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Explore WARC's science publications.

Filter Total Items: 3505

Improving removal-based estimates of abundance by sampling a population of spatially distinct subpopulations Improving removal-based estimates of abundance by sampling a population of spatially distinct subpopulations

A statistical modeling framework is described for estimating the abundances of spatially distinct subpopulations of animals surveyed using removal sampling. To illustrate this framework, hierarchical models are developed using the Poisson and negative-binomial distributions to model variation in abundance among subpopulations and using the beta distribution to model variation in capture
Authors
R.M. Dorazio, H.L. Jelks, F. Jordan

Predicted sex ratio of juvenile Kemp's Ridley sea turtles captured near Steinhatchee, Florida Predicted sex ratio of juvenile Kemp's Ridley sea turtles captured near Steinhatchee, Florida

The Kemp's Ridley (Lepidochelys kempii) is one of the most endangered sea turtles in the world, and it possesses temperature-dependent sex determination (TSD). Sex ratios produced under TSD can vary widely and can affect the reproductive ecology of a population. Therefore, sex ratios produced from TSD are of ecological and conservation interest. The current study validated and utilized a
Authors
A.A. Geis, W.J. Barichivich, T. Wibbels, M. Coyne, A.M. Landry, D. Owens

Southern marl prairies conceptual ecological model Southern marl prairies conceptual ecological model

About 190,000 ha of higher-elevation marl prairies flank either side of Shark River Slough in the southern Everglades. Water levels typically drop below the ground surface each year in this landscape. Consequently, peat soil accretion is inhibited, and substrates consist either of calcitic marl produced by algal periphyton mats or exposed limestone bedrock. The southern marl prairies...
Authors
S.M. Davis, W.F. Loftus, E.E. Gaiser, A.E. Huffman

Water dispersal of vegetative bulbils of the invasive exotic Dioscorea oppositifolia L. in southern Illinois Water dispersal of vegetative bulbils of the invasive exotic Dioscorea oppositifolia L. in southern Illinois

Riparian corridors promote dispersal of several species of exotic invasives worldwide. Dispersal plays a role in the colonization of exotic invasive species into new areas and this study was conducted to determine if the invasiveness of Dioscorea oppositifolia L. (Chinese yam) is facilitated by secondary dispersal of vegetative diaspores (bulbils) by water. Since seed production of this...
Authors
J.R. Thomas, D.J. Gibson, B.A. Middleton

High resolution mapping and classification of oyster habitats in nearshore Louisiana using sidescan sonar High resolution mapping and classification of oyster habitats in nearshore Louisiana using sidescan sonar

Sidescan sonar holds great promise as a tool to quantitatively depict the distribution and extent of benthic habitats in Louisiana's turbid estuaries. In this study, we describe an effective protocol for acoustic sampling in this environment. We also compared three methods of classification in detail: mean-based thresholding, supervised, and unsupervised techniques to classify sidescan...
Authors
Y.C. Allen, C.A. Wilson, H.H. Roberts, J. Supan

Species frequency dynamics in an old-field succession: Effects of disturbance, fertilization and scale Species frequency dynamics in an old-field succession: Effects of disturbance, fertilization and scale

Question: Can patterns of species frequency in an old-field be explained within the context of a metapopulation model? Are the patterns observed related to time, spatial scale, disturbance, and nutrient availability?Location: Upland and lowland old-fields in Illinois, USA.Method: Species richness was recorded annually for seven years following plowing of an upland and lowland old-field...
Authors
David J. Gibson, Beth A. Middleton, K. Foster, Y. A. K. Honu, E. W. Hoyer, M. Mathis

Reproduction and mating behavior of the atlantic flyingfish, Cheilopogon melanurus (Exocoetidae), off North Carolina Reproduction and mating behavior of the atlantic flyingfish, Cheilopogon melanurus (Exocoetidae), off North Carolina

The reproductive biology of Cheilopogon melanurus (Valenciennes, 1847) was examined off North Carolina during the summers of 1991–1992 and 1999–2003. Specimens were collected using a small mesh neuston net and dip nets. A spawning event, the first observation of mating behavior for this species, was recorded off Cape Fear, North Carolina, on 19 August 2003. It was considered to be a...
Authors
Tara L. Casazza, Steve W. Ross, Ann Marie Necaise, Kenneth J. Sulak

Primary production in an impounded baldcypress swamp (Taxodium distichum) at the northern limit of the range Primary production in an impounded baldcypress swamp (Taxodium distichum) at the northern limit of the range

The ability of baldcypress (Taxodium distichum)swamps to maintain themselves near the northern limit of their range depends on their levels of production, which is not only are response to climate but also to local environmental factors(e.g., impoundment). We asked if primary production was reduced under impounded conditions and if species' responses to impoundment were individualistic...
Authors
B.A. Middleton, K.L. McKee

Implications of global climatic change and energy cost and availability for the restoration of the Mississippi delta Implications of global climatic change and energy cost and availability for the restoration of the Mississippi delta

Over the past several thousand years, inputs from the Mississippi River formed the Mississippi delta, an area of about 25,000 km2. Over the past century, however, there has been a high loss of coastal wetlands of about 4800 km2. The main causes of this loss are the near complete isolation of the river from the delta, mostly due to the construction of flood control levees, and pervasive
Authors
John W. Day
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