Publications

Studies of sea otters in captivity began in 1932, producing important insights for conservation. Soviet (initiated in 1932) and United States (1951) studies provided information on captive otter husbandry, setting the stage for eventual large-scale translocations as tools for population restoration. Early studies also informed effective housing of animals in zoos and aquaria, with sea...

We studied habitat selection by northern spotted owls (Strix occidentalis caurina) during natal dispersal in Washington State, USA, at both the roost site and landscape scales. We used logistic regression to obtain parameters for an exponential resource selection function based on vegetation attributes in roost and random plots in 76 forest stands that were used for roosting. We used a...

We explored potential negative effects of exotic brown trout (Salmo trutta) on native sculpin (Cottus sp.) on the Logan River, Utah, USA by (i) examining factors most strongly correlated with sculpin abundance (e.g., abiotic conditions or piscivory?), (ii) contrasting the extent of brown trout predation on sculpin with that by native cutthroat trout (Oncorhynchus clarkii utah) and (iii)...

Changes in temperature and seasonality resulting from climate change are heterogeneous, potentially altering important sources of natural selection acting on species phenology. Some species have apparently adapted to climate change but the ability of most species to adapt remains unknown. The life history strategies of migratory animals are dictated by seasonal factors, which makes these...

Reservoirs impounded over floodplain rivers are unique because they may include within their upper reaches extensive shallow water stored over preexistent floodplains. Because of their relatively flat topography and riverine origin, floodplains in the upper reaches of reservoirs provide broad expanses of vegetation within a narrow range of reservoir water levels. Elsewhere in the...

Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native...

The processes influencing animal movement and resource selection are complex and varied. Past efforts to model behavioral changes over time used Bayesian statistical models with variable parameter space, such as reversible-jump Markov chain Monte Carlo approaches, which are computationally demanding and inaccessible to many practitioners. We present a continuous-time discrete-space (CTDS...

It has been conjectured that reservoirs differ in the rate at which they manifest senescence, but no attempt has been made to find an indicator of senescence that performs better than chronological age. We assembled an indicator of functional age by creating a multimetric scale consisting of 10 metrics descriptive of reservoir environments that were expected to change directionally with...

The Robust Redhorse Moxostoma robustum is a rare and imperiled fish, with wild populations occurring in three drainages from North Carolina to Georgia. Hydroelectric dams have altered the species’ habitat and restricted its range. An augmented minimum-flow regime that will affect Robust Redhorse habitat was recently prescribed for Blewett Falls Dam, a hydroelectric facility on the Pee...

Rapid growth of black bass (Micropterus spp.) tournaments in the 1960s and 1970s caused concern among fisheries managers and anglers about the impacts of tournament-caused mortality on bass populations. Tournament organizers voluntarily implemented live-release events in the early 1980s. As catch-and-release practices became more common, procedures to improve the survival of tournament...

No abstract available.

The global proliferation of dams within the last half century has prompted ecologists to understand the effects of regulated rivers on large-river fishes. Currently, much of the effort to mitigate the influence of dams on large-river fishes has been focused on downriver effects, and little attention has been given to upriver effects. Through a combination of field observations and...