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At least 1,747 records · Page 97Linked to original sources
USGS1976

Ecology of mangroves in the Jewfish Chain, Exuma, Bahamas

The structure and function of mangrove communities in the Jewfish Chain, Exumas, Bahamas, were investigated for 3-1/2 years. Mangrove vegetation in the Jewfish Chain is similar to that in all the Caribbean-Florida area; Rhizophora mangle L. dominates and is interspersed with Avicennia germinans (L.) Lamk. and Laguncularia racemosa (L.) Gaertn. There is no apparent zonation of these three species. The mangrove communities in the Jewfish Chain occur only where they are protected from prevailing winds, storms, and tides, although all are periodically devastated by hurricanes. We found little or no evidence of coast building within these protected locations. The importance of the mangroves appears to be in providing protection and food for other flora and fauna within this unique ecosystem. Twenty-four species of algae were found in the mangroves, 9 of which had not previously been reported from the Bahamas. Distribution of these algae appears to be correlated to incident solar radiation, desiccation, and tide level. A total of 56 species of fish were found in the mangroves, 2 of which were not previously known from the Bahamas. Many fish taken were juveniles, suggesting that mangroves are a nursery ground for numerous species. Nine species of molluscs were found. Each species had a distinct distribution pattern relative to distance from the seaward edge of the mangroves, as well as a distinct vertical distribution pattern. Seventeen species of decapod crustaceans were recorded. Though several species of birds were noted in the mangroves, three species were most abundant: the white-crowned pigeon ( Columba leucocephala ) uses the mangrove for nesting but feeds in nearby shrub-thorn communities; the gray kingbird ( Tyrannus dominicensis ) and green heron ( Butorides virescens ) nest and feed in the mangroves. Our data do not completely describe a stereotyped mangrove community in the Bahamas, but they do give an indication of community structure and suggest several aspects of function.

Conference Paper↗
USGS2007

Sockeye salmon evolution, ecology, and management

This collection of articles and photographs gives managers a good idea of recent research into what the sockeye salmon is and does, covering such topics as the vulnerability and value of sockeye salmon ecotypes, their homing ability, using new technologies to monitor reproduction, DNA and a founder event in the Lake Clark sockeye salmon, marine-derived nutrients, the exploitation of large prey, dynamic lake spawning migrations by females, variability of sockeye salmon residence, expression profiling using cDNA microarray technology, learning from stable isotropic records of native otolith hatcheries, the amount of data needed to manage sockeye salmon and estimating salmon "escapement."

Scitech Book News↗
USGS2000

Would ecological landscape restoration make the Bandelier Wilderness more or less of a wilderness?

The purpose of this paper is to foster discussion on the basic issue of whether it is appropriate or not to intervene in designated wilderness areas that have been “trammeled by man” and, as a result, no longer retain their “primeval character and influence.” We explore this wilderness management dilemma (whether we can or should actively manage wilderness conditions to restore and protect wilderness and other values) by asking seven questions relating to a wilderness area that is no longer “natural.” (For the purposes of this discussion, “natural” is defined by words and phrases used in the 1964 Wilderness Act: “a community of life untrammeled by man”; “land retaining its primeval character and influence”; and or existing in an “unimpaired condition.”) Debate on this issue is not new, but is intensifying, since most wilderness areas in the continental United States are not pristine and ecosystem research has shown that conditions in many are deteriorating. To facilitate dialog on this wilderness management topic we focus on a case-study of a proposed large-scale project to restore piñon-juniper woodlands in the Bandelier Wilderness, New Mexico.

New Mexico↗
USGS1997

Bobcat ( Felis rufus ) ecology and management

The bobcat ( Felis rufus ) is a medium sized predator in the family Felidae found exclusively in North America. Extensive natural history information is available and is summarized in several bibliographies and reviews (Sweeny and Poelker 1977, McCord and Cardoza 1982, Boddicker 1983, Anderson 1987, Rolley 1987). The bobcat is a spotted cat with a short white-tipped tail, small dark ear tufts and is about twice the size of the house cat ( Felis domesticus ) because of the bobcat’s longer bone structure (McCord and Cardoza 1982, Jameson and Peeters 1988). The bobcat weights between 5- 15 kg with males larger than females. TL 700- 1000, T 95-150, E (from crown) 60-75 (Jameson and Peeters 1988).

