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A three-dimensional Lagrangian particle tracking model for predicting transport of eggs of rheophilic-spawning carps in turbulent rivers A three-dimensional Lagrangian particle tracking model for predicting transport of eggs of rheophilic-spawning carps in turbulent rivers
Grass carp, bighead carp, and silver carp spawn in flowing water. Their eggs, and then larvae, develop while drifting. Hydraulic conditions and water temperature control spawning locations, egg survival, and the downstream distance traveled before the hatched larvae can swim for low velocity nursery habitats. Existing egg drift models simulate the fluvial transport of carp eggs but have
Authors
Geng Li, Bin Wang, Caroline M. Elliott, Bruce Call, Duane Chapman, R. B. Jacobson
Multi-stage soil-hydraulic recovery and limited ravel accumulations following the 2017 Nuns and Tubbs wildfires in Northern California Multi-stage soil-hydraulic recovery and limited ravel accumulations following the 2017 Nuns and Tubbs wildfires in Northern California
Wildfire can impact soil-hydraulic properties by reducing saturated hydraulic conductivity and sorptivity, making recently burned landscapes prone to debris flows and flash floods. The post-fire hazard window can range from years to decades. In Northern California, where wildfire frequency is steadily increasing, the impact and soil-hydraulic recovery from wildfires is unknown. Following...
Authors
Jonathan P. Perkins, Carlos Diaz, Skye C. Corbett, Corina Cerovski-Darriau, Jonathan D. Stock, Jeffrey Paul Prancevic, Lisa Micheli, Jay Jasperse
Petrogenesis and rare earth element mineralization of the Elk Creek carbonatite, Nebraska, USA Petrogenesis and rare earth element mineralization of the Elk Creek carbonatite, Nebraska, USA
Although carbonatites are the primary source of the world’s rare earth elements (REEs), the processes responsible for ore-grade REE enrichment in carbonatites are still poorly understood. In this study, we present a petrologic, geochemical, and isotopic evaluation of the Elk Creek carbonatite in southeast Nebraska to constrain the origin of REE mineralization. The Elk Creek carbonatite...
Authors
Philip Verplanck, G. Lang Farmer, Richard M. Kettler, Heather A. Lowers, Craig A. Johnson, Alan E. Koenig, Michael J. Blessington
Breeding dynamics of gopher frog metapopulations over 10 years Breeding dynamics of gopher frog metapopulations over 10 years
Populations of amphibians that breed in isolated, ephemeral wetlands may be particularly sensitive to breeding and recruitment rates, which can be influenced by dynamic and difficult-to-predict extrinsic factors. The gopher frog Rana capito is a declining species currently proposed for listing under the U.S. Endangered Species Act, as well as one of many pond-breeding amphibians of...
Authors
Brian A. Crawford, Anna L. Farmer, Kevin M Enge, Aubrey Heupel Greene, Lauren Diaz, John C. Maerz, Clinton T. Moore
Biogeography of freshwater mussels (Bivalvia: Unionida) in Texas and implications on conservation biology Biogeography of freshwater mussels (Bivalvia: Unionida) in Texas and implications on conservation biology
Aim Biogeography seeks to identify and explain the spatial distributions of species and has become an important tool used by conservationists to protect and manage aquatic organisms. Texas, located in the southwestern United States, is home to 52 species of freshwater mussels, 9 of which are endemic to Texas and 7 that are endemic to Texas and neighboring states or countries. There have...
Authors
Michael de Moulpied, Chase H. Smith, Clint R. Robertson, Nathan Johnson, Roel Lopez, Charles R. Randklev
Structured decision making to rank North American Wetland Conservation Act proposals within joint venture regions Structured decision making to rank North American Wetland Conservation Act proposals within joint venture regions
The North American Wetlands Conservation Act (16 U.S.C. 4401-4412) provided funding and administration for wetland management and conservation projects. The North American Wetland Conservation Fund, enabled in 1989 with the Act, provides financial resources. Resource allocation decisions are based, in part, on regional experts, particularly migratory bird Joint Ventures (JVs) (i.e...
