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Density of American black bears in New Mexico
Considering advances in noninvasive genetic sampling and spatially explicit capture–recapture (SECR) models, the New Mexico Department of Game and Fish sought to update their density estimates for American black bear (Ursus americanus) populations in New Mexico, USA, to aide in setting sustainable harvest limits. We estimated black bear density in...Gould, Matthew J.; Cain, James W.; Roemer, Gary W.; Gould, William R.; Liley, Stewart
Energetic fitness: Field metabolic rates assessed via 3D accelerometry complement conventional fitness metrics
Evaluating the fitness of organisms is an essential step towards understanding their responses to environmental change. Connections between energy expenditure and fitness have been postulated for nearly a century. However, testing this premise among wild animals is constrained by difficulties in measuring energy expenditure while simultaneously...Grémillet, David; Lescroël, Amelie; Ballard, Grant; Dugger, Katie M.; Massaro, Melanie; Porzig, Elizabeth L.; Ainley, David G.
Enhancing quantitative approaches for assessing community resilience
Scholars from many different intellectual disciplines have attempted to measure, estimate, or quantify resilience. However, there is growing concern that lack of clarity on the operationalization of the concept will limit its application. In this paper, we discuss the theory, research development and quantitative approaches in ecological and...Chuang, W. C.; Garmestani, A.S.; Eason, T. N.; Spanbauer, T. L.; Fried-Peterson, H. B.; Roberts, C.P.; Sundstrom, Shana M.; Burnett, J.L.; Angeler, David G.; Chaffin, Brian C.; Gunderson, L.; Twidwell, Dirac; Allen, Craig R.
Fight and air exposure times of caught and released salmonids from the South Fork Snake River
Catch-and-release regulations are among the most common types of fishing regulations. In recent years, concerns have arisen regarding the exposure of fish to air during catch-and-release angling. The purpose of our study was to quantify the length of time angled fish were exposed to air by anglers in a typical catch-and-release fishery and relate...Roth, Curtis J.; Schill, Daniel J.; Quist, Michael C.
Fitting N-mixture models to count data with unmodeled heterogeneity: Bias, diagnostics, and alternative approaches
Monitoring animal populations is central to wildlife and fisheries management, and the use of N-mixture models toward these efforts has markedly increased in recent years. Nevertheless, relatively little work has evaluated estimator performance when basic assumptions are violated. Moreover, diagnostics to identify when bias in parameter estimates...Duarte, Adam; Adams, Michael J.; Peterson, James T.
Landscape assessment of side channel plugs and associated cumulative side channel attrition across a large river floodplain
Determining the influences of anthropogenic perturbations on side channel dynamics in large rivers is important from both assessment and monitoring perspectives because side channels provide critical habitat to numerous aquatic species. Side channel extents are decreasing in large rivers worldwide. Although riprap and other linear structures have...Reinhold, Ann Marie; Poole, Geoffrey C.; Bramblett, Robert G.; Zale, Alexander V.; Roberts, David W.
Quantifying salinity and season effects on eastern oyster clearance and oxygen consumption rates
There are few data on Crassostrea virginica physiological rates across the range of salinities and temperatures to which they are regularly exposed, and this limits the applicability of growth and production models using these data. The objectives of this study were to quantify, in winter (17 °C) and summer (27 °C), the...Casas, S.M.; Lavaud, Romain; LaPeyre, Megan K.; Comeau, L. A.; Filgueira, R.; LaPeyre, Jerome F.
Quantifying temporal trends in fisheries abundance using Bayesian dynamic linear models: A case study of riverine Smallmouth Bass populations
Detecting temporal changes in fish abundance is an essential component of fisheries management. Because of the need to understand short‐term and nonlinear changes in fish abundance, traditional linear models may not provide adequate information for management decisions. This study highlights the utility of Bayesian dynamic linear models (DLMs) as...Schall, Megan K.; Blazer, Vicki S.; Lorantas, Robert M.; Smith, Geoffrey; Mullican, John E.; Keplinger, Brandon J.; Wagner, Tyler
Reduced arctic tundra productivity linked with landform and climate change interactions
Arctic tundra ecosystems have experienced unprecedented change associated with climate warming over recent decades. Across the Pan-Arctic, vegetation productivity and surface greenness have trended positively over the period of satellite observation. However, since 2011 these trends have slowed considerably, showing signs of browning in many...Lara, Mark J.; Nitze, Ingmar; Grosse, Guido; Martin, Philip; McGuire, A. David
Response of moose to a high‐density road network
Road networks and the disturbance associated with vehicle traffic alter animal behavior, movements, and habitat selection. The response of moose (Alces americanus) to roads has been documented in relatively rural areas, but less is known about moose response to roads in more highly roaded landscapes. We examined road‐crossing frequencies and...Wattles, David W.; Zeller, Katherine A.; DeStefano, Stephen
Risky behavior and its effect on survival: snowshoe hare behavior under varying moonlight conditions
Predation and predation risk can exert strong influences on the behavior of prey species. However, risk avoidance behaviors may vary among populations of the same species. We studied a population of snowshoe hares (Lepus americanus) near the southern edge of their range, in Pennsylvania. This population occupies different habitat types,...Gigliotti, Laura C.; Diefenbach, Duane R.
Seasonal food habits of introduced blue catfish in Lake Oconee, Georgia
Blue catfish (Ictalurus furcatus) are native to the Coosa River drainage in northwest Georgia but have been widely introduced outside of this range including Lake Oconee, a 7677-ha impoundment on the Oconee River in central Georgia. Blue catfish abundance and growth rates have increased dramatically since their introduction in Lake Oconee, but...Jennings, Cecil A.; Mitchell, Geoffrey E.; Nelson, Chris