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Explore WARC's science publications.

Filter Total Items: 3346

Prey vulnerability to peacock cichlids and largemouth bass based on predator gape and prey body depth

The interaction of prey fish body depth and predator gape size may produce prey assemblages dominated by invulnerable prey and excessive prey-to-predator biomass ratios. Peacock cichlids (Cichla ocellaris) were stocked into southeast Florida canals to consume excess prey fish biomass, particularly spotted tilapia (Tilapia mariae). The ecomorphologically similar largemouth bass (Micropterus salmoid
Authors
Jeffrey E. Hill, Leo G. Nico, Charles E. Cichra, Carter R. Gilbert

Landscape characteristics of Rhizophora mangle forests and propagule deposition in coastal environments of Florida (USA)

Field dispersal studies are seldom conducted at regional scales even though reliable information on mid-range dispersal distance is essential for models of colonization. The purpose of this study was to examine the potential distance of dispersal of Rhizophora mangle propagules by comparing deposition density with landscape characteristics of mangrove forests. Propagule density was estimated at va
Authors
R. Sengupta, B. Middleton, C. Yan, M. Zuro, H. Hartman

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 subject to cro
Authors
David J. Gibson, Beth A. Middleton, K. Foster, Y. A. K. Honu, E. W. Hoyer, M. Mathis

Relationships between gap makers and gap fillers in an Arkansas floodplain forest

Question:In floodplain forests, does frequent flooding allow for self-replacement of shade-intolerant tree species or do small canopy gap openings lead to replacement by shade-tolerant tree species?Location:Cache River, Arkansas, US; 55 m a.s.l.Methods:The species, diameter-at-breast height, and elevation of primary gap-maker trees were determined for new gaps from 1995–1998. The size and species
Authors
Sammy L. King, T. J. Antrobus

Genetic effects of a large-scale Spartina alterniflora (smooth cordgrass) dieback and recovery in the northern Gulf of Mexico

A large-scale dieback event struck marshes along the northwestern Gulf of Mexico coast during summer 2000, in apparent response to a prolonged and severe drought. Along the Louisiana coast, large areas of the dominant marsh species, Spartina alterniflora, turned brown, followed by death of at least the aboveground structures of entire plant mortality. Key ecological and genetic measures were studi
Authors
K.R. Edwards, S.E. Travis, C.E. Proffitt

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 testoster
Authors
A.A. Geis, W.J. Barichivich, T. Wibbels, M. Coyne, A.M. Landry, D. Owens

Woody debris in the mangrove forests of South Florida

Woody debris is abundant in hurricane‐impacted forests. With a major hurricane affecting South Florida mangroves approximately every 20 yr, carbon storage and nutrient retention may be influenced greatly by woody debris dynamics. In addition, woody debris can influence seedling regeneration in mangrove swamps by trapping propagules and enhancing seedling growth potential. Here, we report on line‐i
Authors
K. W. Krauss, T.W. Doyle, R.R. Twilley, T. J. Smith, K.R.T. Whelan, J.K. Sullivan

Life history trade-offs and community dynamics of small fishes in a seasonally pulsed wetland

We used a one-dimensional, spatially explicit model to simulate the community of small fishes in the freshwater wetlands of southern Florida, USA. The seasonality of rainfall in these wetlands causes annual fluctuations in the amount of flooded area. We modeled fish populations that differed from each other only in efficiency of resource utilization and dispersal ability. The simulations showed th
Authors
D.L. DeAngelis, J.C. Trexler, W.F. Loftus

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 or more gen
Authors
B.A. Middleton, K.L. McKee

Back to the basics: Birmingham, Alabama, measurement and scale

Back to the Basics: Birmingham, Alabama is the fourth in a series of workshops that focus on teaching foundational map reading and spatial differentiation skills. It is the second published exercise from the Back to the Basics series developed by the Wetland Education through Maps and Aerial Photography (WETMAAP) Program (see Journal of Geography 103, 5: 226-230). Like its predecessor, the current
Authors
Lawrence R. Handley, Catherine M. Lockwood, Nathan Handley

Spartina alterniflora genotype influences facilitation and suppression of high marsh species colonizing an early successional salt marsh

Genetically based phenotypic and ecotypic variation in a dominant plant species can influence ecological functions and patterns of recruitment by other species in plant communities. However, the nature and degree of importance of genotypic differences is poorly understood in most systems.The dominant salt marsh species, Spartina alterniflora, is known to induce facilitative and competitive effects
Authors
C.E. Proffitt, R.L. Chiasson, A.B. Owens, K.R. Edwards, S.E. Travis

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 plant has
Authors
J.R. Thomas, D.J. Gibson, B.A. Middleton