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Find out more about Biological Threat and Invasive Species Research through our publications.

Filter Total Items: 308

Characteristics for the external identification of Black Carp from Grass Carp

Black Carp Mylopharyngodon piceus and Grass Carp Ctenopharyngodon idella are morphologically similar species native to eastern Asia and imported to North America as biological control organisms. Preferred identification methods are coloration and pharyngeal tooth form. Grass Carp possess serrated teeth and Black Carp molariform teeth. Examination of pharyngeal teeth causes extensive damage to a sp
Authors
Patrick Kroboth, Duane Chapman, Robert A. Hrabik, D.A. Neely

The ecology of chronic wasting disease in wildlife

Prions are misfolded infectious proteins responsible for a group of fatal neurodegenerative diseases termed transmissible spongiform encephalopathy or prion diseases. Chronic Wasting Disease (CWD) is the prion disease with the highest spillover potential, affecting at least seven Cervidae (deer) species. The zoonotic potential of CWD is inconclusive and cannot be ruled out. A risk of infection for
Authors
Luis E. Escobar, Sandra Pritzkow, Steven N Winter, Daniel A. Grear, Megan S. Kirchgessner, Ernesto Dominguez-Villegas, Gustavo Machado, A Townsend Peterson, Claudio Soto

Serum iron analytes in healthy and diseased Florida manatees (Trichechus manatus latirostris)

Serum iron concentration is usually decreased in true iron deficiency and with inflammatory disease in man and domestic animals. Serum total iron binding capacity (TIBC) may be increased in true iron deficiency and decreased with inflammatory disease. This prospective study was designed to measure serum iron analytes in healthy free-ranging and housed Florida manatees (Trichechus manatus latirostr
Authors
John W. Harvey, Kendal E Harr, David Murphy, Michael T. Walsh, Martine deWit, Charles J. Deutsch, Robert Bonde

Relationships between soil macroinvertebrates and nonnative feral pigs (Sus scrofa) in Hawaiian tropical montane wet forests

Nonnative feral pigs (Sus scrofa) are recognized throughout the New World as a highly significant introduced species in terms of ecosystem alteration. Similarly, nonnative soil macroinvertebrates (e.g. earthworms, ground beetles) invade and alter the structure and function of native habitats globally. However, the relationship between feral pigs and soil macroinvertebrates remains largely unknown.
Authors
Nathaniel H. Wehr, Creighton M Litton, Noa K Lincoln, Steve C. Hess

Caryospora-like coccidia infecting green turtles (Chelonia mydas): An emerging disease with evidence of interoceanic dissemination

Protozoa morphologically consistent with Caryospora sp. are one of the few pathogens associated with episodic mass mortality events involving free-ranging sea turtles. Parasitism of green turtles (Chelonia mydas) by these coccidia and associated mortality was first reported in maricultured turtles in the Caribbean during the 1970s. Years later, epizootics affecting wild green turtles in Australia
Authors
Brian A. Stacy, Phoebe A. Chapman, Heather Stockdale-Walden, Thierry M. Work, Julie Dagenais, Allen M. Foley, Morgan Wideroff, Jr. Wellehan, April L. Childress, Charles A. Manire, Mya Rodriguez, Trevor T. Zachariah, Lydia Staggs, Bette Zirkelbach, Nina Nahvi, Whitney Crowder, Shane M. Boylan, Shelly Marquardt, Craig Pelton, Terry M. Norton

Genomic pedigree reconstruction identifies predictors of mating and reproductive success in an invasive vertebrate

The persistence of an invasive species is influenced by its reproductive ecology, and a successful control program must operate on this premise. However, the reproductive ecology of invasive species may be enigmatic due to factors that also limit their management, such as cryptic coloration and behavior. We explored the mating and reproductive ecology of the invasive Brown Treesnake (BTS: Boiga ir
Authors
Brenna A Levine, Marlis R Douglas, Amy A. Yackel Adams, Bjorn Lardner, Robert Reed, Julie A. Savidge, Michael E Douglas

Optimizing walking pace to maximize snake detection rate: A visual encounter survey experiment

Visual encounter survey efforts can be defined and constrained by duration, distance, or both duration and distance simultaneously. This study examines the optimal walking pace that will maximize the number of animal detections within a limited time frame. We predicted that animal sighting rate per unit of distance would decline with increasing pace, but that maximal sighting rate per unit of time
Authors
Bjorn Lardner, Amy A. Yackel Adams, Julie A. Savidge, Robert Reed

Black Carp in North America: A description of range, habitats, time of year, and methods of reported captures

Black Carp Mylopharyngodon piceus are considered invasive in North America. Since the first wild capture in 2003, collection records have increased, yet information summarizing successful collection methods is lacking. Reported capture methods throughout the Black Carp's native and introduced ranges vary providing minimal aid for determining control and monitoring methods. Here, we describe the cu
Authors
Patrick Kroboth, Cortney Cox, Duane Chapman, Gregory W. Whitledge

The nucleoprotein and phosphoprotein are major determinants of the virulence of viral hemorrhagic septicemia virus in rainbow trout

Viral hemorrhagic septicemia virus (VHSV), a fish rhabdovirus, infects several marine and freshwater fish species. There are many strains of VHSV that affect different fish, but some strains of one genetic subgroup have gained high virulence in rainbow trout (Oncorhynchus mykiss). To define the genetic basis of high virulence in trout, we used reverse genetics to create chimeric VHSVs in which vir
Authors
Vikram N Vakharia, Jie Liu, Douglas Mckenney, Gael Kurath

U.S. Geological Survey response to chronic wasting disease

The U.S. Geological Survey (USGS) is focused on the development of early detection and effective response tools that promote an adaptive management approach to chronic wasting disease (CWD). USGS scientists across the United States are working to understand the biology of CWD, assess and predict the spread and persistence in wildlife and the environment, and develop tools for early detection and c
Authors
M. Camille Hopkins, Suzanna C. Soileau

Towards recovery of an endangered island endemic: Distributional and behavioral responses of Key Largo woodrats associated with exotic predator removal

Exotic predators create novel ecological contexts for native species, particularly when prey exhibit predator naïve behaviors. Population recovery of island endemic species following predator eradication has been documented broadly, but studies examining mammalian prey behavioral responses to exotic predator removal are less common. The Key Largo woodrat (Neotoma floridana smalli) is an endangered
Authors
Michael V. Cove, Theodore Simons, Beth Gardner, Allan F. O'Connell

Contact rates with nesting birds before and after invasive snake removal: Estimating the effects of trap-based control

Invasive predators are responsible for almost 60% of all vertebrate extinctions worldwide with the most vulnerable faunas occurring on islands. The brown treesnake (Boiga irregularis) is a notorious invasive predator that caused the extirpation or extinction of most native forest birds on Guam. The success of avian reintroduction efforts on Guam will depend on whether snake-control techniques suff
Authors
Amy A. Yackel Adams, Melia G. Nafus, Page Klug, Bjorn Lardner, M.J. Mazurek, Julie A. Savidge, Robert Reed