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Arroyo Toad (Anaxyrus californicus) Life History, Population Status, Population Threats, and Habitat Assessment of Conditions at Fort Hunter Liggett, Monterey County, CaliforniaHancock, Jacquelyn Petrasich 01 December 2009 (has links) (PDF)
The arroyo toad (Anaxyrus californicus) is a federally endangered species found on Fort Hunter Liggett, Monterey County, California. The species was discovered in 1996 and was determined to occupy 26.7 km of the San Antonio River from approximately 2.4 km northwest of the San Antonio Mission de Padua, to the river delta above the San Antonio Reservoir. The construction of the San Antonio Reservoir dam in 1963 isolated this northern population of arroyo toads. Through time, the Fort Hunter Liggett landscape has changed drastically. The land was heavily grazed by cattle until 1991, which considerably reduced vegetation in riparian areas. Military training following acquisition of the land in 1940 far exceeded current allowable training. Fire was used extensively to reduce unfavorable vegetation, and as a result, extreme tree loss occurred through the ranges. Today cattle grazing is prohibited and military activity is restricted from riparian corridors. While riparian vegetation continues to recover in the San Antonio River, habitat for breeding arroyo toads has become less suitable. To improve conservation efforts and management of this endangered species, I have provided a thorough assessment of the life history of arroyo toads specific to Fort Hunter Liggett and identified the status and current threats to the population on the installation. I have also prepared a habitat assessment of the San Antonio River in the arroyo toad range, quantified habitat conversion, and identified areas that may no longer provide suitable breeding habitat for the species. The research conducted for this report is preliminary to restoration efforts that are inevitable to ensure recovery of the endangered species at Fort Hunter Liggett.
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Assessing and improving the efficacy of BREEAM in relation to ecologyKirkpatrick, Jon January 2010 (has links)
The loss of ecological integrity as a result of urban spread and construction threatens the overall biodiversity of urban areas and prompts us to consider means of better including ecological biodiversity within development projects. The UK’s best practice tool for ensuring the integration of ecology into such projects is the Building Research Establishments Environmental Assessment Method (BREEAM). This thesis seeks to identify the efficacy of the current approach to ecological integration within BREEAM, and enable development to foster biodiversity and ecology more positively in the urban environment. Qualitative and quantitative research techniques were used to develop a new approach to the integration of ecology within an existing and nationally recognised model. This began by exploring the efficacy of and the main flaws in the present system by a survey of ecologists with experience of the BREEAM process. This led to a new approach to establishing the ecological value of urban ecology utilising a new calculation methodology, adapting the current scheme to focus on land use change as a result of urban land use planning and development. This new approach utilises habitat changes at its core to measure positive and negative change and indicate potential design solutions in land use planning within a development. The innovative methodology was tested using an in depth case study to review and discuss its effective application. The outcome was a new way to address the important variables of habitat integration and linkages maintaining ecological integrity and provision of ecosystem services. It is considered that the outlined approach of the new Land Use and Ecology section of BREEAM is suitable for integration into the next iteration in 2010, which will enable development to positively foster biodiversity and ecology in the urban environment.
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Fish-Habitat Associations in a Large Dryland River of the Murray-Darling Basin, AustraliaBoys, Craig Ashley, n/a January 2007 (has links)
Many aspects concerning the association of riverine fish with in-channel habitat remain
poorly understood, greatly hindering the ability of researchers and managers to address
declines in fish assemblages. Recent insights gained from landscape ecology suggest
that small, uni-scalar approaches are unlikely to effectively determine those factors that
influence riverine structure and function and mediate fish-habitat associations. There
appears to be merit in using multiple-scale designs built upon a geomorphologically-derived
hierarchy to bridge small, intermediate and large spatial scales in large rivers.
This thesis employs a hierarchical design encompassing functional process zones
(referred to hereafter as zones), reaches and mesohabitats to investigate fish-habitat
associations as well as explore patterns of in-channel habitat structure in one of
Australia's largest dryland river systems; the Barwon-Darling River.
In this thesis, empirical evidence is presented showing that large dryland rivers are
inherently complex in structure and different facets of existing conceptual models of
landscape ecology must be refined when applied to these systems. In-channel habitat
and fish exist within a hierarchical arrangement of spatial scales in the riverscape,
displaying properties of discontinuities, longitudinal patterns and patch mosaics. During
low flows that predominate for the majority of time in the Barwon-Darling River there
is a significant difference in fish assemblage composition among mesohabitats. There is
a strong association between large wood and golden perch, Murray cod and carp, but
only a weak association with bony herring. Golden perch and Murray cod are large
wood specialists, whereas carp are more general in there use of mesohabitats. Bony
herring are strongly associated with smooth and irregular banks but are ubiquitous in
most mesohabitats. Open water (mid-channel and deep pool) mesohabitats are
characterised by relatively low abundances of all species and a particularly weak
association with golden perch, Murray cod and carp. Murray cod are weakly associated
with matted bank, whereas carp and bony herring associate with this mesohabitat patch
in low abundance.
