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Reproductive endocrine disruption in smallmouth bass (Micropterus dolomieu) in the Potomac River basin: spatial and temporal comparisons of biological effects Reproductive endocrine disruption in smallmouth bass (Micropterus dolomieu) in the Potomac River basin: spatial and temporal comparisons of biological effects

A high prevalence of intersex or testicular oocytes (TO) in male smallmouth bass within the Potomac River drainage has raised concerns as to the health of the river. Studies were conducted to document biomarker responses both temporally and spatially to better understand the influence of normal physiological cycles, as well as water quality and land-use influences. Smallmouth bass were...
Authors
Vicki Blazer, Luke R. Iwanowicz, Holly Henderson, Patricia M. Mazik, Jill A. Jenkins, David A. Alvarez, John A. Young

Spectral definition of the macro-algae Ulva curvata in the back-barrier bays of the Eastern Shore of Virginia, USA Spectral definition of the macro-algae Ulva curvata in the back-barrier bays of the Eastern Shore of Virginia, USA

We have developed methods to determine the visible (VIS) to near-infrared (NIR) spectral properties of thalli and epiphytes of bloom-forming and green macrophyte Ulva curvata in back-barrier lagoons in Virginia, USA. A 2% increase in NIR thalli reflectance from winter to summer (ca. 9.5%) matched the drop in summer NIR transmittance (ca. 90%). In contrast, summer and winter VIS...
Authors
E. Ramsey, A. Rangoonwalaj, M.S. Thomsen, A. Schwarzschild

Occurrence and distribution of Asian carps in Louisiana Occurrence and distribution of Asian carps in Louisiana

In the 1970s, commercial fishers reported sightings of grass carp Ctenopharyngodon idella in large rivers and associated backwaters of Louisiana; the first specimen in Louisiana Department of Wildlife and Fisheries' fishery independent sampling was recorded in 1976. Beginning in the early 1980s, commercial fishers noted increasing populations of bighead carp Hypophthalmichthys nobilis...
Authors
R. Glenn Thomas, Jill A. Jenkins, Jody David

Hyperspectral remote sensing of wetland vegetation Hyperspectral remote sensing of wetland vegetation

Wetlands proportionally exert a higher influence on biogeochemical fluxes among the land, the atmosphere, and hydrologic systems than their 1% worldwide occurrence suggests [1]. Although their frequency of occurrence is low and their importance is high, wetlands continue to face high detrimental pressures from natural and human-induced forces [2]. Remote sensing offers the single best...
Authors
Elijah Ramsey III, Amina Rangoonwala

The American crocodile in Biscayne Bay, Florida The American crocodile in Biscayne Bay, Florida

Intensive crocodile monitoring programs conducted during the late 1970s and early 1980s in southern Florida resulted in an optimistic outlook for recovery of the protected species population. However, some areas with suitable crocodile habitat were not investigated, such as Biscayne Bay and the mainland shorelines of Barnes and Card Sounds. The objective of our study was to determine...
Authors
Michael S. Cherkiss, Stephanie S. Romañach, Frank J. Mazzotti

Mapping the Natchez Trace Parkway Mapping the Natchez Trace Parkway

Based on a National Park Service (NPS) landcover classification, a landcover map of the 715-km (444-mile) NPS Natchez Trace Parkway (hereafter referred to as the "Parkway") was created. The NPS landcover classification followed National Vegetation Classification (NVC) protocols. The landcover map, which extended the initial landcover classification to the entire Parkway, was based on...
Authors
Amina Rangoonwala, Terri Bannister, Elijah W. Ramsey

Survival, growth and reproduction of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus 1758). I. Physiological capabilities in various temperatures and salinities Survival, growth and reproduction of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus 1758). I. Physiological capabilities in various temperatures and salinities

The physiological tolerances of non-native fishes is an integral component of assessing potential invasive risk. Salinity and temperature are environmental variables that limit the spread of many non-native fishes. We hypothesised that combinations of temperature and salinity will interact to affect survival, growth, and reproduction of Nile tilapia, Oreochromis niloticus, introduced...
Authors
Pamela J. Schofield, Mark S. Peterson, Michael R. Lowe, Nancy J. Brown-Peterson, William T. Slack

Sperm quality assessments for endangered razorback suckers Xyrauchen texanus Sperm quality assessments for endangered razorback suckers Xyrauchen texanus

Flow cytometry (FCM) and computer-assisted sperm motion analysis (CASA) methods were developed and validated for use with endangered razorback suckers Xyrauchen texanus collected (n=64) during the 2006 spawning season. Sperm motility could be activated within osmolality ranges noted during milt collections (here 167–343 mOsm/kg). We hypothesized that sperm quality of milt collected into...
Authors
Jill A. Jenkins, Bruce E. Eilts, Amy M. Guitreau, Chester R. Figiel, Rassa O. Draugelis-Dale, Terrence R. Tiersch

Seroepidemiology of TmPV1 infection in captive and wild Florida manatees (Trichechus manatus latirostris) Seroepidemiology of TmPV1 infection in captive and wild Florida manatees (Trichechus manatus latirostris)

In 1997, cutaneous papillomatosis caused by Florida manatee (Trichechus manatus latirostris [Tm]) papillomavirus 1 (TmPV1) was detected in seven captive manatees at the Homosassa Springs Wildlife State Park, Florida, USA, and, subsequently, in two wild manatees from the adjacent Homosassa River. Since then, papillomatosis has been reported in captive manatees housed in other locations...
Authors
Maria Gabriella Dona, Manuela Rehtanz, Nicole M. Adimey, Gregory D. Bossart, Alfred B. Jenson, Robert K. Bonde, Shin-je Ghim

Mitigating by-catch of diamondback terrapins in crab pots Mitigating by-catch of diamondback terrapins in crab pots

Chronic by‐catch of diamondback terrapins (Malaclemys terrapin) in blue crab (Callinectes sapidus) pots is a concern for terrapin conservation along the United States Atlantic and Gulf of Mexico coasts. Despite the availability of by‐catch reduction devices (BRDs) for crab pots, adoption of BRDs has not been mandated and by‐catch of terrapins continues. We conducted experimental fishing...
Authors
Kristen M. Hart, Larry B. Crowder

Secretion of anti-Müllerian hormone in the Florida manatee Trichechus manatus latirostris, with implications for assessing conservation status Secretion of anti-Müllerian hormone in the Florida manatee Trichechus manatus latirostris, with implications for assessing conservation status

Environmental and anthropogenic stressors can affect wildlife populations in a number of ways. For marine mammals (e.g. the Florida manatee Trichechus manatus latirostris), certain stressors or conservation risk factors have been identified, but sublethal effects have been very difficult to assess using traditional methods. The development of 'biomarkers' allows us to correlate effects...
Authors
Rhian C. Wilson, John E. Reynolds, Dana L. Wetzel, Leslie Schwierzke-Wade, Robert K. Bonde, Kevin F. Breuel, William E. Roudebush
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