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Wayne A. Hubert

Publications and source records attributed to Wayne A. Hubert.

10 recordsLinked to original sources
USGS2015

Fish assemblage shifts in the Powder River of Wyoming: an unregulated prairie river system previously considered to be relatively pristine.

W y oming ’ s P owder River is considered an example of a pristine prairie river system. While the river hosts a largely native fish assemblage and remains unimpounded over its 1,146-km course to the Y ellowstone River confluence, the hydrologic regime has been altered through w ater dive rsion for agriculture and natural gas extraction and there has been limited study of fish assemblage structure. W e analyzed fish data collected from the mainstem P owder River in W yoming between 1896 and 2008. Shifts in presence/absence and relative abundance of fish species, as well as fish assemblage composition, were assessed among historical and recent samples. The recent P owder Rive r fish assemblage w as characterized by increased relative abundances of sand shiner Notr opis stramineus and plains killifish Fundulus zebrinus , and decreases in sturgeon chub Macrhybopsis gelida . Shifts in fish species relative abundance are linked to their reproductive ecology with species with adhesive eggs generally increasing in relative abundance while those with buoy ant drifting eggs are decreasing. Assemblage shifts could be the result of landscape level changes, such as the loss of extreme high and low flow events and changing land use practices.

Montana, Wyoming↗
USGS2009

Coldwater fish in small standing waters

This chapter describes standard techniques for sampling coldwater fishes in small standing waters. Within the context of this book, coldwater fish species are those that prefer water temperatures less than 15°C, and small standing waters are lakes and reservoirs where surface area is less than 200 ha. Chapter 7 of this book describes sampling coldwater fishes in large standing waters (i.e., surface area > 200 ha). The criterion that separates small and large waters is arbitrary and does not imply that different methods are required depending on, for example, whether a lake is 199 or 201 ha. Two chapters are dedicated to sampling coldwater fishes in standing waters because lake size varies by several orders of magnitude and some differences in sampling methods are needed to achieve efficient sampling at both ends of the lake-size continuum. Although it is clear that some differences in methods are necessary to accommodate extremes in lake sizes, it is not clear when the transition from methods for small lakes to methods for large lakes should apply. To bridge this gap, we describe methods of sampling coldwater fish in small lakes and reservoirs that are compatible with a subset of the methods proposed for coldwater fish in large lakes and reservoirs (see Chapter 7). The method proposed for sampling coldwater fish in small standing waters is depth-stratified summer gill netting. We acknowledge that coldwater species often inhabit the same lakes and reservoirs as warmwater fish. Thermal stratification during summer influences the depth distribution of coldwater and warmwater species, and a depth-stratified survey can sample both temperature guilds. For this reason, gill-netting methods for sampling coldwater fishes have been chosen so that they are compatible with gill-netting methods proposed for sampling warmwater fishes (i.e., Chapters 2 and 3).

Book chapter↗
USGS2009

Standard methods for sampling North American freshwater fishes

This important reference book provides standard sampling methods recommended by the American Fisheries Society for assessing and monitoring freshwater fish populations in North America. Methods apply to ponds, reservoirs, natural lakes, and streams and rivers containing cold and warmwater fishes. Range-wide and eco-regional averages for indices of abundance, population structure, and condition for individual species are supplied to facilitate comparisons of standard data among populations. Provides information on converting nonstandard to standard data, statistical and database procedures for analyzing and storing standard data, and methods to prevent transfer of invasive species while sampling.

Book↗
USGS2000

Effects of fall-to-winter changes in habitat and frazil ice on the movements and habitat use of juvenile rainbow trout in a Wyoming tailwater

