Skip to main content
U.S. flag

An official website of the United States government

Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9969

Investigating seagrass in Toxoplasma gondii transmission in Florida (Trichechus manatus latirostris) and Antillean (T. m. manatus) manatees

Toxoplasma gondii is a feline protozoan reported to cause morbidity and mortality in manatees and other marine mammals. Given the herbivorous nature of manatees, ingestion of oocysts from contaminated water or seagrass is presumed to be their primary mode of infection. The objectives of this study were to investigate oocyst contamination of seagrass beds in Puerto Rico and determine the seropreval
Authors
Heidi M. Wyrosdick, Richard W. Gerhold, Chunlei Su, Antonio A. Mignucci-Giannoni, Robert K. Bonde, Alycia Chapman, Carla Riviera-Perez, Jessica Martinez, Debra L. Miller

Effects of host injury on susceptibility of marine reef fishes to ectoparasitic gnathiid isopods

The importance of the role that parasites play in ecological communities is becoming increasingly apparent. However much about their impact on hosts and thus populations and communities remains poorly understood. A common observation in wild populations is high variation in levels of parasite infestation among hosts. While high variation could be due to chance encounter, there is increasing eviden
Authors
William G. Jenkins, Amanda W.J. Demopoulos, Paul C. Sikkel

Field practices: Assessing tiger population dynamics using photographic captures

From these histories, capture frequency statistics and estimates of capture probabilities can be derived.
Authors
K. Ullas Karanth, James D. Nichols, Abishek Harihar, Dale Miquelle, N. Samba Kumar, Robert Dorazio

Concepts and practices: Estimating abundance of prey species using hierarchical model-based approaches

Tigers predominantly prey on large ungulate species, such as sambar (Cervus unicolor), red deer (Cervus elaphus), gaur (Bos gaurus), banteng (Bos javanicus), chital (Axis axis), muntjac (Muntiacus muntjak), wild pig (Sus scrofa), and bearded pig (Sus barbatus). The density of a tiger population is strongly correlated with the density of such prey species (Karanth et al. 2004). In the absence of di
Authors
Robert Dorazio, N. Samba Kumar, Andy Royle, Arjun M. Gopalaswamy

A seasonal and spatial comparison of metals, and stable carbon and nitrogen isotopes, in Chincoteague Bay and the marsh deposits of Assateague Island and the adjacent vicinity, Maryland and Virginia

After Hurricane Sandy, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy overwash surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014. Surplus surface sediment was analyzed for metals, percent carbon
Authors
Alisha M. Ellis, Christopher G. Smith

Distribution of foraminifera in Chincoteague Bay and the marshes of Assateague Island and the adjacent vicinity, Maryland and Virginia

Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy washover surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014, after Hurricane Sandy. Micropaleontology samples were collected as part of a comp
Authors
Alisha M. Ellis, Jaimie Shaw, Lisa E. Osterman, Christopher G. Smith

Characterizing storm response and recovery using the beach change envelope: Fire Island, New York

Hurricane Sandy at Fire Island, New York presented unique challenges in the quantification of storm impacts using traditional metrics of coastal change, wherein measured changes (shoreline, dune crest, and volume change) did not fully reflect the substantial changes in sediment redistribution following the storm. We used a time series of beach profile data at Fire Island, New York to define a new
Authors
Owen T. Brenner, Erika Lentz, Cheryl J. Hapke, Rachel Henderson, Kathleen Wilson, Timothy Nelson

Estimating virus occurrence using Bayesian modeling in multiple drinking water systems of the United States

Drinking water treatment plants rely on purification of contaminated source waters to provide communities with potable water. One group of possible contaminants are enteric viruses. Measurement of viral quantities in environmental water systems are often performed using polymerase chain reaction (PCR) or quantitative PCR (qPCR). However, true values may be underestimated due to challenges involved
Authors
Eunice A. Varughese, Nichole E Brinkman, Emily M Anneken, Jennifer S Cashdollar, G. Shay Fout, Edward T. Furlong, Dana W. Kolpin, Susan T. Glassmeyer, Scott P Keely

Concepts: Integrating population survey data from different spatial scales, sampling methods, and species

Conservationists and managers are continually under pressure from the public, the media, and political policy makers to provide “tiger numbers,” not just for protected reserves, but also for large spatial scales, including landscapes, regions, states, nations, and even globally. Estimating the abundance of tigers within relatively small areas (e.g., protected reserves) is becoming increasingly tra
Authors
Robert Dorazio, Mohan Delampady, Soumen Dey, Arjun M. Gopalaswamy

Advancing mangrove macroecology

Mangrove forests provide a wide range of ecosystem services to society, yet they are among the most anthropogenically impacted coastal ecosystems in the world. In this chapter, we discuss and provide examples for how macroecology can advance our understanding of mangrove ecosystems. Macroecology is broadly defined as a discipline that uses statistical analyses to investigate large-scale, universal
Authors
Victor H. Rivera-Monroy, Michael J. Osland, John W. Day, Santanu Ray, Andre S. Rovai, Richard H. Day, Joyita Mukherjee

Estimating discharge and nonpoint source nitrate loading to streams from three end‐member pathways using high‐frequency water quality data

The myriad hydrologic and biogeochemical processes taking place in watersheds occurring across space and time are integrated and reflected in the quantity and quality of water in streams and rivers. Collection of high‐frequency water quality data with sensors in surface waters provides new opportunities to disentangle these processes and quantify sources and transport of water and solutes in the c
Authors
Matthew P. Miller, Anthony J. Tesoriero, Krista Hood, Silvia Terziotti, David M. Wolock

Timing of warm water refuge use in Crystal River National Wildlife Refuge by manatees—Results and insights from Global Positioning System telemetry data

Managers at the U.S. Fish and Wildlife Service Crystal River National Wildlife Refuge (CRNWR) desire to update their management plan regarding the operation of select springs including Three Sisters Springs. They wish to refine existing parameters used to predict the presence of federally threatened Trichechus manatus latirostris (Florida manatee) in the springs and thereby improve their manatee m
Authors
Daniel H. Slone, Susan M. Butler, James P. Reid, Catherine G. Haase