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Explore WARC's science publications.

Filter Total Items: 3348

Population dynamics and mutualism: Functional responses of benefits and costs

We develop an approach for studying population dynamics resulting from mutualism by employing functional responses based on density‐dependent benefits and costs. These functional responses express how the population growth rate of a mutualist is modified by the density of its partner. We present several possible dependencies of gross benefits and costs, and hence net effects, to a mutualist as fun
Authors
J. Nathaniel Holland, Donald L. DeAngelis, Judith L. Bronstein

Multibeam mapping of the Pinnacles region, Gulf of Mexico

Recent USGS mapping shows an extensive deep (~100 m) reef tract occurs on the Mississippi-Alabama outer continental shelf (Figure 1). The tract, known as "The Pinnacles", is apparently part of a sequence of drowned reef complexes along the "40-fathom" shelf edge of the northern Gulf of Mexico (Ludwick and Walton, 1957). It is critical to determine the accurate geomorphology of these deep-reefs bec
Authors
James V. Gardner, Peter Dartnell, Kenneth J. Sulak

Structural instability, multiple stable states, and hysteresis in periphyton driven by phosphorus enrichment in the Everglades

Periphyton is a key component of the Everglades ecosystems. It is a major primary producer, providing food and habitat for a variety of organisms, contributing material to the surface soil, and regulating water chemistry. Periphyton is sensitive to the phosphorus (P) supply and P enrichment has caused dramatic changes in the native Everglades periphyton assemblages. Periphyton also affects P avail
Authors
Quan Dong, Paul V. McCormick, Fred H. Sklar, Donald L. DeAngelis

Seasonal reproductive cycles for Florida largemouth bass

No abstract available.
Authors
Timothy S. Gross, Maria S. Sepulveda, Carla M. Wieser, Jon J. Wiebe, Trenton R. Schoeb, Nancy D. Denslow, William E. Johnson

How often do fishes "run on empty"?

We used a large data set of African, Neotropical, and North American fishes to examine the frequency with which fishes have empty stomachs (nspecies = 254; nindividuals = 36 875). Mean percentage of empty stomachs was low across all fishes (16.2 ± 1.2%) but varied from 0% to 79.4% among individual species. Nocturnal fishes had empty stomachs more frequently than diurnal fishes. Trophic classificat
Authors
D.A. Arrington, K.O. Winemiller, W.F. Loftus, S. Akin

Mangrove isotopic (δ15N and δ13C) fractionation across a nitrogen vs. phosphorus limitation gradient

Mangrove islands in Belize are characterized by a unique switching from nitrogen (N) to phosphorus (P) limitation to tree growth from shoreline to interior. Fertilization has previously shown that Rhizophora mangle (red mangrove) fringe trees (5–6 m tall) growing along the shoreline are N limited; dwarf trees (≤ 1.5 m tall) in the forest interior are P limited; and transition trees (2–4 m tall) ar
Authors
Karen L. McKee, Ilka C. Feller, Marianne Popp, Wolfgang Wanek

Genetic diversity in a morphologically conservative invasive taxon: Multiple introductions of swamp eels to the southeastern United States

Genetic analysis of introduced populations, especially in morphologically conservative taxa, can clarify introduction histories, identify management units and source populations, provide a more realistic estimate of the frequency of successful invasion, and suggest strategies for preventing further introductions. In the last 7 years, populations of swamp eels, referred to the Asian genus Monopteru
Authors
T.M. Collins, J.C. Trexler, L.G. Nico, T.A. Rawlings

Optimal exploitation of spatially distributed trophic resources and population stability

The relationships between optimal foraging of individuals and population stability are addressed by testing, with a spatially explicit model, the effect of patch departure behaviour on individual energetics and population stability. A factorial experimental design was used to analyse the relevance of the behavioural factor in relation to three factors that are known to affect individual energetics
Authors
A. Basset, M. Fedele, D.L. DeAngelis

Effects of canopy gaps and flooding on homopterans in a bottomland hardwood forest

Canopy disturbance is a major factor affecting forest structure and composition and, as a result of habitat alterations, can influence insect communities. We initiated a field study to quantify the effects of canopy disturbance on aerial insect abundance and distribution within a bottomland hardwood forest along the Cache River, Arkansas, USA. We used passive flight-intercept traps to sample insec
Authors
L.E. Gorham, S.L. King, B. D. Keeland, S. Mopper

Effects of a coastal golf complex on water quality, periphyton, and seagrass

The objective of this study was to provide baseline information on the effects of a golf course complex on water quality, colonized periphyton, and seagrass meadows in adjacent freshwater, near-coastal, and wetland areas. The chemical and biological impacts of the recreational facility, which uses reclaimed municipal wastewater for irrigation, were limited usually to near-field areas and decreased
Authors
M.A. Lewis, R.G. Boustany, D.D. Dantin, R.L. Quarles, J.C. Moore, R. S. Stanley

Generalized avian dispersal syndrome contributes to Chinese tallow tree (Sapium sebiferum, Euphorbiaceae) invasiveness

Plants possessing generalized dispersal syndromes are likely to be more invasive than those relying on specialist dispersal agents. To address this issue on a local and regional scale, avian seed dispersal of the invasive alien Chinese tallow tree (Sapium sebiferum (L.) Roxb.) was assessed in forests and spoil areas of South Carolina and along forest edges in Louisiana during the 1997-99 fruiting
Authors
I.J. Renne, W.C. Barrow, Lori A. Randall Johnson, W.C. Bridges