Submerged aquatic vegetation habitat use of age-0 Florida bass Micropterus floridanus

Hatchery-raised, age-0 Florida bass Micropterus floridanus are commonly used for fish enhancement efforts to support popular recreational fisheries and are ecologically important as both a food source and consumer. Despite their importance and frequent use of submerged aquatic vegetation (SAV) habitats, critical information is lacking on the specific characteristics of SAV that influence habitat occupancy. Using the SAV species Vallisneria americana and Potamogeton illinoensis, which are native to the southeast USA, and the invasive SAV Hydrilla verticillata, we conducted seven different habitat choice experiments to examine hatchery-raised, age-0 M. floridanus habitat use of different SAV populations (i.e., hydrologically isolated collection sources of varied physical characteristics), population diversity (i.e., increased richness of genotypically and phenotypically variable SAV), species, and species diversity (i.e., increased species richness). Fish spent more time in taller, larger V. americana but did not seem to favor any particular P. illinoensis population, SAV species, or species diversity tested. Additionally, fish spent more time in increased V. americana population diversity when the populations used were randomized, but fish spent more time in decreased population diversity when their favored V. americana population was used in all choices. This research adds additional nuance to our understanding of optimal vegetation for fish habitat use and is informative for future SAV plantings and invasive SAV management aimed at maximizing fish habitat and restoring recreational fisheries.

Automated summary

The study found that age-0 Florida bass prefer taller and larger Vallisneria americana, but did not show a particular preference for different populations of Potamogeton illinoensis, SAV species, or species diversity. Additionally, fish spent more time in increased Vallisneria americana population diversity when populations were randomized, but spent more time in decreased population diversity when their favored Vallisneria americana population was used in all choices.