An Experimental Analysis of Macrophyte Growth Forms as Fish Foraging Habitat

In this laboratory study we measured the independent effects of macrophyte growth form, plant density, and prey abundance on the foraging rate of the pumpkinseed sunfish (Lepomis gibbosus). We demonstrate that macrophyte growth forms are not all similar in their effects on fish foraging. Prey capture rates of pumpkinseeds foraging among Scirpus validus (cylindrical stems) were 53 and 365% times greater than for Potamogeton amplifolius (leafy stems) for cladoceran (Sida crystallina) and larval damselfly (Coenagrionidae) prey, respectively. Plant growth form influenced prey capture rates more than charges in natural plant density. Plant density effects ranged from none on damselfly capture rates to a 29% decline in cladoceran capture rate over a twofold increase in plant density. Our results indicate that in plant-structured habitats, variation in plant growth form can be an important determinant of fish foraging and habitat associations.

[1]  T. Moermond.  Habitat Constraints on the Behavior, Morphology, and Community Structure of Anolis Lizards , 1979 .

[2]  A. Keast,et al.  Daily Feeding Periodicities, Food Uptake Rates, and Dietary Changes with Hour of Day in Some Lake Fishes , 1968 .

[3]  D. J. Hall,et al.  Experimental Tests of Optimal Habitat Use in Fish: The Role of Relative Habitat Profitability , 1983 .

[4]  J. Downing,et al.  Empirical Relationships of Phytomacrofaunal Abundance to Plant Biomass and Macrophyte Bed Characteristics , 1988 .

[5]  A. Keast.  Feeding Interrelations Between Age-Groups of Pumpkinseed (Lepomis gibbosus) and Comparisons with Bluegill (L. macrochirus) , 1978 .

[6]  W. B. Scott,et al.  Freshwater fishes of Canada , 1974 .

[7]  Jacqueline F. Savino,et al.  Predator-Prey Interaction between Largemouth Bass and Bluegills as Influenced by Simulated, Submersed Vegetation , 1982 .

[8]  A. Robertson.  Trophic interactions between the fish fauna and macrobenthos of an eelgrass community in Western Port, Victoria☆ , 1984 .

[9]  E. Ogden.  The broad-leaved species of Potamogeton of Noth America north of Mexico , 1943, Contributions from the Gray Herbarium of Harvard University.

[10]  Larry B. Crowder,et al.  Habitat structural complexity and the interaction between bluegills and their prey , 1982 .

[11]  Donald J. Hall,et al.  Ontogenetic Habitat Shifts in Bluegill: The Foraging Rate‐Predation Risk Trade‐off , 1988 .

[12]  V. Gotceitas,et al.  Selection between Densities of Artificial Vegetation by Young Bluegills Avoiding Predation , 1987 .

[13]  D. Goldberg,et al.  Equivalence of competitors in plant communities: a null hypothesis and a field experimental approach. , 1983 .

[14]  K. Sand‐Jensen,et al.  Distribution and quantitative development of aquatic macrophytes in relation to sediment characteristics in oligotrophic Lake Kalgaard, Denmark , 1979 .