Daniel E. Shoup

Fish growth early in life typically affects recruitment to adulthood. For this reason, fisheries managers stock fish of varying sizes (e.g., fingerling or advanced fingerling rather than fry, which are less expensive to produce) hoping that an initial size advantage results in improved survival. Saugeye (Sander vitreus x S. canadensis) are hatchery-produced hybrids that are stocked into many Midwestern and southern U.S. reservoirs to create sportfishing opportunities. A saugeye stocking program was initiated at Arcadia Reservoir, Oklahoma, in 2017 when 38,110 fingerlings were stocked. In...

Geographical range of a species can be limited by environmental conditions such as temperature. This is important to understand when trying to establish a new fish population on the fringe of their range. The Oklahoma Department of Wildlife Conservation (ODWC) has been stocking tiger muskellunge (Esox masquinongy x E. lucius) in Lake Carl Etling in northwestern Oklahoma since 2014 with little success. This reservoir experiences a broad range of temperatures that could affect recruitment of tiger muskellunge, especially during times of the year when prey are not abundant. To explore the...

Saugeye are hatchery produced hybrids (female walleye [Sander vitreus] and male sauger [S. canadensis]) that have been introduced to aquatic systems throughout the United States. The Oklahoma Department of Wildlife Conservation (ODWC) stocks reservoirs throughout Oklahoma with saugeye to control overcrowded, stunted white crappie (Pomoxis annularis) populations and to provide recreational fishing opportunities. Because sacrificing fish regularly to remove otoliths for age estimation is often unpopular with anglers, a non-lethal means of obtaining age estimates for saugeye to describe...

The majority of piscivores found in southern U.S. reservoirs consume primarily age-0 (≤100mm) gizzard shad (Dorosoma cepedianum). However, gizzard shad grow rapidly, so even systems with high gizzard shad biomass could be food-limited if most gizzard shad are too large to be eaten. Previous studies comparing gizzard shad abundance and piscivore prey demand have only considered one or a few piscivores, but many southern reservoirs have seven or more piscivores in the community. This suggests prey limitation may be more common than these studies suggest. We used 29 years of data from the...