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Landscape-Scale Population Dynamics: Field Observations And Modelling Of Puya Hamata, A Flagship Plant From The Andes, Paola M. García-Meneses

Other Faculty of Science and Engineering Theses

Important ecological processes happen over long periods of time and at the landscape scale. Effective conservation of biodiversity and management of natural resources and ecosystem services requires an understanding of these processes. Unfortunately, it is often impractical to conduct appropriate long-term, landscape-scale studies. Modelling offers an alternative approach. Complete ecosystems are too complex to model practically, but simulations of simplified systems provide useful insights of practical value. LandBaSE-P is an individual-based model for Puya hamata that provides information about impacts of fire on ecological processes in the páramo of the Reserva Ecológica El Ángel, Ecuador. Puya hamata is a flagship …

Management In A Neotropical Show Cave: Planning For Invertebrates Conservation, Thais Giovannini Pellegrini, Rodrigo Lopes Ferreira

International Journal of Speleology

Lapa Nova is a dolomitic cave about 4.5 km long located in northwestern Minas Gerais state, Brazil. The cave experiences intense tourism, concentrated over a single period of the year, during the Feast of Our Lady of Lapa. In order to evaluate the impacts felt by the invertebrate community from this tourism, a new methodology was proposed. Four types of areas (intense visitation area, outlying visitation areas, moderate visitation areas and no-visitation areas) were sampled for invertebrates. There was one sampling prior and another on the last day of the 128^th feast, to evaluate the effects of visitation on …

Distributed Graduate Seminars: An Interdisciplinary Approach To Studying Land Conservation, Jessica Owley, Adena R. Rissman

Articles

No abstract provided.

Carrying Capacity For Species Richness As A Context For Conservation: A Case Study Of North American Breeding Birds, Andrew J. Hansen, Linda Bowers Phillips, Curtis H. Flather, Jim Robinson-Cox

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Aim To demonstrate that the concept of carrying capacity for species richness (S_K) is highly relevant to the conservation of biodiversity, and to estimate the spatial pattern of S_K for native landbirds as a basis for conservation planning.

Location North America.

Methods We evaluated the leading hypotheses on biophysical factors affecting species richness for Breeding Bird Survey routes from areas with little influence of human activities.We then derived a best model based on information theory, and used this model to extrapolate SK across North America based on the biophysical predictor variables. The predictor variables included the …

Number 52 (December 2010), Southern Fishes Council

Southeastern Fishes Council Proceedings

(December 2010) - Comparative Conservation Genetics of Two Endangered Darters, Percina rex and Percina jenkinsi By Anna L. George, David Neely, and Richard Mayden

Invasion of Gulf Menhaden in the Alabama River By T. Heath Haley, R. Kyle Bolton, and Carol E. Johnston

Southeastern Fishes Council State Reports

Minutes, Business Meeting, 35th Annual Meeting, Southeastern Fishes Council

2009 Treasurer's Report for the Southeastern Fishes Council

Habitat Models As A Research Gap In Biodiversity Conservation In Tropical Rain Forest Of Southeast Asia, Mona Nazeri, Jusoff Kamaruzzaman, Nima Madani

International Congress on Environmental Modelling and Software

Tropical rain forests, the richest terrestrial ecosystem on earth are disappearing due to land use changes mainly agricultural activities and timber logging. Habitat alteration and as a result fragmentation have direct effect on species survival trough lose of connectivity between suitable habitats. Without a doubt the traditional strategies for protecting different wildlife species in this region was not successful enough to guarantee the survival of remaining biodiversity. Distribution modelling which, very little has been studied in the region, is significantly important for biodiversity conservation programs. Distribution data can determine all the areas that can have high potential of occupancy by …

Habitat Models As A Research Gap In Biodiversity Conservation In Tropical Rain Forest Of Southeast Asia, Mona Nazeri, Jusoff Kamaruzzaman, Nima Madani

International Congress on Environmental Modelling and Software

Tropical rain forests, the richest terrestrial ecosystem on earth are disappearing due to land use changes mainly agricultural activities and timber logging. Habitat alteration and as a result fragmentation have direct effect on species survival trough lose of connectivity between suitable habitats. Without a doubt the traditional strategies for protecting different wildlife species in this region was not successful enough to guarantee the survival of remaining biodiversity. Distribution modelling which, very little has been studied in the region, is significantly important for biodiversity conservation programs. Distribution data can determine all the areas that can have high potential of occupancy by …

