Predatory Effects of Northern Pike and Largemouth Bass: Bioenergetic Modeling and Ten Years of Fish Community Sampling

Abstract

ABSTRACT Bluegill (Lepomis macrochirus), yellow perch (Perca flavescens), northern pike (Esox lucius), largemouth bass (Micropterus salmoides), and common carp (Cyprinus carpio) were sampled in fall 1992 to 2001 in Pelican Lake, Nebraska using electrofishing, gill netting, and trap netting to evaluate the effects of northern pike and largemouth bass on the introductions of bluegill and perch and the potential effects of northern pike on common carp recruitment throughout a 10-year period. The number of yellow perch per gill net remained low even after over 59,000 adult perch were stocked in 1994. However, the number of bluegill collected per hour of night electrofishing increased from <20 prior to 1997 (when 102, 800 25–50 mm bluegills were stocked) and has typically been >40 since then. The mean number of common carp collected per gill net remained low in all years and protection of northern pike ≥710 mm with a maximum length limit may have aided in controlling carp recruitment. Bioenergetic modeling revealed that the 2001 northern pike population consumed between 49,000 and 77,000 yellow perch, suggesting that these predators can substantially reduce perch abundance.