Nocturnal sampling provided useful information on size-related use of habitat that was
not evident from day sampling. Both bony herring and carp exhibited a variety of
habitat use patterns throughout the die1 period and throughout their lifetime, with
temporal partitioning of habitat use by juvenile bony herring and carp evident. Much of
the strong association between bony herring and smooth and irregular banks was due to
the abundance of juveniles (<100mm in length) in these mesohabitats. Adult bony
herring (>100mm length) occupied large wood more than smooth and irregular banks.
At night, juvenile bony herring were not captured, suggesting the use of deeper water
habitats. Adult bony herring were captured at night and occupjed large wood, smooth
bank and irregular bank. Juvenile carp (<200mm length) were more abundant at night
and aggregated in smooth and irregular banks more than any other mesohabitat patch.
Adult carp (>200mm length) occupied large wood during both day and night.
There is a downstream pattern of change in the fish assemblage among river zones, with
reaches in Zone 2 containing a larger proportion of introduced species (carp and
goldfish) because of a significantly lower abundance of native species (bony herring,
golden perch and Murray cod) than all other zones. In comparison, the fish assemblage
of Zone 3 was characterised by a comparatively higher abundance of the native species
bony herring, golden perch and Murray cod. A significant proportion of the amongreach
variability in fish assemblage composition was explained at the zone scale,
suggesting that geomorphological influences may impose some degree of top-down
constraint over fish assemblage distribution. Although mesohabitat composition among
reaches in the Barwon-Darling River also changed throughout the study area, this
pattern explained very little of the large-scale distribution of the fish assemblage, with
most of the variability in assemblage distribution remaining unexplained. Therefore,
although mesohabitat patches strongly influence the distribution of species within
reaches, they explain very little of assemblage composition at intermediate zone and
larger river scales. These findings suggest that small scale mesohabitat rehabilitation
projects within reaches are unlikely to produce measurable benefits for the fish
assemblage over intermediate and large spatial scales in the Barwon-Darling River. This
indicates the importance taking a holistic approach to river rehabilitation that correctly
identifies and targets limiting processes at the correct scales.
The variable nature of flow-pulse dynamics in the Barwon-Darling River creates a
shifting habitat mosaic that serves to maintain an ever-changing arrangement of habitat
patches. The inundation dynamics of large wood habitat described in this thesis
highlights the fragmented nature of mesohabitat patches, with the largest proportion of
total in-channel large wood remaining unavailable to fish for the majority of the time.
At low flows there is a mosaic of large wood habitat and with increasing discharge more
potential large wood habitat becomes available and does so in a complex spatial
manner. What results in this dryland river is a dynamic pattern of spatio-temporal
patchiness in large wood habitat availability that is seen both longitudinally among
different river zones and vertically among different heights in the river channel. Water
resource development impacts on this shifting habitat mosaic.
Projects undertaking both fish habitat assessment and rehabilitation need to carefully
consider spatial scale since the drivers of fish assemblage structure can occur at scales
well beyond that of the reach. Fish-habitat associations occurring at small spatial scales
can become decoupled by process occurring across large spatial scales, making
responses in the fish assemblage hard to predict. As rivers become increasingly
channelised, there is an urgent need to apply research such as that conducted in this
thesis to better understand the role that in-channel habitats play in supporting fish and
other ecosystem processes. Habitat rehabilitation projects need to be refined to consider
the appropriate scales at which fish assemblages associate with habitat. Failure to do so
risks wasting resources and forgoes valuable opportunities for addressing declines in
native fish populations. Adopting multi-scalar approaches to understanding ecological
processes in aquatic ecosystems, as developed in this thesis, should be a priority of
research and management. To do so will enable more effective determination of those
factors that influence riverine structure and function at the approariate scale.