Effects Of Light And Temperature On Germination Of Pyxidanthera Brevifolia Wells (Diapensiaceae), Wade A. Wall, Jacob L. Hilton, Thomas R. Wentworth, Janet B. Gray, Matthew G. Hohmann, William A. Hoffmann

United States Army Corps of Engineers, Omaha District

Pyxidanthera brevifolia is an evergreen semiwoody cushion plant endemic to the Sandhills of North and South Carolina, with the majority of populations occurring on Fort Bragg Military Reservation in North Carolina. Currently the species is listed as Endangered in North Carolina and is designated as a Species at Risk (SAR) by the US Department of Defense. Previous studies have suggested that seeds may not be viable because they failed to germinate under controlled conditions. Our objectives in this study were to attempt germination of Pyxidanthera brevifolia seeds, determine the best temperature conditions for germination, and understand more about germination requirements …

Toward A Strategy For The Conservation And Protection Of The World’S Temperate Grasslands, William D. Henwood

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Temperate grasslands are one of the world’s great biomes and were once home to some of the largest assemblages of wildlife the earth has ever known. Today these grasslands are considered the most altered terrestrial ecosystem on the planet and are recognized as the most endangered ecosystem on most continents. While species and habitat declines continue, temperate grasslands have the lowest level of protection of the world’s 14 biomes. With only 4% of the biome under protected status, considerable effort will be required to increase this level of protection. Several international bodies have suggested that achieving at least a 10% …

Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug

Theses and Dissertations

The dark kangaroo mouse, Microdipodops megacephalus, is a sensitive species in the Great Basin Desert. This thesis explores the structure of desert rodent communities of the Great Basin to better understand M. megacephalus' place in the community and the conditions that promote large and stable populations. To determine community structure, I used nestedness analysis to evaluate 99 communities of nocturnal granivorous rodents. I found that the community structure was non-random, indicating the existence of assembly rules and ecological constraints. I also found that M. megacephalus was the second most vulnerable species in the community. To explore the correlation …

Conserving Migratory Land Birds In The New World: Do We Know Enough?, John Faaborg, Richard T. Holmes, Angela D. Anders, Keith L. Bildstein

Dartmouth Scholarship

Migratory bird needs must be met during four phases of the year: breeding season, fall migration, wintering, and spring migration; thus, management may be needed during all four phases. The bulk of research and management has focused on the breeding season, although several issues remain unsettled, including the spatial extent of habitat influences on fitness and the importance of habitat on the breeding grounds used after breeding. Although detailed investigations have shed light on the ecology and population dynamics of a few avian species, knowledge is sketchy for most species. Replication of comprehensive studies is needed for multiple species across …

Applying Palaeoecology To Conservation: A Long-Term Perspective For Informed Management Of A Fynbos Nature Reserve, James Macpherson

The Plymouth Student Scientist

This investigation proposes that long-term perspectives are essential in ecological conservation/restoration. Such a perspective is particularly important for fynbos, which has been substantially altered by an unspecified level of anthropogenic disturbance. Fossil pollen and micro-charcoal deposits are used to establish a proxy record for ecosystem state that can be applied to conservation. This is carried out at a nature reserve in the Langeberg Range, Western Cape, South Africa. Modern pollen-vegetation relationships are also examined to reduce inaccuracies in the fossil record. Three distinct phases are identified for the reserve over a period extending up to ~1000 years before present (BP). …

Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz

EEB Articles

Populations of anadromous alewives (Alosa pseudoharengus) are declining throughout much of their range, particularly in southern New England where fishery moratoriums have recently been instituted in three states. The alewife run at Bride Brook, a coastal stream in East Lyme, Connecticut, was studied from 2003-06 to assess shifts in demography and life history. Annual censuses of abundance, along with sampling for size, age, and spawning history structure were conducted. These data were compared to similar data in 1966-67 at this site. Recent alewife runs at Bride Brook featured lower abundance and younger, smaller fish that were less likely to be …

Balancing The Conservation Of Wildlife Habitat With Road Access For Subsistence Hunting In Yakutat, Alaska, Colin S. Shanley