Overwinter declines in the abundance of small rainbow trout Oncorhynchus mykiss have been observed in a section of the Big Horn River that lies downstream from Boysen Reservoir, where reservoir releases prevent surface ice formation. To provide insight into the possible causes of these declines in abundance, radiotelemetry was used to determine movement and microhabitat use of juvenile (20–25 cm total length) rainbow trout during the fall and winter of 1995–1996. Throughout the fall and winter, both stocked (hatchery) and naturally spawned (wild) fish were generally found in main-channel pools with cover that reduced current velocities to less than 2 cm/s near the bottom and with nearby (<2 m) water velocities that were greater than 15 cm/s. These locations provided refuges from the current, with adjacent flowing water that could deliver drifting aquatic invertebrates. The fish were generally associated with cover that was formed by aquatic vegetation early in the fall, but they shifted to cobble and boulder cover (in deeper water) as the aquatic vegetation decomposed and as winter progressed. Episodes of frazil ice in January and early February were associated with movements of wild fish in the upstream portion of the study area—from normal activity areas to refuges at the bottom of deep pools or under shelf ice in shallow water near shore. Frazil-ice episodes often initiated long-term movements among fish. Our results suggest that changing habitat features from fall to winter and frazil-ice episodes can cause juvenile rainbow trout to move and to modify their habitat use, depending on their location in a tailwater.

Wyoming↗
USGS1998

Accuracy and precision of stream reach water surface slopes estimated in the field and from maps

The accuracy and precision of five tools used to measure stream water surface slope (WSS) were evaluated. Water surface slopes estimated in the field with a clinometer or from topographic maps used in conjunction with a map wheel or geographic information system (GIS) were significantly higher than WSS estimated in the field with a surveying level (biases of 34, 41, and 53%, respectively). Accuracy of WSS estimates obtained with an Abney level did not differ from surveying level estimates, but conclusions regarding the accuracy of Abney levels and clinometers were weakened by intratool variability. The surveying level estimated WSS most precisely (coefficient of variation [CV] = 0.26%), followed by the GIS (CV = 1.87%), map wheel (CV = 6.18%), Abney level (CV = 13.68%), and clinometer (CV = 21.57%). Estimates of WSS measured in the field with an Abney level and estimated for the same reaches with a GIS used in conjunction with l:24,000-scale topographic maps were significantly correlated (r = 0.86), but there was a tendency for the GIS to overestimate WSS. Detailed accounts of the methods used to measure WSS and recommendations regarding the measurement of WSS are provided.

North American Journal of Fisheries Management↗
USGS1997

Irregularly shaped otoliths from saugers prevent back-calculation of length at previous ages in Wyoming

We collected otoliths from saugers Stizostedion canadense in Boysen Reservoir, Bighorn Reservoir, and the Bighorn River in Wyoming to evaluate age and growth. All otoliths in our samples (264 fish) were irregularly shaped, and the irregularities became more pronounced with increasing age of the fish. Age estimates with irregular otoliths were possible, but back-calculation of length at previous ages was not possible as a result of radically inconsistent lengths of radii. It should not be assumed that otoliths can be used for back calculation of length at age among all stocks of sauger. The assumption of regular otolith formation within a stock should be tested before obtaining samples of otoliths for age and growth assessment.

Wyoming↗
USGS1996

Estimation of potential maximum biomass of trout in Wyoming streams to assist management decisions

Fishery managers can benefit from knowledge of the potential maximum biomass (PMB) of trout in streams when making decisions on the allocation of resources to improve fisheries. Resources are most likely to be expended on streams with high PMB and with large differences between PMB and currently measured biomass. We developed and tested a model that uses four easily measured habitat variables to estimate PMB (upper 90th percentile of predicted mean biomass) of trout ( Oncorhynchus spp., Salmo trutta , and Salvelinus fontinalis ) in Wyoming streams. The habitat variables were proportion of cover, elevation, wetted width, and channel gradient. The PMB model was constructed from data on 166 stream reaches throughout Wyoming and validated on an independent data set of 50 stream reaches. Prediction of PMB in combination with estimation of current biomass and information on habitat quality can provide managers with insight into the extent to which management actions may enhance trout biomass.

Wyoming↗
USGS1987

Habitat Suitability Index Models: Lark bunting

A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the lark bunting (Calamospiza melanocorys). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

FWS/OBS↗
USGS1984

Habitat Suitability Index Models: Lake trout (exclusive of the Great Lakes)

The lake trout is an important commercial and sport fish in North America. In the Central Rocky Mountain regi on, 1ake trout are common ly referred to as "mackinaw". There is good evidence that lake trout should be called "1 ake charr" (Morton 1980). No subspecies of lake trout is presently recognized (Robins et al. 1980). The species, however, has extreme variability throughout its range, making it difficult to draw general conclusions about its biology (Martin and Olver 1980).

FWS/OBS↗