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Detecting Change in Central California Coast Coho Salmon Habitat in Scotts Creek, California, from 1997–2013Hillard, Ashley Brubaker 01 June 2015 (has links)
Scotts Creek, in Santa Cruz County, Calif., supports the southernmost extant population of Coho Salmon (Oncorhynchus kisutch) in North America. In 1997, the California Department of Fish and Game (now Fish and Wildlife) conducted an extensive habitat typing survey of mainstem Scotts Creek, describing all habitat units from the top of the estuary to the limit of anadromy approximately 12 km upstream. I repeated this survey in 2013 to (1) assess changes in the quantity and quality of instream habitat, (2) compare the current condition to goals and standards established in the federal Central California Coast (CCC) Coho Salmon Recovery Plan, and (3) identify opportunities for possible future restoration. A comparison of the two surveys revealed an overall increase in mean canopy cover, mean bank vegetation, mean percentage instream cover, pool depth diversity, and percentage riffles since 1997, and decreases in mean residual pool depth, percentage flatwater, and number of primary pools. Overall, the percentage of the total mainstem classified as pool habitat did not change between the two survey periods. Results for individual habitat metrics were more variable when the stream was broken into discrete reaches delineated by major tributary junctions. Although a large woody debris (LWD) survey was not conducted as part of the 1997 survey, contrasting our results with data collected during intervening years indicated that instream LWD has become more abundant, primarily due to increases in hard-wood species (i.e., red alder [Alnus rubra] and California bay [Umbellularia californica]). When compared to habitat goals established in the federal CCC Coho Salmon Recovery Plan, Scotts Creek has adequate canopy cover and percentage pools, but is lacking in percentage riffles, instream cover, key pieces of LWD per100 m, and percentage primary pools.
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Quantifying Forest Vertical Structure to Determine Bird Habitat Quality in the Greenbelt Corridor, Denton, TxMatsubayashi, Shiho 08 1900 (has links)
This study presents the integration of light detection and range (LiDAR) and hyperspectral remote sensing to create a three-dimensional bird habitat map in the Greenbelt Corridor of the Elm Fork of the Trinity River. This map permits to examine the relationship between forest stand structure, landscape heterogeneity, and bird community composition. A biannual bird census was conducted at this site during the breeding seasons of 2009 and 2010. Census data combined with the three-dimensional map suggest that local breeding bird abundance, community structure, and spatial distribution patterns are highly influenced by vertical heterogeneity of vegetation surface. For local breeding birds, vertical heterogeneity of canopy surface within stands, connectivity to adjacent forest patches, largest forest patch index, and habitat (vegetation) types proved to be the most influential factors to determine bird community assemblages. Results also highlight the critical role of secondary forests to increase functional connectivity of forest patches. Overall, three-dimensional habitat descriptions derived from integrated LiDAR and hyperspectral data serve as a powerful bird conservation tool that shows how the distribution of bird species relates to forest composition and structure at various scales.
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The Effects of Microhabitat and Land Use on Stream Salamander Occupancy and Abundance in the Southwest Virginia CoalfieldsSweeten, Sara 09 April 2015 (has links)
Large-scale land uses such as residential wastewater discharge and coal mining practices, particularly surface coal extraction and associated valley fills, are of particular ecological concern in central Appalachia. Identification and quantification of both large-scale land use and microhabitat alterations to ecosystems are a necessary first-step aid in mitigation of negative consequences to biota. In central Appalachian headwater streams absent of fish, salamanders are the dominant, most abundant vertebrate predator providing a significant intermediate trophic role. Stream salamander species are considered to be sensitive to aquatic stressors and environmental alterations with past research having shown linkages among microhabitat parameters, and large-scale land use such as urbanization and logging to salamander abundances. However, there is little information examining these linkages in the coalfields of central Appalachia. In the summer of 2013, I visited 70 sites (sampled three times each) in the southwest Virginia coalfields to collect salamanders and quantify stream and riparian microhabitat parameters. In an information-theoretic framework I compared the effects of microhabitat and large-scale land use on salamander occupancy and abundances. My findings indicate that dusky salamander (Desmognathus spp.) occupancy and abundances are more correlated to microhabitat parameters such as canopy cover than to subwatershed land uses. Brook salamander (Eurycea spp.) occupancy show negative associations to large-scale land uses such as percent recent mining and percent forested. Whereas Eurycea spp. abundances are negatively influenced by suspended sediments, stream bank erosion and stream substrate embeddedness. Management implications of these findings include erosion prevention and control as well as protection and management of riparian habitats. However, quantifying physical environmental quality such as stream and riparian habitat often can be quite difficult, particularly when there are time or fiscal limitations. In order to accurately assess stream and riparian habitat in a time- and cost- effective manner, the U.S. Army Corps of Engineers (USACE) developed a functional condition index (FCI) assessment for streams that measures 11 stream and riparian parameters along with watershed land use to calculate three different scores: a hydrology score, biogeochemical score, and habitat score (Noble et al 2010). Using the salamander data from 2013, I then analyzed the FCI scores using collected occupancy and abundance analyses. Both analyses supported the Habitat FCI score as it had strong correlations with both occupancy and abundance of three Desmognathus spp., and support the use of the USACE protocol for stream and riparian habitat assessment. / Ph. D.
