnia galeata mendotae (16.0%). Fall (October) samples showed ingestion of D. Pulex (adults and juveniles) and D. galeata mendotae which totaled 60.9%. Cyclopoid copepods contributed 23.0%. Food selectivity of subadult and adult bigmouth buffalo for eight categories of zooplankton was determined using the index described by Ivlev (1961). Selectively for D. pulex averaged +0.48 for the sampling period. Calanoid copepods were negatively selected for the entire period with a mean of -0.74. The other six categories (Diaphanasoma bryachyurum, Daphnia galeata mendotae, Daphnia pulex juveniles, Bosmina longirostris, Chydorus sphaericus, and cyclopoid copepods) appeared to be taken when available; without selection. Selectivity appeared to be dependent on the morphology of the gill rakers for all organisms except calanoid copepods which appeared to avoid ingestion.

Library of Congress Subject Headings

Fishes -- Food
Lake Poinsett (S.D.)


Includes bibliographical references (pages 30-31)



Number of Pages



South Dakota State University


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