Paul H. Michaletz

Relations among Angler Use, Harvest, and Stocking Rates of Channel Catfish in Missouri Impoundments

We examined relations among creel statistics and stocking rates of channel catfish (Ictalurus punctatus) in small impoundments. Angling effort directed toward catfish varied from 2 to 790 hours ha−1 and made up between 1% and 62% of the total angling effort. Anglers harvested nearly all of the channel catfish they caught in most impoundments. Harvest of channel catfish varied from 0.4 to 126 fish ha−1 and 0.3 to 74 kg ha−1 and was more closely associated with catfish angling effort than with stocking rate. Harvest rate declined asymptotically with...


Diets and Factors Affecting Feeding Success of Age-0 Gizzard Shad

Diets, food selection, and factors affecting feeding success of small (5-9 mm total length, TL), medium (10-19 mm TL), and large (20-29 mm TL) larval and early juvenile gizzard shad (Dorosoma cepedianum) were examined in 2 large Missouri reservoirs. Diets and food selection shifted from mainly copepod nauplii and cyclopoids to rotifers and phytoplankton as fish grew. Mean length of ingested zooplankton rose slightly as gizzard shad grew from the small to medium length groups and then decreased for the large length group. Feeding success (feeding incidence and mean gut fullness) increased...


Comparison of Electrofishing and Gill Netting for Sampling Gizzard Shad

Gill netting (mesh sizes from 13 to 64 mm) and electrofishing were conducted in April and October 1987-1989, to compare their utility for providing precise estimates of relative abundance and size structure of gizzard shad (Dorosoma cepedianum) populations in 2 Ozark impoundments. Catches of gizzard shad <120 mm were extremely variable for electrofishing and very low for gill netting and were excluded from further analysis. Electrofishing captured more gizzard shad ≥120 mm with less effort (68-339 fish/hour) than gill netting (2-48 fish/net day). However, neither method provided precise...