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Publications

Explore WARC's science publications.

Filter Total Items: 3374

Bioindicators from Mosquitofish (Gambusia affinis) Sampled from the Imperial Valley in Southern California

The Sonny Bono Salton Sea National Wildlife Refuge (SSNWR) is located 64 km north of the Mexican border at the southern end of the Salton Sea in California's Imperial Valley. Freshwater ponds and managed habitats at the SSNWR, Calipatria, Calif. are supplied with Colorado River water that carries compounds from upstream sources. Components include municipal and industrial discharges, agricultural
Authors
Jill A. Jenkins, Rassa O. Draugelis-Dale

The Interface Between Theory and Data in Structural Equation Models

Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically based probabilistic models. In this paper we discuss the interfa
Authors
James B. Grace, Kenneth A. Bollen

Back to the basics: Lake Tahoe, California /Nevada: Geography and mathematics

Back to the Basics: Lake Tahoe, California/Nevada* continues the Wetland Education Through Maps and Aerial Photography (WETMAAP) Program of exercises on teaching foundational map reading and spatial differentiation skills. It is the third published exercise from the Back to the Basics series developed by the WETMAAP Program. The current exercise modified is from the Lake Tahoe Back to the Basics w
Authors
Lawrence R. Handley, Catherine M. Lockwood, Nathan Handley

Possible effects of the 2004 and 2005 hurricanes on manatee survival rates and movement

Abstract not supplied at this time
Authors
C.A. Langtimm, M. D. Krohn, J. P. Reid, B.M. Stith, C.A. Beck

Relative vulnerability of female turtles to road mortality

Abstract not supplied at this time
Authors
D.A. Steen, M. Aresco, S.G. Beilke, B. Compton, C. K. Dodd, H. Forrester, J.W. Gibbons, J. Greene-McLeod, G. Johnson, T. Langen, M.J. Oldham, D.N. Oxier, R. Sammure, F. Schueler, Jonathan Sleeman, L. L. Smith, J. Tucker, J.P. Gibbs

Possible effects of the 2004 and 2005 hurricanes on manatee survival rates and movement

Abstract not supplied at this time
Authors
C.A. Langtimm, M. D. Krohn, J. P. Reid, B.M. Stith, C.A. Beck

Vanishing before our eyes

No abstract available
Authors
Wylie C. Barrow, William R. Fontenot, Madeline H. Barrow, Richard A. DeMay, David Muth

Evaluation of eelgrass beds mapping using a high-resolution airborne multispectral scanner

Eelgrass (Zostera marina) can provide vital ecological functions in stabilizing sediments, influencing current dynamics, and contributing significant amounts of biomass to numerous food webs in coastal ecosystems. Mapping eelgrass beds is important for coastal water and nearshore estuarine monitoring, management, and planning. This study demonstrated the possible use of high spatial (approximately
Authors
H. Su, D. Karna, E. Fraim, M. Fitzgerald, J. S. Myers, R. Dominguez, B. Coffland, Lawrence R. Handley, T. Mace

A multivariate model of plant species richness in forested systems: Old-growth montane forests with a long history of fire

Recently, efforts to develop multivariate models of plant species richness have been extended to include systems where trees play important roles as overstory elements mediating the influences of environment and disturbance on understory richness. We used structural equation modeling to examine the relationship of understory vascular plant species richness to understory abundance, forest structure
Authors
D.C. Laughlin, J.B. Grace

Assessment of gamete quality for the eastern oyster (Crassostrea virginica) by use of fluorescent dyes

Evaluation of sperm motility is the single most widely used parameter to determine semen quality in mammals and aquatic species. While a good indicator for fresh sperm viability, post-thaw motility is not always effective at predicting fertilizing ability. Techniques using fluorescent dyes can assess functionality of mammalian sperm, but have not been widely applied in aquatic organisms. The easte
Authors
C. G. Paniagua-Chavez, J. Jenkins, M. Segovia, T.R. Tiersch

Responses of neotropical mangrove seedlings grown in monoculture and mixed culture under treatments of hydroperiod and salinity

We investigated the combined effects of salinity and hydroperiod on seedlings of Rhizophora mangle and Laguncularia racemosa grown under experimental conditions of monoculture and mixed culture by using a simulated tidal system. The objective was to test hypotheses relative to species interactions to either tidal or permanent flooding at salinities of 10 or 40 g/l. Four-month-old seedlings were ex
Authors
P. Cardona-Olarte, R.R. Twilley, K. W. Krauss, V. Rivera-Monroy

Genetic structure of natural and restored shoalgrass Halodule wrightii populations in the NW Gulf of Mexico

The decline of seagrass communities worldwide has sparked an urgent need for effective restoration strategies, which require a working knowledge of population genetic structure. Halodule wrighti is a common seagrass of the Caribbean region that is being restored to areas of the Gulf of Mexico, yet little is known of its population genetics. This study provides an assessment of individual, clonal a
Authors
S.E. Travis, P. Sheridan