Abundance, Spatiotemporal Distribution, and Growth of Bluegill and Redear Sunfish Fry in a 0.6-ha Pond

Abstract

ABSTRACT The temporal spawning distributions and certain aspects of the early life-histories of bluegill (Lepomis macrochirus) and redear sunfish (L. microlophus) were compared in a recently stocked 0.6-ha pond in central illinois. Redear sunfish spawned earlier, at lower temperatures, and for a shorter interval than did bluegill. Age-0 redear sunfish were primarily restricted to littoral habitats; in contrast, age-0 bluegill occupied both limnetic and littoral habitats, but they became increasingly restricted to littoral habitats as their size increased. First-summer growth rates of early-spawned individuals of the two species were similar, but late-spawned redear sunfish grew significantly slower than similarly-aged bluegill. However, because redear sunfish spawned earlier, in September their young were generally larger ([Xbar]TL = 39.0 mm) than bluegill young ([Xbar]TL = 25.8 mm). Age-0 bluegill were much more abundant than age-0 redear sunfish in September (57 to 1). Inconsistent reproductive success is implicated as a factor limiting recruitment in redear sunfish populations.