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Linking BMPs to Receiving Water Impact Mitigation in Austin, TX
This report mentions how the water quality of upstream Waller Creek can affect downstream sites.Changes to receiving water bodies following Best Management Practices project (BMP) implementation were evaluated using the Environmental Integrity Index (EII). Data from five wet ponds and one channel restoration project were used. Changes in the six EII sub-indices (water quality, sediment quality, contact recreation, non-contact recreation, habitat quality and aquatic life support) were generally positive except for habitat quality, which declined initially but tended to recover. Water quality through wet pond sites improved by an average of 7%, and the channel erosion site improved water by 18%. Additional data collection is needed to strengthen conclusions.Waller Creek Working Grou
The importance of habitat quality for marine reserve fishery linkages
We model marine reserve - fishery linkages to evaluate the potential contribution of habitat-quality improvements inside a marine reserve to fish productivity and fishery catches. Data from Mombasa Marine National Park, Kenya, and the adjacent fishery are used. Marine reserves increase total fish biomass directly by providing refuge from exploitation and indirectly by improving fish habitat in the reserve. As natural mortality of the fish stock decreases in response to habitat enhancement in the reserve, catches increase by up to 2.6 tonnes (t).km(-2).year(-1) and total fish biomass by up to 36 t.km(-2). However, if habitat-quality improvement reduces the propensity of fish to move out of the reserve, catches may fall by up to 0.9 t.km(-2).year(-1). Our results indicate that habitat protection in reserves can underpin fish productivity and, depending on its effects on fish movements, augment catches
Bacon\u27s Swamp- Ghost of a Central Indiana Natural Area Past
Bacon’s Swamp was identified in the 1920s as a ca. 12 ha glacial kettle lake bog system at the southernmost limits of these habitats in Indiana. Located just 9.6 km from the center of Indianapolis, the site was all but destroyed in the mid-20th century by urban expansion. Prior to habitat conversion at the site, Bacon’s Swamp was a frequent location for Butler University ecology class field trips and student research projects. Herbarium specimens and published inventory records allow for analysis of the historical vegetation of Bacon’s Swamp using modern techniques. Floristic Quality Assessment applied to these historical records reveals Bacon’s Swamp was a regionally significant natural area, with a native Floristic Quality Index (FQI) value of 60 and a mean native Conservation Coefficient value of 4.2. Little of this unusual, high-quality habitat remains. A 2010 botanical inventory at the site documents decline in habitat with the loss of species that have a fidelity to high-quality habitat, with a corresponding drop in FQI to 20 and the addition of invasive non-native plants. Re-analysis of Bacon’s Swamp historical flora supports the view that it was a significant wetland natural area and floristically unique in Central Indiana
Fish Habitat Utilization Patterns and Evaluation of the Efficacy of Marine Protected Areas in Hawaii: Integration of NOAA Digital Benthic Habitat Mapping and Coral Reef Ecological Studies
Over the past four decades, the state of Hawaii has developed a system of eleven Marine Life Conservation Districts (MLCDs) to conserve and replenish marine resources around the state. Initially established to provide opportunities for public interaction with the marine environment, these MLCDs vary in size, habitat quality, and management regimes, providing an excellent opportunity to test hypotheses concerning marine protected area (MPA) design and function using multiple discreet sampling units. NOAA/NOS/NCCOS/Center for Coastal Monitoring and Assessment’s Biogeography Team developed digital benthic habitat maps for all MLCD and adjacent habitats. These maps were used to evaluate the efficacy of existing MLCDs for biodiversity conservation and fisheries replenishment, using a spatially explicit stratified random sampling design. Coupling the distribution of habitats and species habitat affinities using GIS technology elucidates species habitat utilization patterns at scales that are commensurate with ecosystem processes and is useful in defining essential fish habitat and biologically relevant boundaries for MPAs.
Analysis of benthic cover validated the a priori classification of habitat types and provided justification for using these habitat strata to conduct stratified random sampling and analyses of fish habitat utilization patterns. Results showed that the abundance and distribution of species and assemblages exhibited strong correlations with habitat types. Fish assemblages in the colonized and uncolonized hardbottom habitats were found to be most similar among all of the habitat types. Much of the macroalgae habitat sampled was macroalgae growing on hard substrate, and as a result showed similarities with the other hardbottom assemblages. The fish assemblages in the sand habitats were highly variable but distinct from the other habitat types.
