Food Habits of Walleye and Saugeye When Stocked as Secondary Predators into Small South Dakota Impoundments

This study focused on food habits of sympatric largemouth bass Micropterus salmoides and walleye Stizostedion vitreum populations and sympatric walleye and saugeye Stizostedion vilreum X Stizostedion canadense populations in one South Dakota natural glacial lake and three South Dakota small impoundments. The food habits study of sympatric largemouth bass and walleye populations was conducted in 1998 at Enemy Swim and Byre lakes South Dakota, where South Dakota Game, Fish and Parks (SDGFP) personnel had previously established the percid populations. In 1999, the food habits study of sympatric walleye and saugeye populations was conducted in Jones and Tunkisula lakes, South Dakota, where South Dakota State University (SDSU) had previously established the percid populations. Food habits of two primary predators, largemouth bass and walleye, were compared in a small South Dakota impoundment (51-ha Byre Lake) and a large South Dakota natural glacial lake (868-ha Enemy Swim Lake). My objectives were to determine seasonal trends in diets, and to compare the selection of various panfish species by the predators in different environments in 1998. In both lakes, substock (<200 mm) largemouth bass primarily consumed fishes, and few aquatic insects. Larger (200- 380 mm) largemouth bass primarily consumed fishes in Enemy Swim Lake, while larger bass in Byre Lake fed more extensively on crayfish and aquatic insects during spring and summer, and on fishes only during the fall. Walleye food habits by length group were similar between lakes. Walleye less than 380 mm in length fed extensively on aquatic insects during the spring, and then fed primarily on fishes during summer and fall. Walleye longer than 380 mm fed primarily on fishes during spring and fall, while aquatic insects made up a substantial portion of the diet during summer. Largemouth bass in Byre Lake fed more on yellow perch Perea flavescens than bluegill Lepomis macrochirus, except for the substock bass that consumed only bluegills during fall. Largemouth bass in Enemy Swim Lake fed more extensively on yellow perch than bluegill. In both lakes, walleye fed primarily on yellow perch during spring and summer, and extensively on bluegill during the fall. Thus, walleye food habits were quite similar between the two lakes, while largemouth bass diets differed to a greater extent. Food habits of two sympatric predator populations, saugeye and walleye, were compared in two small South Dakota impoundments (41-ha Jones Lake and 9-ha Lake Tunkisula). My objectives were to determine seasonal trends in diets, and to compare the selection of various panfish species by the predators in different environments in 1999. In Jones Lake, survival of walleye and saugeye stocked during 1997 and 1998 was relatively low; for example, we collected only l O age-1 and age-2 walleye per hour of night electrofishing during the spring of 1999, and collected saugeye (age I and 2) at 3/h. Both walleye and saugeye fed primarily on fishes and invertebrates throughout seasons, but walleye demonstrated a more diverse selection of prey fishes in the fall. In Lake Tunkisula, survival of stocked walleye and saugeye was much higher; spring night electrofishing samples collected 223 walleye/h and 78 saugeye/h in 1999 (ages I and 2 combined). Walleye and saugeye primarily fed on invertebrates in the spring. Both walleye and saugeye shifted their diets when age-0 fishes became available in the summer and fall with saugeye consuming a more diverse selection of prey fishes. In addition, saugeye fed extensively on black bullheads Ameiurus me/as while walleye did not. A winter gill-net sample was conducted on Lake Tunkisula in February 1999. Walleye were found to feed exclusively on invertebrates during winter while saugeye incorporated fishes in their diet. Regardless of differences in these two water bodies, diet overlap between walleye and saugeye was always substantial, but declined in the fall.

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis - University Access Only

Discipline thesis:degree_discipline

Wildlife and Fisheries Science

Year

2000

Author dc:creator

• Walter, Dray D.

Contributors dc:contributor

• David W. Willis

• Natural Resources and Conservation

Statement dc:rights

• Copyright © 2000 Dray D. Walter. All rights reserved.

Language dc:language

en

Repository record dc:identifier

https://openprairie.sdstate.edu/etd/592

OAI identifier oai:identifier

oai:openprairie.sdstate.edu:etd-1592