Joe E. Crumpton

Bias from Age-grouping Black Crappie by Length-frequency as Compared to Otolith Aging

Eighteen hundred and thirty-four black crappie (Pomoxis nigromaculatus) were collected from the St. Johns River, Florida, in late winter and early spring, 1982 to 1985. Differences in numbers and growth rates of males and females collected were not significant (P > 0.05). Fish were separated into age groups using length-frequency distributions and by counting annuli on otoliths. Only 2 distinct age groups were discernible by length-frequency analysis, whereas 6 to 8 groups were identified by otolith aging. Mean lengths of age groups obtained from lengthfrequency were overestimated 3 of...


An Inexpensive Low Voltage Electrofishing Device for Collecting Catfish

A low voltage electrofishing device, commonly called a “monkey rig” in Florida, was used to collect catfish for a tagging study on the St. Johns River, Florida. In 40 fishing trips, 3,234 catfish were captured using the “monkey rig”. This inexpensive device was selective for catfish species only. The 16-V to 18-V alternating current agitated the catfish to the surface but fish never exhibited a complete state of tetanus. When electrofishing in waters with surface temperatures warmer than 24˚ C and around underwater structure, the “monkey rig” was an effective collecting device for catfish...


Effects of Micromagnetic Wire Tags on the Growth and Survival of Fingerling Largemouth Bass

Six hundred sixty fingerling largemouth bass (Micropterus salmoides) were stocked into a 0.1 ha hatchery pond for 69 days to determine if micromagnetic wire tags or the tagging process affected survival and growth rates. Two hundred twenty fingerlings were tagged internally in the vomerine (nasal) cartilage and 220 in the forebrain area. These were costocked with 220 control fingerlings. At recovery, survival rates of vomerine and forebrain tagged bass were comparable (70.5% and 75.9%), but were less than the rate for control fish (93.6%). Tag retention rates for vomerine and forebrain...


Effects of Dummy Radio Transmitters on the Behavior of Largemouth Bass

Twenty largemouth bass (Micropterus salmoides) , 10 containing dummy radio transmitters and 10 control, were studied in hatchery ponds to determine the effects of implanted transmitters on swimming, feeding, spawning and catchability behavior. Eight additional bass were subjected to buoyancy compensation tests under laboratory conditions. Pond studies indicated no significant difference in swimming movement or catchability between transmitter and control bass. Both transmitter and control bass were observed feeding and spawning. All transmitters were encapsulated in a skin-like sac within...


Differences in Growth and Catchability of Natural Bass Populations in Florida

Largemouth bass collected from selected Florida locations and stocked in hatchery ponds were studied for growth and catchability differences. Data indicates that some populations grow faster than others and that females grow faster than males. Experimental fishing data indicates that some populations show trends towards greater catchability, but no one population was shown significantly more catchable.