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Publications

This list of publications includes peer-review journal articles, official USGS publications series, reports and more authored by scientists in the Ecosystems Mission Area. A database of all USGS publications, with advanced search features, can be accessed at the USGS Publications Warehouse.  

Filter Total Items: 41758

Ooencyrtus pitosina (Hymenoptera: Encyrtidae)–A natural enemy of Samoan swallowtail butterfly Papilio godeffroyi (Lepidoptera: Papilionidae)

A new species of encyrtid wasp, Ooencyrtus pitosina Polaszek, Noyes & Fusu sp. n., (Hymenoptera: Encyrtidae: Encyrtinae) is described as a gregarious parasitoid in the eggs of the endemic Samoan swallowtail butterfly Papilio godeffroyi (Lepidoptera: Papilionidae) in the Samoan archipelago. It is described here because it is an important natural enemy of this butterfly, and to facilitate identifica
Authors
Andrew Polaszek, John Noyes, Elena Lugli, Mark Schmaedick, Robert W. Peck, Paul C. Banko, Lucian Fusu

Application of the technology readiness levels framework to natural resource management tools

Technology advancements in fisheries science can provide useful tools to support natural resource management and conservation. However, new technologies may also present challenges for decision makers due to the lack of a standardized process to assess technologies for consideration within management plans. Future technology development in fishery and water resources could benefit from a framework
Authors
Aaron R. Cupp, Andrea K. Fritts, Marybeth K. Brey, Christa M. Woodley, David Smith, Mark Cornish, Amy McGovern, Rob Simmonds, Neal Jackson

Visitation to national parks in California shows annual and seasonal change during extreme drought and wet years

This study examines the influence of drought indicators on recreational visitation patterns to National Park Service units in California (USA) from 1980 to 2019. We considered mountain, arid, and coastal park types across a climate gradient where seasonal recreational opportunities are directly or indirectly dependent on water resources. Significant departures from the normal hydroclimate, reflect
Authors
Jeffrey S. Jenkins, John T. Abatzoglou, Emily J. Wilkins, Elizabeth E. Perry

Bighorn sheep associations: Understanding tradeoffs of sociality and implications for disease transmission

Sociality directly influences mating success, survival rates, and disease, but ultimately likely evolved for its fitness benefits in a challenging environment. The tradeoffs between the costs and benefits of sociality can operate at multiple scales, resulting in different interpretations of animal behavior. We investigated the influence of intrinsic (e.g., relatedness, age) and extrinsic factors (
Authors
Marie Tosa, Mark Biel, Tabitha A. Graves

Evolutionary fire ecology: An historical account and future directions

The idea that fire acts as an evolutionary force contributing to shaping species traits started a century ago, but had not been widely recognized until very recently. Among the first to realize this force were Edward B. Poulton, R. Dale Guthrie, and Edwin V. Komarek in animals and Willis L. Jepson, Walter W. Hough, Tom M. Harris, Philip V. Wells, and Robert W. Mutch in plants. They were all ahead
Authors
Juli G. Pausas, Jon Keeley

Fuel treatments in shrublands experiencing pinyon and juniper expansion result in trade-offs between desired vegetation and increased fire behavior

BackgroundNative pinyon (Pinus spp.) and juniper (Juniperus spp.) trees are expanding into shrubland communities across the Western United States. These trees often outcompete with native sagebrush (Artemisia spp.) associated species, resulting in increased canopy fuels and reduced surface fuels. Woodland expansion often results in longer fire return intervals with potential for high severity crow
Authors
Claire L. Williams, Lisa M. Ellsworth, Eva Strand, Matt C. Reeves, Scott Shaff, Karen Short, Jeanne C. Chambers, Beth Newingham, Claire Tortorelli

Variation in flight characteristics associated with entry by eagles into rotor-swept zones of wind turbines

Automated curtailment of wind turbines can reduce fatality rates of wildlife, but the resulting increased number of curtailments can reduce power generation. Tailoring curtailment criteria for each individual turbine could reduce unnecessary curtailment, yet it is unknown whether the risk to wildlife varies among turbines. We demonstrate turbine-specific variation in the speed, altitude, approach
Authors
Brian W. Rolek, Melissa A. Braham, Tricia A. Miller, Adam E. Duerr, Todd E. Katzner, Christopher J W McClure

Why are larger fish farther upstream? Testing multiple hypotheses using Silver Chub in two Midwestern United States riverscapes

ObjectiveThree competing hypotheses might explain the widely documented intrapopulation larger-fish-upstream phenomenon. The age-phased recruitment hypothesis posits that fish spawn downstream and move upstream as they age and grow, the static population with growth and mortality gradients hypothesis posits that fish spawn throughout a riverscape and growth is greater upstream while recruitment is
Authors
Joshuah S. Perkin, Patrick M. Kočovský, Zachary D Steffensmeier, Keith B. Gido

A spatially explicit modeling framework to guide management of subsidized avian predator densities

Anthropogenic resource subsidization across western ecosystems has contributed to widespread increases in generalist avian predators, including common ravens (Corvus corax; hereafter, raven). Ravens are adept nest predators and can negatively impact species of conservation concern. Predation effects from ravens are especially concerning for greater sage-grouse (Centrocercus urophasianus; hereafter
Authors
Shawn T. O'Neil, Peter S. Coates, Sarah C. Webster, Brianne E. Brussee, Seth J. Dettenmaier, John C. Tull, Pat J. Jackson, Michael L. Casazza, Shawn P. Espinosa

Spatial and temporal overlap between hatchery- and natural-origin steelhead and Chinook salmon during spawning in the Klickitat River, Washington, USA

A goal of many segregated salmonid hatchery programs is to minimize potential interbreeding between hatchery- and natural-origin fish. To assess this on the Klickitat River, Washington, USA, we used radiotelemetry during 2009–2014 to evaluate spatiotemporal spawning overlap between hatchery-origin and natural-origin steelhead Oncorhynchus mykiss and spring Chinook Salmon O. tshawytscha. We estimat
Authors
Joseph S. Zendt, Brady Allen, Tobias Kock, Russell Perry, Adam Pope

A brave new world: Managing for biodiversity conservation under ecosystem transformation

Traditional conservation practices have primarily relied on maintaining biodiversity by preserving species and habitats in place. Many regions are experiencing unprecedented environmental conditions, shifts in species distribution and habitats, and high turnover in species composition, resulting in ecological transformation. Natural resource managers have lacked tools for identifying and selecting
Authors
Jennifer L. Wilkening, Dawn Robin Magness, Laura Thompson, Abigail Lynch

Assessment of recovery potential for the American horseshoe crab (Limulus polyphemus): An application of the IUCN green status process

According to an International Union for Conservation of Nature (IUCN) Red List assessment (RLA), the American horseshoe crab (Limulus polyphemus), an iconic coastal species, is at risk of extirpation in some regions within its range where small and vulnerable populations occur. However, the RLA does not consider future status beyond viability and does not attempt to identify the conservation neces
Authors
David R. Smith, H. Jane Brockmann, Ruth H. Carmichael, Eric M. Hallerman, W.M. Watson, Jaime Zaldivar-Rae