Conference Paper↗
USGS1997

Gray Fox ( Urocyon cinereoargenteus ) ecology and management

The gray fox ( Urocyon cinereoargenteus ) is a petite member of the family Canidae in the order Carnivora with a long muzzle and pointed ears (Samuel and Nelson 1982). The coat of the gray fox is silver gray across the back with significant amounts of rufus along the sides. This characteristic is often confused by people who see the flash of red and assume that the fox is a red fox ( Vulpes vulpes ). The gray fox has a black tipped tail with a dorsal black stripe that differentiates this species from the kit fox (Vulpes macrotis). The red fox has a white tipped tail. The gray fox weighs between 3-5 kg, occasionally to 7 kg. TL 800-1125, T 275-443, HF 100-150. (Jameson and Peeters 1988).

Conference Paper↗
USGS2014

Defining ecological and economical hydropoweroperations: a framework for managing dam releasesto meet multiple conflicting objectives

Hydroelectric dams are a flexible source of power, provide flood control, and contribute to the economic growth of local communities through real-estate and recreation. Yet the impoundment of rivers can alter and fragment miles of critical riverine habitat needed for other competing needs such as downstream consumptive water use, fish and wildlife population viability, or other forms of recreation. Multiple conflicting interests can compromise progressive management especially with recognized uncertainties related to whether management actions will fulfill the objectives of policy makers, resource managers and/or facility owners. Decision analytic tools were used in a stakeholder-driven process to develop and implement a template for evaluation and prediction of the effects of water resource management of multiple-use systems under the context provided by R.L. Harris Dam on the Tallapoosa River, Alabama, USA. The approach provided a transparent and structured framework for decision-making and incorporated both existing and new data to meet multiple management objectives. Success of the template has been evaluated by the stakeholder governing body in an adaptive resource management framework since 2005 and is ongoing. Consequences of management of discharge at the dam were evaluated annually relative to stakeholder satisfaction to allow for adjustment of both management scenarios and objectives. This template can be applied to attempt to resolve conflict inherent in many dam-regulated systems where management decisions impact diverse values of stakeholders.

Journal of Energy Challenges and Mechanics↗
USGS2000

Notes on status and ecology of the endangered Hawaiian annual Awiwi, Centaurium sebaeoides (Gentianaceae)

The annual, endemic, coastal herb Centaurium sebaeoides is the only native Hawaiian species in the gentian family. The U.S. Fish and Wildlife Service listed it as Endangered under the Endangered Species Act on 29 October 1991. Before surveys reported here, the total population of this species statewide was estimated at 80-110 individuals in eight populations. During counts made in April and May 1997, following ample winter rains, 12 populations of C. sebaeoides with a total of 6300-6600 plants were noted on five islands (Kaua'i, O'ahu, Lana'i, Moloka'i, and Maui). Five populations were mapped with a global positioning system and counted; in the remaining seven populations, the numbers of individuals were estimated. More recent surveys in 1998-1999 estimated a total of only 60-80 individuals at all sites. Such dramatic population fluctuations are believed to be related to the sporadic occurrence of winter rains. Threats that further contribute to the rarity of the species include (1) displacement and overtopping by salt-tolerant nonnative woody species, especially Casuarina spp ., (2) trampling and erosion of habitat by ungulates, and (3) damage caused by off-road vehicles.

Hawaii↗
USGS1997

Status, ecology, and management of the invasive plant, Miconia calvescens DC (Melastomataceae) in the Hawaiian islands

Miconia calvescens (Melastomataceae), native to montane forests of the neotropics, has now invaded wet forests of both the Society and Hawaiian Islands. This tree, which grows up to 15 m tall, is potentially the most invasive and damaging weed of rainforests of Pacific islands. In moist conditions, it grows rapidly, tolerates shade, and produces abundant seed that is effectively dispersed by birds and accumulates in a large, persistent soil seed-bank. Introduced to the Hawaiian Islands in 1961, M. calvescens appears to threaten much of the biological diversity in native forests receiving 1800–2000 mm or more annual precipitation. Currently, M. calvescens is found on 4 Hawaiian islands— Hawaii, Maui, Oahu, and Kauai. Widespread awareness of this invader began in the early 1990s. Although biological control is being pursued, conventional control techniques (mechanical and chemical) to contain and eradicate it locally are underway.

Hawaii↗