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J.L. Carter

Publications and source records attributed to J.L. Carter.

18 recordsLinked to original sources

Associations of stream geomorphic conditions and prevalence of alternative reproductive tactics among sockeye salmon populations

In many species, males may exhibit alternative life histories to circumvent the costs of intrasexual competition and female courtship. While the evolution and underlying genetic and physiological mechanisms behind alternative reproductive tactics are well studied, there has been less consideration of the ecological factors that regulate their prevalence. Here, we examine six decades of age composition records from thirty‐six populations of sockeye salmon ( Oncorhynchus nerka ) to quantify associations between spawning habitat characteristics and the prevalence of precocious sneakers known as ‘jacks’. Jack prevalence was independent of neutral genetic structure among stream populations, but varied among habitat types and as a function of continuous geomorphic characteristics. Jacks were more common in streams relative to beaches and rivers, and their prevalence was negatively associated with stream width, depth, elevation, slope and area, but positively related to bank cover. Behavioural observations showed that jacks made greater use of banks, wood and shallows than guard males, indicating that their reproductive success depends on the availability of such refuges. Our results emphasize the role of the physical habitat in shaping reproductive tactic frequencies among populations, likely through local adaptation in response to variable fitness expectations under different geomorphic conditions.

Journal of Evolutionary Biology↗

Calculation of weighted averages approach for the estimation of ping tolerance values

A biotic index was created and proposed as a tool to assess water quality in the Upper Mae Ping sub-watersheds. The Ping biotic index was calculated by utilizing Ping tolerance values. This paper presents the calculation of Ping tolerance values of the collected macroinvertebrates. Ping tolerance values were estimated by a weighted averages approach based on the abundance of macroinvertebrates and six chemical constituents that include conductivity, dissolved oxygen, biochemical oxygen demand, ammonia nitrogen, nitrate nitrogen and orthophosphate. Ping tolerance values range from 0 to 10. Macroinvertebrates assigned a 0 are very sensitive to organic pollution while macroinvertebrates assigned 10 are highly tolerant to pollution.

Chiang Mai Journal of Science↗

Assessment tools for urban catchments: developing biological indicators based on benthic macroinvertebrates

Biological indicators, particularly benthic macroinvertebrates, are widely used and effective measures of the impact of urbanization on stream ecosystems. A multimetric biological index of urbanization was developed using a large benthic macroinvertebrate dataset (n = 1,835) from the Baltimore, Maryland, metropolitan area and then validated with datasets from Cleveland, Ohio (n = 79); San Jose, California (n = 85); and a different subset of the Baltimore data (n = 85). The biological metrics used to develop the multimetric index were selected using several criteria and were required to represent ecological attributes of macroinvertebrate assemblages including taxonomic composition and richness (number of taxa in the insect orders of Ephemeroptera, Plecoptera, and Trichoptera), functional feeding group (number of taxa designated as filterers), and habit (percent of individuals which cling to the substrate). Quantile regression was used to select metrics and characterize the relationship between the final biological index and an urban gradient (composed of population density, road density, and urban land use). Although more complex biological indices exist, this simplified multimetric index showed a consistent relationship between biological indicators and urban conditions (as measured by quantile regression) in three climatic regions of the United States and can serve as an assessment tool for environmental managers to prioritize urban stream sites for restoration and protection.

Journal of the American Water Resources Associatio↗

Benthic nutrient sources to hypereutrophic Upper Klamath Lake, Oregon, USA

Three collecting trips were coordinated in April, May, and August 2006 to sample the water column and benthos of hypereutrophic Upper Klamath Lake (OR, USA) through the annual cyanophyte bloom of Aphanizomenon flos‐aquae . A pore‐water profiler was designed and fabricated to obtain the first high‐resolution (centimeter‐scale) estimates of the vertical concentration gradients of macro‐ and micronutrients for diffusive‐flux determinations. A consistently positive benthic flux for soluble reactive phosphorus (SRP) was observed with solute release from the sediment, ranging between 0.4 and 6.1 mg/m 2 /d. The mass flux over an approximate 200‐km 2 lake area was comparable in magnitude to riverine inputs. An additional concern related to fish toxicity was identified when dissolved ammonium also displayed consistently positive benthic fluxes of 4 to 134 mg/m 2 /d, again comparable to riverine inputs. Although phosphorus was a logical initial choice by water quality managers for the limiting nutrient when nitrogen‐fixing cyanophytes dominate, initial trace‐element results from the lake and major inflowing tributaries suggested that the role of iron limitation on primary productivity should be investigated. Dissolved iron became depleted in the lake water column during the course of the algal bloom, while dissolved ammonium and SRP increased. Elevated macroinvertebrate densities, at least of the order of 10 4 individuals/m 2 , suggested that the diffusive‐flux estimates may be significantly enhanced by bioturbation. In addition, heat‐flux modeling indicated that groundwater advection of nutrients could also significantly contribute to internal nutrient loading. Accurate environmental assessments of lentic systems and reasonable expectations for point‐source management require quantitative consideration of internal solute sources.

