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Explore WARC's science publications.

Filter Total Items: 3374

Species richness and patterns of invasion in plants, birds, and fishes in the United States

We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following declines in potential evapotranspiration, mean temperature,
Authors
Thomas J. Stohlgren, David Barnett, Curtis Flather, Pamela L. Fuller, Bruce G. Peterjohn, John Kartesz, Lawrence L. Master

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 rediscove
Authors
Colette C. Jacono, David M. Johnson

Cooperative Manatee Research in Puerto Rico

Abstract not supplied at this time
Authors
James P. Reid

Keystone predators (eastern newts, Notophthalmus viridescens) reduce the impacts of an aquatic invasive species

Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence
Authors
Kevin G. Smith

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 CEHD for so
Authors
M. S. Sepulveda, D. S. Ruessler, N. D. Denslow, S. E. Holm, T. R. Schoeb, T. S. Gross

Electrocardiography in two subspecies of manatee (Trichechus manatus latirostris and Trichechus manatus manatus)

Electrocardiographic (ECG) measurements were recorded in two subspecies of awake, apparently healthy, wild manatees (Trichechus manatus latirostris and T. m. manatus) undergoing routine field examinations in Florida and Belize. Six unsedated juveniles (dependent and independent calves) and 6 adults were restrained in ventral recumbency for ECG measurements. Six lead ECGs were recorded for all mana
Authors
J. Siegal-Willott, A. Estrada, R. K. Bonde, A. Wong, D.J. Estrada, K. Harr

G-banded karotype and ideogram for the critically endangered North Atlantic right whale (Eubalanea glacialis)

Published cytogenetic data for extant cetacean species remain incomplete. In a review of the literature, we found karyotypic information for 6 of the 13 tentatively recognized species of the suborder Mysticeti (baleen whales). Among those yet to be described is the critically endangered North Atlantic right whale (Eubalaena glacialis). Herein, we describe and propose a first-generation G-banded ka
Authors
K.C. Pause, R. K. Bonde, P.M. McGuire, Roberto T. Zori, B.A. Gray

Daily energy expenditure in free-ranging Gopher Tortoises (Gopherus polyphemus)

Studies of ecological energetics in chelonians are rare. Here, we report the first measurements of daily energy expenditure (DEE) and water influx rates (WIRs) in free-ranging adult Gopher Tortoises (Gopherus polyphemus). We used the doubly labeled water (DLW) method to measure DEE in six adult tortoises during the non-breeding season in south-central Mississippi, USA. Tortoise DEE ranged from 76.
Authors
P.G.R. Jodice, D.M. Epperson, G. Henk Visser

Invasion in a diversity hotspot: Exotic cover and native richness in the Californian serpentine flora

Exotic species have been observed to be more prevalent in sites where the richness of native species is highest, possibly reflecting variation among sites in resources, propagule supply, heterogeneity, or disturbance. However, such a pattern leaves unclear whether natives at species-rich sites are subject to especially severe impacts from exotics as a result. We considered this question using path
Authors
S. Harrison, J.B. Grace, K.F. Davies, H.D. Safford, J.H. Viers

Biofouling and the continuous monitoring of underwater light from a seagrass perspective

For more than a decade, inexpensive electronic instruments have made continuous underwater light monitoring an integral part of many seagrass studies. Although biofouling, if not controlled, compromises the utility of the record. A year-long assessment of the time course of sensor fouling, in the Laguna Madre of Texas established that light transmitted through the fouling layer after 2 wk of expos
Authors
C.P. Onuf

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 community
Authors
J.B. Grace, J. E. Keeley

Interpreting the spatio-temporal patterns of sea turtle strandings: Going with the flow

Knowledge of the spatial and temporal distribution of specific mortality sources is crucial for management of species that are vulnerable to human interactions. Beachcast carcasses represent an unknown fraction of at-sea mortalities. While a variety of physical (e.g., water temperature) and biological (e.g., decomposition) factors as well as the distribution of animals and their mortality sources
Authors
K.M. Hart, P. Mooreside, L.B. Crowder