Biological Sciences

"This thesis was an interdisciplinary investigation with the goal of balancing the conservation of wildlife habitat with road access for subsistence hunting in Yakutat, Alaska. The problem posed by land managers and subsistence moose hunters revolved around the use of off-highway vehicles (OHVs; e.g. 'four-wheelers') for subsistence moose hunting and the potential disturbance OHVs have on moose. This complex social-ecological problem is becoming an increasingly common management dilemma faced by rural mixed cash-subsistence communities across the Circumpolar North. I addressed this problem in two chapters with a combination of methods from wildlife ecology, landscape modeling, subsistence land-use, and scenario planning. …

Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher E. Bernhardt, Randall J. Mitchell, Helen J. Michaels

Biology Faculty Research

Both the number and the density of flowering plants in a population can be important determinants of pollinator abundance and behavior. We report the joint effects of population size and density on pollinator visitation and pollination success for Lupinus perennis (Fabaceae). Focusing on five pairs of populations, we matched one small population (125-800 flowering plants) with one distinctly larger population (1000-3000 flowering plants). In these pairs, population size did not affect pollinator communities or pollination success. All measures of pollination success increased significantly with density. Only bee behavior (number of flowers probed per inflorescence) exhibited a significant interaction of size …

Management Of The Houtman Abrolhos System. A Draft Review 2007 - 2017, Department Of Fisheries (Western Australia) On Advice From The Abrolhos Islands Management Advisory Committee

Fisheries Management Papers

This review contains a brief description of the Abrolhos System and its special values. It also states the goal and principal objectives for management during the next ten years (2006-2016), along with updated strategies to achieve these objectives. The document succinctly outlines the direction for multiple use management of the Houtman Abrolhos Islands as determined by the Abrolhos Islands Management Advisory Committee (AIMAC). The Committee’s role is to advise the Minister for Fisheries on management of the Abrolhos Islands and the Abrolhos Islands Fish Habitat Protection Area.

Heylen Bvba (Belgium), Thomas Cooney

Case studies

As Tom Heylen reflects upon his early days in business, he often wonders how his company Heylen bvba survived. He had left university after just one year of studying biology in order to pursue a business opportunity that he believed existed in the market and that needed to be acted upon without delay. About that time, nature had become modified to such an extent (particularly in Europe) that biodiversity could only be conserved through active management and restoration of the few natural areas which remained. Such management required innovation, specialised equipment, and knowledge in order to be successful. But those …

Anadromous Rainbow Smelt And Tomcod In Connecticut: Assessment Of Populations, Conservation Status, And Need For Restoration Plan, Heather A. Fried, Eric T. Schultz

EEB Articles

(beginning of rainbow smelt executive summary)

Evidence indicates that anadromous rainbow smelt (Osmerus mordax) populations in Connecticut and elsewhere in the northeast United States have severely declined. Several sampling programs have documented declines in Connecticut’s smelt populations over the last three decades (Marcy 1976a, Marcy 1976b, Millstone Environmental Laboratory 2005). Similar declines have also been documented in the Hudson River (ASA Analysis & Communication 2005) and in Massachusetts (personal communication, Brad Chase, MA Division of Marine Fisheries 2004). Recreational and commercial fisheries in the region for this species have virtually ceased (Blake and Smith 1984). The Connecticut Fish Advisory Committee …

Assessment Of Anadromous Alewife And Blueback Herring Populations In Connecticut Coastal Streams And Connecticut River Tributaries, Justin P. Davis, Eric T. Schultz

EEB Articles

Alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis) occur in anadromous populations that have a largely overlapping distribution from Florida to Newfoundland (Loesch 1987). Anadromous populations of these species are commonly collectively referred to as “river herring”. Adults inhabit coastal shelf waters until sexual maturity is reached at age 3-5 (Neves 1981). Sexually mature individuals make spawning migrations, commonly referred to as “runs”, into freshwater systems during spring months (Loesch 1987). Spawners can survive and return to spawn in subsequent years (Mullen et al. 1986). Juveniles reside in freshwater for 3-7 months, at which time they undertake a gradual migration …

Emerging Policy Issues On Non-Timber Forest Products In Nepal, Ranu Shrestha-Acharya, Joel Heinen

HIMALAYA, the Journal of the Association for Nepal and Himalayan Studies

No abstract provided.