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Effects of Cattle Exclusion on Stream Habitat in the Shenandoah Valley, VirginiaPrice, Kendall Susan 29 May 2012 (has links)
Cattle exclusion from streams is believed to improve riparian vegetation, in-stream habitat, and composition of aquatic organisms. Yet research on the effects of cattle exclusion have yielded conflicting results. The goal of this study was to examine relationships between physical habitat and benthic macroinvertebrate populations with increasing downstream distance from cattle-impacted stream segments, and determine which physical habitat and chemical water quality parameters are affected by cattle presence. Macroinvertebrates from 24 sites in Rockingham County, VA were used to calculate bioassessment metrics. Fourteen sites made up 4 longitudinal studies where improvement of biotic condition with distance from cattle impact was examined. Linear regression and multilevel modeling results indicated improving macroinvertebrate assemblage with increasing distance downstream from cattle-impacted reaches. Presence of riparian trees and distance from impact had a positive influence on bioassessment scores. A total of 39 stream sites in the Shenandoah Valley were classified using the Rapid Habitat Assessment (RHA) which is based on 10 visual evaluations of physical characteristics. Four of the ten RHA parameters, embeddedness, bank stability, vegetative protection, and riparian vegetative zone width, along with the total RHA score, were associated with cattle presence. This study found that a) RHA factors reflect direct cattle impacts on the riparian zone, but RHA has limitations as a general predictor of cattle impact, b) cattle influence on benthic macroinvertebrates extends hundreds of meters beyond the immediate pasture boundary, and c) improvement in Virginia Stream Condition Index can be predicted as a function of distance downstream. / Master of Science
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Dopad úpravy území bývalého tankodromu na jeho ekosystémové služby / Impact of the adjustment of the area of former tank training area on its ecosystem servicesPAČKA, Jiří January 2013 (has links)
The ecological value and the value of ecosystem services of the former military area in Čtyři Dvory in České Budějovice was evaluated in this thesis. The expert method of BVM (?Biotope Valuation Method?) and the Replacement Cost method (cost of technological alternative to ecosystem function) according to Seják et al. (2003, 2010) were applied. Four ecosystem services were evaluated: climatic service (evapotranspiration), little water cycle, oxygen production, and the support of biodiversity. For comparison, the sale price of the area and the ?recreation? value calculated by the contingent valuation (CV) method were also evaluated. The estimated sale price was 837 million CZK, which was by twelve-times higher than the ecological value estimated by the BVM method. Most of the area (57 %) was formed by the biotop XK4 ? pioneer shrub vegetation of atropogenic noncultivated areas with 13 points per m2. The most valuable biotop was V2.2 ? periodic waters with 44 points per m2, which formed 1.5 % of the examined area. The estimated value of ecosystem services was 1 372 millions CZK per year. The realization of all the planned construction projects on the examined area would lead to the depression of the ecological value according to the BVM method by 19.5 millions CZK and the depression of the value of the formerly mentioned four ecosystem services by 459 millions CZK.
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Living on the Edge: An Assessment of Habitat Disturbance and Primate Use on the Osa Peninsula, Costa RicaSkrinyer, Andrew John 03 May 2016 (has links)
No description available.
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Landscape pattern analysis related to forest wildlife resourcesTrani, Margaret Katherine 06 June 2008 (has links)
Wildlife management and natural resource policy decisions are increasingly being made at the landscape level. Understanding the relationship between modification and the pattern of land classes may minimize potential impacts and enhance the complement of wildlife species.
Twenty-four expressions were selected for landscape analysis that describe the spatial heterogeneity, fragmentation, edge characteristics, and connectivity of pattern. Metric relationships were characterized across a variety of landscapes. Cluster analysis organized the metrics into classes quite different from the classification categories used in the literature. Cluster membership reflected the number of land classes, the amount and distribution of forest cover, number of forest patches, patch position, patch shape, patch radius, and edge length.
Cartographic modeling was used to determine how modification influenced landscape pattern. The models depicted spatial relationships resulting from proposed landscape changes. Timber harvest schemes with a few large units and those in clustered arrangements led to less fragmentation than those schemes with several small units or those dispersed across the landscape. The placement of roads had either an invasive or partitioning effect on landscape pattern.
Discriminant analysis rated the effectiveness of pattern expressions for environmental assessment. Metric effectiveness differed among the timber harvest, road expansion, and deforestation modification schemes. The utility and limitations of each expression was discussed.
Sensitivity analyses examined the effects of changing spatial scale on pattern description. Scale influence was dependent upon landscape complexity, distribution of land classes, and the size and shape of those classes. The loss of ability to detect localized variability, to differentiate among spatial patterns, and to represent boundary detail accompanied the use of large pixels (420m²). There was evidence that spatial scale influences habitat evaluation. Semivariogram analysis assessed the constancy of expression behavior during changes in scale and presented the limits of tolerance for using large pixels in pattern analyses. The variability observed suggested that pattern misrepresentation occurred at coarse resolution levels.
The successful application of landscape analysis depends on the ability to quantify pattern. By analyzing and understanding selected aspects of landscape pattern, I have examined how wildlife management can be enhanced through a knowledge of the landscape. / Ph. D.
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