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Filter Total Items: 3551

Family Cepolidae Family Cepolidae

No abstract available.
Authors
William F. Smith-Vaniz

The factors controlling species density in herbaceous plant communities: An assessment The factors controlling species density in herbaceous plant communities: An assessment

This paper evaluates both the ideas and empirical evidence pertaining to the control of species density in herbaceous plant communities. While most theoretical discussions of species density have emphasized the importance of habitat productivity and disturbance regimes, many other factors (e.g. species pools, plant litter accumulation, plant morphology) have been proposed to be important...
Authors
J.B. Grace

Management implications of fish trap effectiveness in adjacent coral reef and gorgonian habitats Management implications of fish trap effectiveness in adjacent coral reef and gorgonian habitats

A combination of visual census and trap sampling in St. John, USVI indicated that traps performed better in gorgonian habitat than in adjacent coral reef habitat. Although most families were seen more commonly in coral habitat, they were caught more often in gorgonian areas. Traps probably fished more effectively in gorgonian habitats, especially for migrating species, because traps...
Authors
Nicholas Wolff, Rikki Grober-Dunsmore, Caroline S. Rogers, James P. Beets

Root and shoot responses of Taxodium distichum seedlings subjected to saline flooding Root and shoot responses of Taxodium distichum seedlings subjected to saline flooding

Variation among progeny of five half-sib family collections of baldcypress (Taxodium distichum) from three freshwater and two brackish-water seed sources subjected to saline flooding was evaluated Mini-rhizotrons (slant tubes) were used to monitor root elongation for a period of 99 days. Salinity level produced significant effects across all baldcypress half-sib families, with root...
Authors
K. W. Krauss, J. L. Chambers, J. A. Allen, B.P. Luse, A.S. DeBosier

Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.) Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.)

Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus, was investigated by heat shock, cold shock, hydrostatic pressure, and/or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C...
Authors
A.-R.A. El Gamal, K. B. Davis, J.A. Jenkins, Torrans E. Les

Manatee response to boating activity in a thermal refuge Manatee response to boating activity in a thermal refuge

Thermal refuges are important for the endangered Florida manatee (Trichechus manatus latirostris) during winter cold periods in temperate latitudes. However, little research has examined impacts on manatees from human disturbance during these critical periods. We studied the effect of recreational boating activity on manatee use of established sanctuaries in the natural thermal refuge...
Authors
C.A. Buckingham, L.W. Lefebvre, J.M. Schaefer, H. I. Kochman

Effects of spatial grouping on the functional response of predators Effects of spatial grouping on the functional response of predators

A unified mechanistic approach is given for the derivation of various forms of functional response in predator-prey models. The derivation is based on the principle-of-mass action but with the crucial refinement that the nature of the spatial distribution of predators and/or opportunities for predation are taken into account in an implicit way. If the predators are assumed to have a...
Authors
C. Cosner, D.L. DeAngelis, J.S. Ault, D.B. Olson

Relationships between hydraulic parameters in a small stream under varying flow and seasonal conditions Relationships between hydraulic parameters in a small stream under varying flow and seasonal conditions

Twenty conservative tracer injections were carried out in the same reach of a small woodland stream in order to determine how variation in discharge and leaf accumulation affect stream hydraulic parameters. The injections were made at various discharge rates ranging from 2-6 to 40 1/s. Five of the injections were made during late autumn, when there were large accumulations of leaves in...
Authors
D.R. Hart, P. J. Mulholland, E.R. Marzolf, D.L. DeAngelis, S.P. Hendricks

Protocol and practice in the adaptive management of waterfowl harvests Protocol and practice in the adaptive management of waterfowl harvests

Waterfowl harvest management in North America, for all its success, historically has had several shortcomings, including a lack of well-defined objectives, a failure to account for uncertain management outcomes, and inefficient use of harvest regulations to understand the effects of management. To address these and other concerns, the U.S. Fish and Wildlife Service began implementation...
Authors
F. Johnson, K. Williams

[Book review] Wetland restoration: flood pulsing and disturbance dynamics, by Beth Middleton [Book review] Wetland restoration: flood pulsing and disturbance dynamics, by Beth Middleton

Review of: Wetland restoration: Flood pulsing and disturbance dynamics / Beth Middleton / John Wiley & Sons, Inc., 6705 Third Avenue, New York, NY 10158. 1999. 388 pages. ISBN 0-471-29263-X.
Authors
R.G. Boustany

Giant panda (Ailuropoda melanoleuca) population dynamics and bamboo (subfamily Bambusoideae) life history: a structured population approach to examining carrying capacity when the prey are semelparous Giant panda (Ailuropoda melanoleuca) population dynamics and bamboo (subfamily Bambusoideae) life history: a structured population approach to examining carrying capacity when the prey are semelparous

The giant panda, Ailuropoda melanoleuca, is a highly specialized Ursid whose diet consists almost entirely of various species of bamboo. Bamboo (Bambusoideae) is a grass subfamily whose species often exhibit a synchronous semelparity. Synchronous semelparity can create local drops in carrying capacity for the panda. We modeled the interaction of pandas and their bamboo food resources...
Authors
J. Carter, A. S. Ackleh, B.P. Leonard, Hongfang Wang

Cumulative index to chemicals and to common and scientific names of species listed in Contaminant Hazard Reviews 1 through 34 Cumulative index to chemicals and to common and scientific names of species listed in Contaminant Hazard Reviews 1 through 34

The Contaminant Hazard Review (CHR) series--sponsored by the U.S. Geological Survey, Patuxent Wildlife Research Center--synthesizes ecotoxicological data for selected environmental contaminants, with emphasis on hazards to native species of flora and fauna. From 1985 through 1998, 34 reviews were published in various report series of the U.S. Department of the Interior on agricultural...
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