Physical And Chemical Characteristics Of Water In Selected Locations In Lake Victoria, Tanzania, M A Kishe

Tanzania Journal of Science

A study conducted during the period of March/April 2002 aimed at measuring physical and chemical parameters in Tanzanian portion of Lake Victoria. Temperature and conductivity values were homogeneous among and within the study stations. Levels of dissolved oxygen (DO) ranged from 4 - 9 mgl-1 and there was significant difference between stations (P < 0.05). Water transparency was poor (< 2 m secchi depth) and differed from one sampling station to another. Ammonium nitrogen (NH4+-N), with few exceptions, showed the highest concentrations both at the bottom and near-surface followed by total phosphates (TP), nitrate nitrogen (NO2+NO3--N), nitrite nitrogen (NO2--N) and Soluble Reactive Silicon (SRSi). Concentrations of NH4+-N, TP and SRSi were high at bottom waters and the reverse was true for NO2+NO3--N and NO2--N. Differences in nutrients and physical water parameters among sampling stations were statistically significant (P < 0.05). However, temperature and nutrient levels at studied areas were higher than that of 50 years ago and the trend reversed for DO and transparency. This indicates that Lake Victoria is receiving organic materials from the catchment area leading to the decline of water quality. Long-term efforts for rehabilitation, conservation and sustainable management of the lake are suggested.

The Ecology Of Lianas And Their Role In Forests, Stefan A. Schnitzer, Frans Bongers

Biological Sciences Faculty Research and Publications

Recent studies have demonstrated the increasingly important role of lianas (woody vines) in forest regeneration, species diversity and ecosystem-level processes, particularly in the tropics. Mechanisms responsible for the maintenance of liana species diversity could yield new insights into the maintenance of overall species diversity. Lianas contribute to forest regeneration and competition, not only by competing directly with trees, but also by differentially affecting tree species and thus changing how trees compete among themselves. In addition, they contribute considerably to ecosystem-level processes, such as whole-forest transpiration and carbon sequestration. As the rate of tropical forest disturbance increases, they are likely to …

Where Have All The Voices Gone? A Case Study In Marginalization Politics At The Robert J. Bernard Field Station Of The Claremont Colleges, Yamini Bala

Pomona Senior Theses

This thesis is not intended to be an indictment of our leaders — well, not entirely, anyway.

This thesis is meant to be an exercise in listening. I talked to a lot of people on every side of this issue, and tried hard to listen. I obviously have my biases, but I did my best to understand where everyone was coming from. I tried to evaluate groups instead of individuals as participants in this issue. My interviewees were requested to express views on behalf of the community group to which they belonged. I tried to find the opinions that best …

Plant Conservation In The Juan Fernandez Archipelago, Chile, Tod F. Stuessy, Ulf Swenson, Daniel J. Crawford, Gregory Anderson, Mario Silva O.

Aliso: A Journal of Systematic and Floristic Botany

Oceanic archipelagos often hold very specialized floras with high degrees of endemism. These floras are frequently highly vulnerable to disturbance by natural causes and human intervention. The Juan Fernandez Islands (Chile) in the Pacific Ocean are a small archipelago of only three islands. Since discovery in 1574 by Juan Fernandez, human activities have altered floristic composition and survival circumstances of the endemic species. In this paper we document past and present means of disturbance, both anthropogenic and natural, which have influenced the native vegetation. The most destructive past activities have been logging and .introduction of animals and plants, both deliberately …

Conservation And Indigenous Human Land Use In The Río Plátano Watershed, Northeast Honduras, Jeffery W. Froehlich, Karl H. Schwerin

Research Papers

"In terms of volume and potential impact, the most serious conservation problem in the world today is the destruction of lowland tropical forests and the extinction of their fauna. Since 1950, according to the Food and Agriculture Organization, half of the world's forests have vanished (Cultural Survival, Inc., 1982). The conversion rate of these forests is currently so great that a recent National Research Council (1980a) panel has predicted that their existence as a natural ecosystem will cease by the year 2000, except perhaps in two areas - Western Amazonia and Central Africa. One important step toward the preservation of …