Management regime also played an important role in the abundance and distribution of fish assemblages. MLCDs had higher values for most fish assemblage characteristics (e.g. biomass, size, diversity) compared with adjacent fished areas and Fisheries Management Areas (FMAs) across all habitat types. In addition, apex predators and other targeted resources species were more abundant and larger in the MLCDs, illustrating the effectiveness of these closures in conserving fish populations. Habitat complexity, quality, size and level of protection from fishing were important determinates of MLCD effectiveness with respect to their associated fish assemblages. (PDF contains 217 pages
Zannichellia contorta
This species is native to southern, central and eastern Spain, with an old record from the Atlas Mountains in northern Morocco requiring confirmation. The species is very sensitive to eutrophication and deterioration of water quality. The Area of Occupancy (AOO) has been estimated to be less than 500 km2 based on confirmed records and knowledge that its habitat is in continuous decline and at least 40% of the known localities have disappeared, especially in southern Spain. Moreover, an ongoing continuing decline in AOO, habitat quality and number of subpopulations of this species due to the increase in nutrients concentration from waters of the streams where it lives, which stops its growth, has been observed. The same process of habitat deterioration is happening in central and eastern Spain. The population of this species is severely fragmented with more than half of its subpopulations being isolated with no exchange possibilities and suspected to have reached no viable levels. It therefore qualifies to be listed in the category Endangered (EN B2ab(ii,iii,iv)) in the Mediterranean region. Resource and habitat protection and site management are needed. Other recommended conservation measures are ex situ conservation, population and distribution research, and habitat and population monitoring
Deer reduce habitat quality for a woodland songbird: evidence from settlement patterns, demographic parameters, and body condition.
Understanding avian responses to ungulate-induced habitat modification is important because deer populations are increasing across much of temperate Europe and North America. Our experimental study examined whether habitat quality for Blackcaps (Sylvia atricapilla) in young woodland in eastern England was affected by deer, by comparing Blackcap behavior, abundance, and condition between paired plots (half of each pair protected from deer). The vegetation in each pair of plots was the same age. The Blackcap is an ideal model species for testing effects of deer on avian habitat quality because it is dependent on dense understory vegetation and is abundant throughout much of Europe. We compared timing of settlement, abundance, age structure (second-year vs. after-second-year), and phenotypic quality (measured as a body condition index, body mass divided by tarsus length) between experimental and control plots. We used point counts to examine Blackcap distribution, and standardized mist netting to collect demographic and biometric data. Incidence of singing Blackcaps was higher in nonbrowsed than in browsed plots, and singing males were recorded in nonbrowsed plots earlier in the season, indicating earlier and preferential territory establishment. Most Blackcaps, both males and females, were captured in vegetation prior to canopy closure (2–4 years of regrowth). Body condition was superior for male Blackcaps captured in nonbrowsed plots; for second-year males this was most marked in vegetation prior to canopy closure. We conclude that deer browsing in young woodland can alter habitat quality for understory-dependent species, with potential consequences for individual fitness and population productivity beyond the more obvious effects on population density
Integration of technologies for understanding the functional relationship between reef habitat and fish growth and production
Functional linkage between reef habitat quality and fish growth and production has remained elusive. Most current research is focused on correlative relationships between a general habitat type and presence/absence of a species,
an index of species abundance, or species diversity. Such descriptive information largely ignores how reef attributes
regulate reef fish abundance (density-dependent habitat selection), trophic interactions, and physiological performance (growth and condition). To determine the
functional relationship between habitat quality, fish abundance, trophic interactions, and physiological performance, we are using an experimental reef system in
the northeastern Gulf of Mexico where we apply advanced sensor and biochemical technologies. Our study site controls for reef attributes (size, cavity space, and reef
mosaics) and focuses on the processes that regulate gag grouper (Mycteroperca microlepis) abundance, behavior and performance (growth and condition), and the availability of their pelagic prey. We combine mobile and fixed-active (fisheries) acoustics, passive acoustics, video cameras,
and advanced biochemical techniques. Fisheries acoustics quantifies the abundance of pelagic prey fishes associated
with the reefs and their behavior. Passive acoustics and video allow direct observation of gag and prey fish behavior and the acoustic environment, and provide a
direct visual for the interpretation of fixed fisheries acoustics measurements. New application of biochemical techniques, such as Electron Transport System (ETS) assay,
allow the in situ measurement of metabolic expenditure of gag and relates this back to reef attributes, gag behavior, and prey fish availability. Here, we provide an overview of our integrated technological approach for understanding and quantifying the functional relationship between reef habitat quality and one element of production – gag grouper growth on shallow coastal reefs
The impacts of natural flood management approaches on in-channel sediment quality
Natural Flood Management (NFM) techniques aim to reduce downstream flooding by storing and slowing the flow of stormwater to river channels. These techniques include a range of measures, including setback stormwater outfalls and the physical restoration of channels and floodplains, to improve the natural functioning of catchments. An additional benefit of NFM measures is the potential reduction in sediment and pollutant delivery to the channel. Urban development releases a variety of heavy metal and nutrient pollutants that enter rivers through stormwater outfalls with adverse effects on the aquatic ecosystem. In this study, the influence of channel modification and quality of the river habitat on the sediment quality surrounding stormwater outfalls was assessed. Sediment samples were taken at several outfalls within the Johnson Creek catchment, Oregon, USA, and analysed for a variety of urban pollutants. The level of river habitat quality and modification at each site were assessed using a semi-quantitative scoring methodology. Significant increases in pollutant levels were observed at outfalls, with a greater and more variable increase at direct compared to setback outfalls. Removal efficiency of certain pollutants was found to be significantly correlated to the level of habitat quality or modification (for Fe, Ba, Sn, Mg, P, K) indicating that more natural reaches had greater potential for pollutant removal. The findings highlight the multiple benefits associated with NFM and river restoration approaches in relation to sediment quality and pollutant content
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