Authors
Anastasia Krainyk, James E. Lyons, Gregory J. Soulliere, John M. Coluccy, Barry C. Wilson, Michael G. Brasher, Mohammed A Al-Saffar, Dale D. Humburg
Can coastal habitats rise to the challenge? Resilience of estuarine habitats, carbon accumulation, and economic value to sea-level rise in a Puget Sound estuary Can coastal habitats rise to the challenge? Resilience of estuarine habitats, carbon accumulation, and economic value to sea-level rise in a Puget Sound estuary
Sea-level rise (SLR) and obstructions to sediment delivery pose challenges to the persistence of estuarine habitats and the ecosystem services they provide. Restoration actions and sediment management strategies may help mitigate such challenges by encouraging the vertical accretion of sediment in and horizontal migration of tidal forests and marshes. We used a process-based soil...
Authors
Monica Mei Jeen Moritsch, Kristin B. Byrd, Melanie J. Davis, Anthony J. Good, Judith Z. Drexler, James T. Morris, Isa Woo, Lisamarie Windham-Myers, Eric E. Grossman, Glynnis Nakai, Katrina L. Poppe, John M. Rybczyk
Quantifying the effects of tides, river flow, and barriers on movements of Chinook Salmon smolts at junctions in the Sacramento–San Joaquin River Delta using multistate models Quantifying the effects of tides, river flow, and barriers on movements of Chinook Salmon smolts at junctions in the Sacramento–San Joaquin River Delta using multistate models
Successful migration of Chinook Salmon (Oncorhynchus tshawytscha) smolts seaward in the Sacramento – San Joaquin River Delta (hereafter, Delta) requires navigating a network of numerous branching channels. Within the Delta, several key junctions route smolts either towards more direct paths to the ocean or towards the interior Delta, an area associated with decreased survival. Movements...
Authors
Michael J. Dodrill, Russell Perry, Adam C. Pope, Xiaochun Wang
Dynamic sensitivity to resource availability influences population responses to mismatches in a shorebird Dynamic sensitivity to resource availability influences population responses to mismatches in a shorebird
Climate change has caused shifts in seasonally recurring biological events leading to the temporal decoupling of consumer-resource pairs – i.e., phenological mismatching. Although mismatches often affect individual fitness, they do not invariably scale up to affect populations, making it difficult to assess the risk they pose. Individual variation may contribute to this inconsistency...
Authors
Luke R. Wilde, Josiah E. Simmons, Rose J. Swift, Nathan R. Senner
A look ahead to the next decade at US volcano observatories A look ahead to the next decade at US volcano observatories
Volcano monitoring, eruption response, and hazard assessment at volcanoes in the United States of America (US) fall under the mandate of five regional volcano observatories covering 161 active volcanoes. Working in a wide range of volcanic and geographic settings, US observatories must learn from and apply new knowledge and techniques to a great variety of scientific and hazard...
Authors
Hannah R. Dietterich, Christina A. Neal
Taking the leap: A binational translocation effort to close the 420-km gap in the Baja California lineage of the California red-legged frog (Rana draytonii) Taking the leap: A binational translocation effort to close the 420-km gap in the Baja California lineage of the California red-legged frog (Rana draytonii)
Conservation translocations, the human-mediated movement and release of a living organism for a conservation benefit, are increasingly recommended in species’ recovery plans as a technique for mitigating population declines or augmenting genetic diversity. However, translocation protocols for species with broad distributions may require regionally specific considerations to increase...
Authors
Susan North, Jonathan Q. Richmond, Frank E. Santana, Anny Peralta-García, Elizabeth Gallegos, Adam R. Backlin, Cynthia Joan Hitchcock, Bradford Hollingsworth, Jorge H. Valdez-Villavicencio, Zachary Principe, Robert N. Fisher, Clark S. Winchell
Chew-cards can accurately index invasive rat densities in Mariana Island forests Chew-cards can accurately index invasive rat densities in Mariana Island forests
Rats (Rattus spp.) are likely established on 80–90% of the world’s islands and represent one of the most damaging and expensive biological invaders. Effective rat control tools exist but require accurate population density estimates or indices to inform treatment timing and effort and to assess treatment efficacy. Capture-mark-recapture data are frequently used to produce robust density...
Authors
Emma B. Hanslowe, Amy A. Yackel Adams, Melia Gail Nafus, Douglas A Page, Danielle R. Bradke, Francesca T. Erickson, Larissa L. Bailey