Environmental Toxicology and Chemistry↗

Development of a local-scale urban stream assessment method using benthic macroinvertebrates: An example from the Santa Clara Basin, California

Research that explores the biological response to urbanization on a site-specific scale is necessary for management of urban basins. Recent studies have proposed a method to characterize the biological response of benthic macroinvertebrates along an urban gradient for several climatic regions in the USA. Our study demonstrates how this general framework can be refined and applied on a smaller scale to an urbanized basin, the Santa Clara Basin (surrounding San Jose, California, USA). Eighty-four sampling sites on 14 streams in the Santa Clara Basin were used for assessing local stream conditions. First, an urban index composed of human population density, road density, and urban land cover was used to determine the extent of urbanization upstream from each sampling site. Second, a multimetric biological index was developed to characterize the response of macroinvertebrate assemblages along the urban gradient. The resulting biological index included metrics from 3 ecological categories: taxonomic composition ( Ephemeroptera, Plecoptera, and Trichoptera), functional feeding group (shredder richness), and habit ( clingers). The 90 th -quantile regression line was used to define the best available biological conditions along the urban gradient, which we define as the predicted biological potential. This descriptor was then used to determine the relative condition of sites throughout the basin. Hierarchical partitioning of variance revealed that several site-specific variables (dissolved O 2 and temperature) were significantly related to a site's deviation from its predicted biological potential. Spatial analysis of each site's deviation from its biological potential indicated geographic heterogeneity in the distribution of impaired sites. The presence and operation of local dams optimize water use, but modify natural flow regimes, which in turn influence stream habitat, dissolved O 2 , and temperature. Current dissolved O 2 and temperature regimes deviate from natural conditions and appear to affect benthic macroinvertebrate assemblages. The assessment methods presented in our study provide finer-scale assessment tools for managers in urban basins. ?? North American Benthological Society.

Journal of the North American Benthological Societ↗

Earliest report of the genus Phyricodothyris George (Brachiopoda: Reticularioidea) in North America

Described from the Wymps Gap Member of the Mauch Chunk Formation of southwestern Pennsylvania and adjacent Maryland is a new species, Phyricodothyris lauriegrahamae, of the Upper Mississippian reticulariod brachiopod Phyricodothyris George, 1932. The Wymps Gap Limestone from which the type material was collected is middle Chesterian (late Visdan) in age. This is the first report of this genus from confirmed Mississippian rocks in North America.

Annals of Carnegie Museum↗

Effects of copper on composition species of periphyton in a Sierra Nevada, California, stream

An oligotrophic stream was continuously dosed for 1 yr at 2.5, 5 and 10 mu g l-1 CuT; c12, 25 and 50 ng l-1 Cu2+. The numerically most abundant taxa were Bacillariophyceae (Achnanthes minutissima, Cocconeis placentula, Cymbella microcephala, C. sinuata, Fragilaria construens, F. crotonensis, Navicula spp., Synedra acus and S. rumpens), and the Cyanophyta Lyngbya spp., a co-dominant during spring and summer. Population densities of Lyngbya spp. were markedly reduced at all Cu concentrations. Population densities of the principal Chlorophyta (Spirogyra spp., Cladophora spp.) and the diatom Amphipleura pellucida were reduced at 5 mu g l-1 CuT. Of the 22 most abundant taxa, 16 were reduced in abundance by continuous exposure to 10 mu g l-1 CuT. There was no commensurate reduction in standing crop. Achnanthes minutissima was the primary replacement species. Other taxa more abundant at 5 mu g l-1 CuT than in the control were Ceratoneis arcus, Cocconeis placentula, Navicula spp. and Synedra rumpens. Only A. minutissima and Calothrix spp. were more abundant at 10 mu g l-1 than in the control. Three resemblance measures (Canberra metric, Bray-Curtis and Dice) and diversity (Brillouin's) were evaluated for detecting differences in species composition among stream sections. The Canberra metric, an index sensitive to proportional rather than absolute differences, was the most informative.

