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Filter Total Items: 3551

Transitions of interaction outcomes in a uni-directional consumer-resource system Transitions of interaction outcomes in a uni-directional consumer-resource system

A uni-directional consumer–resource system of two species is analyzed. Our aim is to understand the mechanisms that determine how the interaction outcomes depend on the context of the interaction; that is, on the model parameters. The dynamic behavior of the model is described and, in particular, it is demonstrated that no periodic orbits exist. Then the parameter (factor) space is shown...
Authors
Y. Wang, Donald L. DeAngelis

Estimating trends in alligator populations from nightlight survey data Estimating trends in alligator populations from nightlight survey data

Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of...
Authors
Ikuko Fujisaki, F.J. Mazzotti, R.M. Dorazio, Kenneth G. Rice, M. Cherkiss, B. Jeffery

Fish as major carbonate mud producers and missing components of the tropical carbonate factory Fish as major carbonate mud producers and missing components of the tropical carbonate factory

Carbonate mud is a major constituent of recent marine carbonate sediments and of ancient limestones, which contain unique records of changes in ocean chemistry and climate shifts in the geological past. However, the origin of carbonate mud is controversial and often problematic to resolve. Here we show that tropical marine fish produce and excrete various forms of precipitated...
Authors
C.T. Perry, M.A. Salter, A.R. Harborne, S.F. Crowley, Howard L. Jelks, R.W. Wilson

Effect of cryopreservation and in vitro culture of bovine fibroblasts on histone acetylation levels and in vitro development of hand-made cloned embryos Effect of cryopreservation and in vitro culture of bovine fibroblasts on histone acetylation levels and in vitro development of hand-made cloned embryos

In this study, the relative acetylation levels of histone 3 in lysine 9 (H3K9ac) in cultured and cryopreserved bovine fibroblasts was measured and we determined the influence of the epigenetic status of three cultured (C1, C2 and C3) donor cell lines on the in vitro development of reconstructed bovine embryos. Results showed that cryopreservation did not alter the overall acetylation...
Authors
L. Chacon, M.C. Gomez, J.A. Jenkins, S.P. Leibo, G. Wirtu, B.L. Dresser, C.E. Pope

Geographic profiling to assess the risk of rare plant poaching in natural areas Geographic profiling to assess the risk of rare plant poaching in natural areas

We demonstrate the use of an expert-assisted spatial model to examine geographic factors influencing the poaching risk of a rare plant (American ginseng, Panax quinquefolius L.) in Shenandoah National Park, Virginia, USA. Following principles of the analytic hierarchy process (AHP), we identified a hierarchy of 11 geographic factors deemed important to poaching risk and requested law...
Authors
J.A. Young, F.T. Van Manen, C.A. Thatcher

A field test of attractant traps for invasive Burmese pythons (Python molurus bivittatus) in southern Florida A field test of attractant traps for invasive Burmese pythons (Python molurus bivittatus) in southern Florida

Context. Invasive Burmese pythons (Python molurus bivittatus) are established over thousands of square kilometres of southern Florida, USA, and consume a wide range of native vertebrates. Few tools are available to control the python population, and none of the available tools have been validated in the field to assess capture success as a proportion of pythons available to be captured...
Authors
R.N. Reed, K.M. Hart, G.H. Rodda, F.J. Mazzotti, R.W. Snow, M. Cherkiss, R. Rozar, S. Goetz

Search behavior of arboreal insectivorous migrants at gulf coast stopover sites in spring Search behavior of arboreal insectivorous migrants at gulf coast stopover sites in spring

Search behavior of arboreal insectivorous migrants was studied at three stopover sites along the northern coast of the Gulf of Mexico during spring migrations, 1993–1995. We examined if search behavior was affected by phylogeny, or by environmental factors. A sequence of search movements (hop, flutter, or flight) in a foraging bout was recorded for each migrant encountered. Search rate...
Authors
Chao-Chieh Chen, W.C. Barrow, K. Ouchley, R.B. Hamilton

A predator-prey model with a holling type I functional response including a predator mutual interference A predator-prey model with a holling type I functional response including a predator mutual interference

The most widely used functional response in describing predator-prey relationships is the Holling type II functional response, where per capita predation is a smooth, increasing, and saturating function of prey density. Beddington and DeAngelis modified the Holling type II response to include interference of predators that increases with predator density. Here we introduce a predator...
Authors
G. Seo, D.L. DeAngelis

Estimating trends in alligator populations from nightlight survey data Estimating trends in alligator populations from nightlight survey data

Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of...
Authors
Ikuko Fujisaki, Frank J. Mazzotti, Robert M. Dorazio, Kenneth G. Rice, Michael Cherkiss, Brian Jeffery

Tampa Bay Tampa Bay

Tampa Bay is Florida’s largest open-water estuary and encompasses an area of approximately 1036 km2 (400 mi2) (Burgan and Engle, 2006; TBNEP, 2006). The Bay’s watershed drains 5,698 km2 (2,200 mi2) of land and includes freshwater from the Hillsborough River to the north east, the Alafia and Little Manatee rivers to the east, and the Manatee River to the south (Figure 1). Freshwater...
Authors
Lawrence R. Handley, Kathryn Spear, Lindsay Cross, René Baumstark, Ryan Moyer, Cindy A. Thatcher

Abnormal alligators and organochlorine pesticides in Lake Apopka, Florida Abnormal alligators and organochlorine pesticides in Lake Apopka, Florida

No abstract available.
Authors
Allan R. Woodward, H. Franklin Percival, R. Heath Rauschenberger, Timothy S. Gross, Kenneth G. Rice, Roxanne Conrow
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