Population Characteristics and Ecological Role of Northern Pike in Shallow Natural Lakes in Nebraska

Abstract

Northern pike Esox lucius were sampled in Nebraska's Sandhill lakes during 1998 and 1999 to determine population characteristics and their influence on the fish community in these shallow, warm lakes at the southwestern edge of this species' natural range. Density‐dependent growth, size structure, and condition were not evident in the northern pike populations sampled. Relative abundance of largemouth bass Micropterus salmoides was positively related to size structure of yellow perch Perca flavescens and bluegills Lepomis macrochirus when northen pike were absent. When northern pike and largemouth bass populations were sympatric, these relationships were less evident. Population size structure of yellow perch was lower in lakes with northern pike, but decreased size structure was not evident for bluegills. Northern pike growth decreased with July bottom water temperature, which ranged from 20°C to 25°C. Recruitment patterns of northern pike in the Sandhill lakes appeared to be lake‐specific, strong and weak year‐classes occurring in the same year among different populations. Northern pike in these shallow, warm lakes act as a top‐down predator and appear to structure fish communities predominated by largemouth bass and panfish. Biologists managing warmwater Midwestern lakes thus should consider the effect of northern pike on fish communities.

Growth, condition, diet, and consumption rates of northern pike in three Arizona reservoirs

“…In Parker Canyon Lake, northern pike consumed similar prey as largemouth bass, bluegill, and green sunfish; thus, competition between northern pike and largemouth bass may have occurred if the prey base was limited. We also found northern pike consume largemouth bass (Gurtin et al 1996, Soupir et al 2000, Paukert and Willis 2003. However, studies on the food habitats of northern pike in other areas have found that centrarchids are not a preferred prey (Beyerle 1971, Mauck and Coble 1971, Weithman and Anderson 1977, but are usually eaten when other more preferred prey are unavailable.…”

“…Northern pike typically act as a top-down predator that influences fish communities (Casselman and Lewis 1996). In sympatric populations of largemouth bass and northern pike in Nebraska's Sandhill lakes, the relative abundance of largemouth bass was reduced when compared to lakes where northern pike were absent (Paukert and Willis 2003). These reductions were either due to direct predation or competition with largemouth bass for similar food resources.…”

Spawning population characteristics of pike Esox lucius L. in Lake Rubikiai (Lithuania)

“…According to the data of Paukert and Willis [25], of 11 populations of pike in Nebraska's Sandhill, only 2 had fish older than 6 years. Alessio [43] stated that within Italian populations most pike did not exceed 4-5 years of age and only a few attained 8-10 years of age.…”

“…Seasonal variation in water level is commonly cited as a factor strongly influencing the year-class formation of pike [18,[22][23][24]. Pauker and Willis [25] noted that strong and weak year-classes could occur among different pike populations in the same year, depending upon lake characteristics and environmental factors. Probst et al [26] observed in a literature review that the year-class strength of fish is usually determined during their early life history stages because the highest rates of mortality within a cohort usually occur during the egg, larval and juvenile stages.…”

Diet of Grass Pickerel (Esox americanus vermiculafus) in Indiana Streams

“…For example, Guenther and Spacie (2006) found increased redfin pickerel (= grass pickerel) in streams that were not associated with downstream reservoirs. The northern pike is thought to structure fish communities primarily through predation (Paukert and Willis 2003), and this scenario could be applied to the grass pickerel in Indiana. Piscivores are usually thought to be present in low abundance in assemblages, because they are primarily feeding on fish and occupy the highest trophic level (Gerking 1994).…”