Freshwater Biology↗

A method for the use of landscape metrics in freshwater research and management

Freshwater research and management efforts could be greatly enhanced by a better understanding of the relationship between landscape-scale factors and water quality indicators. This is particularly true in urban areas, where land transformation impacts stream systems at a variety of scales. Despite advances in landscape quantification methods, several studies attempting to elucidate the relationship between land use/land cover (LULC) and water quality have resulted in mixed conclusions. However, these studies have largely relied on compositional landscape metrics. For urban and urbanizing watersheds in particular, the use of metrics that capture spatial pattern may further aid in distinguishing the effects of various urban growth patterns, as well as exploring the interplay between environmental and socioeconomic variables. However, to be truly useful for freshwater applications, pattern metrics must be optimized based on characteristic watershed properties and common water quality point sampling methods. Using a freely available LULC data set for the Santa Clara Basin, California, USA, we quantified landscape composition and configuration for subwatershed areas upstream of individual sampling sites, reducing the number of metrics based on: (1) sensitivity to changes in extent and (2) redundancy, as determined by a multivariate factor analysis. The first two factors, interpreted as (1) patch density and distribution and (2) patch shape and landscape subdivision, explained approximately 85% of the variation in the data set, and are highly reflective of the heterogeneous urban development pattern found in the study area. Although offering slightly less explanatory power, compositional metrics can provide important contextual information.

Landscape Ecology↗

Setting limits: The development and use of factor-ceiling distributions for an urban assessment using macroinvertebrates

Lotic habitats in urban settings are often more modified than in other anthropogenically influenced areas. The extent, degree, and permanency of these modifications compromise the use of traditional reference-based study designs to evaluate the level of lotic impairment and establish restoration goals. Directly relating biological responses to the combined effects of urbanization is further complicated by the nonlinear response often observed in common metrics (e.g., Ephemeroptera, Plecoptera, and Trichoptera [EPT] species richness) to measures of human influence (e.g., percentage urban land cover). A characteristic polygonal biological response often arises from the presence of a generalized limiting factor (i.e., urban land use) plus the influence of multiple additional stressors that are nonuniformly distributed throughout the urban environment. Benthic macroinvertebrates, on-site physical habitat and chemistry, and geographical information systems-derived land cover data for 85 sites were collected within the 1,600-km2 Santa Clara Valley (SCV), California urban area. A biological indicator value was derived from EPT richness and percentage EPT. Partitioned regression was used to define reference conditions and estimate the degree of site impairment. We propose that an upper-boundary condition (factor-ceiling) modeled by partitioned regression using ordinary least squares represents an attainable upper limit for biological condition in the SCV area. Indicator values greater than the factor-ceiling, which is monotonically related to existing land use, are considered representative of reference conditions under the current habitat conditions imposed by existing land cover and land use.

American Fisheries Society Symposium↗

Relationships of field habitat measurements, visual habitat indices, and land cover to benthic macroinvertebrates in urbanized streams of the Santa Clara Valley, California

We evaluated several approaches for measuring natural and anthropogenic habitat characteristics to predict benthic macroinvertebrate assemblages over a range of urban intensity at 85 stream sites in the Santa Clara Valley, California. Land cover was summarized as percentage urban land cover and impervious area within upstream buffers and the upstream subwatersheds. Field measurements characterized water chemistry, channel slope, sediment, and riparian canopy. In . addition to applying the visual-based habitat assessment in U.S. Environmental Protection Agency's rapid bioassessment protocol, we developed a simplified urban habitat assessment index based on turbidity, fine sediment deposition, riparian condition, and channel modification. Natural and anthropogenic habitat variables covaried along longitudinal stream gradients and were highly correlated with elevation. At the scale of the entire watershed, benthic macroinvertebrate measures were equally correlated with variables expressing natural gradients and urbanization effects. When natural gradients were reduced by partitioning sites into ecoregion subsection groupings, habitat variables most highly correlated with macroinvertebrate measures differed between upland and valley floor site groups. Among the valley floor sites, channel slope and physical modification of channel and riparian habitats appeared more important than upstream land cover or water quality in determining macroinvertebrate richness and ordination scores. Among upland sites, effects of upstream reservoir releases on habitat quality appeared important. Rapid habitat evaluation methods appeared to be an effective method for describing habitat features important to benthic macroinvertebrates when adapted for the region and the disturbance of interest. ?? 2005 by the American Fisheries Society.

American Fisheries Society Symposium↗

The relationships among three habitat scales and stream benthic invertebrate community structure

1. The relationships between three habitat scales and lotic invertebrate species composition were investigated for the 15 540 km 2 Yakima River basin in south-central Washington, U.S.A. 2. The three spatial scales were sample (the sampled riffle), reach (a length of ten–twenty stream widths) and segment (a length of stream of nearly uniform slope and valley form having no change in stream order). 3. Physical variables were highly correlated between scales and expressed a relationship between altitude, basin form and small-scale physical structure. 4. Multiple discriminant function analyses indicated that segment- and reach-scale variables discriminated among species-defined groups better than sample-scale variables. 5. Species composition varied along a complex altitudinal gradient of changing basin form and resultant land use. 6. There was no clear relationship between species richness and altitude on a site basis. However, when viewed at the basin scale, maximum richness was observed at the transition between montane and valley sites.

