Skip to main content
U.S. flag

An official website of the United States government

Publications

Explore WARC's science publications.

Filter Total Items: 3510

Genetic structure of natural and restored shoalgrass Halodule wrightii populations in the NW Gulf of Mexico 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...
Authors
S.E. Travis, P. Sheridan

Evaluating the relative contributions of hydroperiod and soil fertility on growth of south Florida mangroves Evaluating the relative contributions of hydroperiod and soil fertility on growth of south Florida mangroves

Low and high water periods create contrasting challenges for trees inhabiting periodically flooded wetlands. Low to moderate flood durations and frequencies may bring nutrient subsidies, while greater hydroperiods can be energetically stressful because of oxygen deficiency. We tested the hypothesis that hydroperiod affects the growth of mangrove seedlings and saplings in a greenhouse...
Authors
K. W. Krauss, T.W. Doyle, R.R. Twilley, V. H. Rivera-Monroy, J.K. Sullivan

Permanent 'phase shifts' or reversible declines in coral cover? Lack of recovery of two coral reefs in St. John, U.S. Virgin Islands Permanent 'phase shifts' or reversible declines in coral cover? Lack of recovery of two coral reefs in St. John, U.S. Virgin Islands

Caribbean coral reefs have changed dramatically in the last 3 to 4 decades, with significant loss of coral cover and increases in algae. Here we present trends in benthic cover from 1989 to 2003 at 2 reefs (Lameshur Reef and Newfound Reef) off St. John, US Virgin Islands (USVI). Coral cover has declined in the fore-reef zones at both sites, and no recovery is evident. At Lameshur Reef...
Authors
C.S. Rogers, J. Miller

Phylogeography, phylogeny and hybridization in trichechid sirenians: Implications for manatee conservation Phylogeography, phylogeny and hybridization in trichechid sirenians: Implications for manatee conservation

The three living species of manatees, West Indian (Trichechus manatus), Amazonian (Trichechus inunguis) and West African (Trichechus senegalensis), are distributed across the shallow tropical and subtropical waters of America and the western coast of Africa. We have sequenced the mitochondrial DNA control region in 330 Trichechus to compare their phylogeographic patterns. In T. manatus...
Authors
J. A. Vianna, Robert K. Bonde, S. Caballero, J. P. Giraldo, R. P. Lima, A. Clark, M. Marmontel, B. Morales-Vela, M. J. De Souza, L. Parr, M. A. Rodriguez-Lopez, A. A. Mignucci-Giannoni, J. A. Powell, F. R. Santos

A structural equation model analysis of postfire plant diversity in California shrublands A structural equation model analysis of postfire plant diversity in California shrublands

This study investigates patterns of plant diversity following wildfires in fire‐prone shrublands of California, seeks to understand those patterns in terms of both local and landscape factors, and considers the implications for fire management. Ninety study sites were established following extensive wildfires in 1993, and 1000‐m2 plots were used to sample a variety of parameters. Data on...
Authors
J.B. Grace, Jon E. Keeley

Influence of propagule flotation longevity and light availability on establishment of introduced mangrove species in Hawai'i Influence of propagule flotation longevity and light availability on establishment of introduced mangrove species in Hawai'i

Although no mangrove species are native to the Hawaiian Archipelago, both Rbizopbora mangle and Bruguiera sexangula were introduced and have become naturalized. Rbizopbora mangle has spread to almost every major Hawaiian island, but B. sexangula has established only on O'ahu, where it was intentionally introduced. To examine the possibility that differences in propagule characteristics...
Authors
J. A. Allen, K. W. Krauss

Assessment of reproductive effects in largemouth bass (Micropterus salmoides) exposed to bleached/unbleached kraft mill effluents Assessment of reproductive effects in largemouth bass (Micropterus salmoides) exposed to bleached/unbleached kraft mill effluents

This study evaluated the potential effects of different concentrations of bleached/unbleached kraft mill effluent (B/UKME) on several reproductive endpoints in adult largemouth bass (Micropterus salmoides). The kraft mill studied produces a 50/50 mix of bleached/unbleached market pulp with an estimated release of 36 million gal of effluent/day. Bleaching sequences were C90d10EopHDp and...
Authors
M. S. Sepulveda, D. S. Ruessler, N. D. Denslow, S. E. Holm, T. R. Schoeb, T. S. Gross

The Amphibian Research and Monitoring Initiative (ARMI): 5-year report The Amphibian Research and Monitoring Initiative (ARMI): 5-year report

The Amphibian Research and Monitoring Initiative (ARMI) is an innovative, multidisciplinary program that began in 2000 in response to a congressional directive for the Department of the Interior to address the issue of amphibian declines in the United States. ARMI’s formulation was cross-disciplinary, integrating U.S. Geological Survey scientists from Biology, Water, and Geography to...
Authors
Erin Muths, Alisa L. Gallant, Evan H. Campbell Grant, William A. Battaglin, David E. Green, Jennifer S. Staiger, Susan C. Walls, Margaret S. Gunzburger, Rick F. Kearney

Response of Tridens flavus (L.) A. S. Hitchc. to soil nutrients and disturbance in an early successional old field Response of Tridens flavus (L.) A. S. Hitchc. to soil nutrients and disturbance in an early successional old field

Soil nutrients and disturbance are two of the main abiotic factors that influence plant dominance (canopy cover), density, and fecundity in early successional old field plant communities. The manner in which the dominant species in old field successional systems respond to the interaction of nutrients and disturbance is poorly known. We examined the dominance, density of flowering...
Authors
Y. A. K. Honu, D.J. Gibson, B.A. Middleton

Water-clover ferns, Marsilea, in the Southeastern United States Water-clover ferns, Marsilea, in the Southeastern United States

A surge in the collection of exotic Marsilea, M. mutica, M. minuta and M. hirsuta in the southeastern United States has prompted the need for updated identification aids. This study provides an annotated key to all water-clover ferns occurring in the region. It describes and illustrates recently documented exotic species and a previously misidentified western introduction. It details the
Authors
Colette C. Jacono, David M. Johnson

The Interface Between Theory and Data in Structural Equation Models 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...
Authors
James B. Grace, Kenneth A. Bollen
Was this page helpful?