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: 42765
Cyanotoxin mixture models: Relating environmental variables and toxin co-occurrence to human exposure risk Cyanotoxin mixture models: Relating environmental variables and toxin co-occurrence to human exposure risk
Toxic cyanobacterial blooms, often containing multiple toxins, are a serious public health issue. However, there are no known models that predict a cyanotoxin mixture (anatoxin-a, microcystin, saxitoxin). This paper presents two cyanotoxin mixture models (MIX) and compares them to two microcystin (MC) models from data collected in 2016–2017 from three recurring cyanobacterial bloom...
Authors
Victoria Christensen, Erin A. Stelzer, Barbara C. Scudder Eikenberry, Hayley T. Olds, Jaime F. LeDuc, Ryan P. Maki, Jack E. Norland, Eakalak Khan
Population density, distribution, and trends of landbirds in the National Park of American Samoa, Ta‘ū and Tutuila Units (2011–2018) Population density, distribution, and trends of landbirds in the National Park of American Samoa, Ta‘ū and Tutuila Units (2011–2018)
The National Park of American Samoa (NPSA) was surveyed for landbirds from June through July, 2018. Surveys were conducted using point-transect distance sampling methods to estimate bird densities. This information provides the second datum in the time-series of landbird monitoring for long-term trends in landbird distribution, density, and abundance within NPSA. The Ta‘ū Unit and...
Authors
Seth Judge, Richard J. Camp, Visa Vaivai, Patrick J. Hart
Trophic ecology Trophic ecology
The trophic ecology of lake charr Salvelinus namaycush morphotypes from small and large lakes within their native and introduced ranges is reviewed over the past 50 years. The lake charr is an apex predator in most habitats it occupies, where it plays a significant role in defining food webs. While often considered piscivores, lake charr feed on a range of aquatic prey throughout their...
Authors
Mark Vinson, Louise Chavarie, Caroline Lynn Rosinski, Heidi K. Swanson
Distribution Distribution
The lake charr Salvelinus namaycush is restricted in its native distribution to oligotrophic fresh waters of northern North America largely within the extent of the Pleistocene glaciations. It is the only freshwater species in northwest North America that does not occur in Siberia. A GIS-based native occurrence map linked to the HydroLAKES database does not extend the lake charr range...
Authors
Andrew M. Muir, David Bennion, Michael J Hansen, Stephen Riley, John Gunn
Reproduction Reproduction
Lake charr Salvelinus namaycush are typically fall spawners although one ecotype has populations that spawn during spring and fall (siscowets in Lake Superior). Lake charr are iteroparous (reproduce more than once in a lifetime) with group-synchronous ovarian development and typically spawn once per year. However, lake charr may not reproduce every year, a phenomenon known as skipped...
Authors
Frederick W. Goetz, J. Ellen Marsden, Catherine A. Richter, Donald E. Tillitt, Shawn P. Sitar, Stephen Riley, Charles C. Krueger
Monitoring Tamarix changes using WorldView-2 satellite imagery in Grand Canyon National Park, Arizona Monitoring Tamarix changes using WorldView-2 satellite imagery in Grand Canyon National Park, Arizona
Remote sensing methods are commonly used to monitor the invasive riparian shrub tamarisk (Tamarix spp.) and its response to the northern tamarisk beetle (D. carinulata), a specialized herbivore introduced as a biocontrol agent to control tamarisk in the Southwest USA in 2001. We use a Spectral Angle Mapper (SAM) supervised classification method with WorldView-2 (2 m spatial resolution)
Authors
Nathaniel D. Bransky, Temuulen T. Sankey, Joel B. Sankey, Matthew D. Johnson, Levi R. Jamison
Response to ‘Stochastic and deterministic interpretation of pool models’ Response to ‘Stochastic and deterministic interpretation of pool models’
We concur with Azizi‐Rad et al. (2021) that it is vital to critically evaluate and compare different soil carbon models, and we welcome the opportunity to further describe the unique contribution of the PROMISE model (Waring et al. 2020) to this literature. The PROMISE framework does share many features with established biogeochemical models, as our original manuscript highlighted in...
Authors
Bonnie G. Waring, Benjamin N. Sulman, Sasha C. Reed, A. Peyton Smith, Colin Averill, Courtney Creamer, Daniela F. Cusack, Steven J. Hall, Julie D. Jastrow, Andrea Jilling, Kenneth M. Kemner, Markus Kleber, Xiao-Jun Allen Liu, Jennifer Pett-Ridge, Marjorie S. Schulz
The enigma of the Předmostí protodogs. A comment on Prassack et al. 2020 The enigma of the Předmostí protodogs. A comment on Prassack et al. 2020
Prassack et al. (2020) analyzed dental microwear in a sample of canids from the Gravettian site of Předmostí that had been identified as either Paleolithic dogs or Pleistocene wolves (n = 10 in each group), accepting that the morphological differences between the groups validly distinguished the (self-domesticating) protodogs from wolves. The authors then concluded that differences in...
Authors
Luc A. A. Janssens, Myriam Boudadi-Maligne, L. David Mech, Dennis Lawler
Greenhouse gas emissions from an arid-zone reservoir and their environmental policy significance: Results from existing global models and an exploratory dataset Greenhouse gas emissions from an arid-zone reservoir and their environmental policy significance: Results from existing global models and an exploratory dataset
Reservoirs in arid regions often provide critical water storage but little is known about their greenhouse gas (GHG) footprint. While there is growing appreciation of the role reservoirs play as GHG sources, there is a lack of understanding of GHG emission dynamics from reservoirs in arid regions and implications for environmental policy. Here we present initial GHG emission measurements...
Authors
Sarah Waldo, Bridget Deemer, Lucas S. Bair, Jake J. Beaulieu
The tide turns: Episodic and localized cross-contamination of a California coastline with cyanotoxins The tide turns: Episodic and localized cross-contamination of a California coastline with cyanotoxins
The contamination of coastal ecosystems from a variety of toxins of marine algal origin is a common and well-documented situation along the coasts of the United States and globally. The occurrence of toxins originating from cyanobacteria along marine coastlines is much less studied, and little information exists on whether toxins from marine and freshwater sources co-occur regularly. The...
Authors
Avery O. Tatters, Jayme Smith, Raphael M. Kudela, Kendra Hayashi, Meredith D. A. Howard, Ariel Donovan, Keith A. Loftin, David A. Caron
Stationary hydroacoustics demonstrates vessel avoidance biases during mobile hydroacoustic surveys of alewife in Lake Ontario Stationary hydroacoustics demonstrates vessel avoidance biases during mobile hydroacoustic surveys of alewife in Lake Ontario
Mobile hydroacoustic surveys are routinely used to estimate pelagic fish abundance. In the Great Lakes, alewife are commonly surveyed with mobile hydroacoustics, however, their behavior often has them associated with epilimnetic habitats which increases the potential for vessel avoidance to bias hydroacoustic observations. Abundance estimates from mobile hydroacoustic surveys are...
Authors
Conner Elliot, Jeremy Holden, Michael Connerton, Brian Weidel, Bruce Tufts
When introduced prey violates trophic hierarchy: Conservation of an endangered predator When introduced prey violates trophic hierarchy: Conservation of an endangered predator
Introduced species often disrupt established food webs, but some native predators can come to rely on introduced prey. Understanding the net effects of the non-natives on imperiled predators is crucial for planning conservation measures. The invasive American bullfrog (Lithobates catesbeianus) can be prey, predator, and competitor for the critically endangered San Francisco garter snake
Authors
Richard Kim, Brian J. Halstead, Eric J. Routman, Julie Anderson