Freshwater Biology↗

Importance of Sediment-Water Interactions in Coeur d'Alene Lake, Idaho, USA: Management Implications

A field study at Coeur d'Alene Lake, Idaho, USA, was conducted between October 1998 and August 2001 to examine the potential importance of sediment-water interactions on contaminant transport and to provide the first direct measurements of the benthic flux of dissolved solutes of environmental concern in this lake. Because of potential ecological effects, dissolved zinc and orthophosphate were the solutes of primary interest. Results from deployments of an in situ flux chamber indicated that benthic fluxes of dissolved Zn and orthophosphate were comparable in magnitude to riverine inputs. Tracer analyses and benthic-community metrics provided evidence that solute benthic flux were diffusion-controlled at the flux-chamber deployment sites. That is, effects of biomixing (or bioturbation) and ground-water interactions did not strongly influence benthic flux. Remediation efforts in the river might not produce desired water-quality effects in the lake because imposed shifts in concentration gradients near the sediment-water interface would generate a benthic feedback response. Therefore, development of water-quality models to justify remediation strategies requires consideration of contaminant flux between the water column and underlying sediment in basins that have been affected by long-term (decadal) anthropogenic activities.

Idaho↗

Inter-annual changes in the benthic community structure of riffles and pools in reaches of contrasting gradient

The inter-annual variation in the structure of the benthic community of riffles and pools was evaluated in contrasting geomorphic settings. The community structure of riffles and pools was a function of habitat, reach gradient, and discharge and was taxon specific. In years of below average peak discharge, riffles had higher taxon richness than pools (66 versus 47) but richness was similar between habitats during a year of average discharge (56 versus 54). The percentage composition of oligochaetes and elmid beetles was more variable inter-annually in pools and low gradient reaches than in high gradient reaches. Differences in the percentage of collector-gatherers and scrapers in riffles and pools appeared related to inter-annual differences in discharge regimes. Two components of the annual discharge regime appear to differentially affect the composition of the benthic community in the snowmelt dominated stream studied: the magnitude of the annual peak discharge and the duration and timing of the period of extended high flow.

Hydrobiologia↗

Aquatic insects as bioindicators of trace element contamination in cobble-bottom rivers and streams

In one river, Cu, Cd, Pb, and Zn were analysed in insects and in fine bed sediments over a 381-km reach downstream of a large copper mining complex. In another river, As contamination from a gold mine was assessed in insects and bed sediments over a 40-km reach. All insect taxa collected in contaminated river reaches had elevated whole-body trace element concentrations, but few species were distributed throughout the study reaches. Comparisons of contamination at taxomic levels higher than species were complicated by element-specific differences in bioaccumulation among taxa. These differences appeared to be governed by biological and hydrogeochemical factors. Variation in element concentrations among species of the caddisfly Hydropsyche was slightly greater than within individual species. If this genus is representative of others, comparisons of contamination within genera may be a practical alternative for biomonitoring studies when single species are not available.

Canadian Journal of Fisheries and Aquatic Sciences↗

A review of bufflehead sex and age criteria with notes on weights

Summary: Buftleheads Bucephala albeola were collected along the Oregon coast during the hunting season. Birds were first sexed and aged upon cloacal and internal characteristics. Results were then compared with data derived from wing plumage. A small change was made in Carney's (1964) wing plumage key to improve its accuracy. Although only a few studies have been made of Bufflehead weights, it seems that in at least several of these, some immature males have been included in the female category. This mistake has probably resulted from the extremely small penis in the immatures. The foot web length shows potential as a simple sexing criterion during the fall and winter for immatures which are the most difficult to sex under field conditions.

Wildfowl↗

Lunar metallic particle ("mini-moon"): An interpretation

A troilite-rich nickel-iron particle ("mini-moon") recovered from the moon may be a mound detached from a sphere of silicate glass. Erosion and pitting of the particle may have been caused by passage through a cloud of hot gas and particulate matter formed by meteorite impact on the lunar surface. This explanation is in contrast to the theory that the particle was meteoritically derived molten material that was furrowed during solidification after lunar impact, subsequently pitted by high-velocity particles, and then abraded and polished by drifting dust while on the lunar surface.

Science↗