S. Crawford

Differences in Largemouth Bass Food Habits and Growth in Vegetated and Unvegetated North-central Florida Lakes

Stomachs of 5,818 largemouth bass (Micropterus salmoides) were examined from 10 north-central Florida lakes to determine differences in food habits of largemouth bass in lakes with abundant aquatic macrophytes (vegetated) and lakes nearly devoid of aquatic macrophytes (unvegetated). We found significant differences (P < 0.05) between stomach contents of 6 length groups of largemouth bass (range: 60-640 mm TL) from vegetated and unvegetated lakes. The 152- to 254-mm length group exhibited the greatest number of diet differences. Atherinids, decapods, and odonates were consumed more...

Tag Retention of Hallprint Dart Tags and Tag-induced Mortality in Largemouth Bass

Tag retention and tag-induced mortality were evaluated for 2 sizes of Hallprint® dart tags injected in largemouth bass (Micropterus salmoides). Mean tag retention rates of 98% for larger (81 mm) PDB dart tags and 78% for smaller (69 mm) PDT dart tags were observed during a 15-month study in Lake Blanchester, Florida. Significantly higher tag loss (P ≤ 0.05) of PDT tags was attributed to a more flexible and shorter (12-mm) barb (anchor) compared to the larger and longer (18-mm) barb on the PDB tag. Estimated tag-induced mortality was 13% for bass 260-299 mm using smaller tags, and 18% for...

Reevaluating the Use of Acrylic Tubes for Collection of Largemouth Bass Stomach Contents

Stomach contents of 434 largemouth bass (Micropterus salmoidesfloridanus) were collected with clear acrylic tubes. Sixty-four percent of the bass contained food. No significant differences (P > 0.05) in percent recovery of food items by weight occurred among 3 biologists for the 6 size groups studied. Greater than 80% recovery by weight of all food was obtained with acrylic tubes in 6 size groups of bass ranging from 100 to 590mm TL. Seven percent of bass that yielded no food when sampled with tubes actually contained food. Appropriate tube size was important in efficient food...

Age, Growth, and Mortality of Florida Largemouth Bass Utilizing Otoliths

Age composition, growth, and mortality of largemouth bass (Micropterus salmoides floridanus) populations in 6 major Florida resources were determined. Most largemouth bass were in the first 4 or 5 year classes; however, 6 and 7 year old fish were not uncommon, and largemouth bass up to 12 years of age were collected. Females grew faster and exhibited greater longevity than males. Total annual mortality (A) estimated from catch curves ranged from 0.37 for the Suwannee River to 0.54 in Lake Weir and was within the range reported from other localities. Backcalculated lengths based on...