Species versus generic identifications in water-quality monitoring and ecological studies of Trichoptera in North America: Is this question still unresolved after half a century?

Species-level identifications of the larval stages of caddisflies are available for only a limited number of taxa that are used currently in water-quality monitoring programs. This has been a long-lamented condition, but the proportion of species identifications available for aquatic forms that are used in these efforts has increased little over the past half-century. This is despite repeated and documented advantages that species-level identifications add to monitoring studies. Approaches to examining this question have ranged from anecdotal accounts of pollution tolerance among species within a genus to detailed analyses comparing information available through different hierarchical levels of taxonomy, from species to family. Justifications for not using species-level taxonomic resolution have ranged from financial considerations to suggestions that higher levels are equally as valid in showing trends as are species-level identifications. However, the evidence justifying the use of higher levels of taxonomy is lacking and more evidence favors the value of species-level identifications. Genetic techniques offer the promise of more larval-adult associations, more useful identification keys, and improved biological monitoring

Long-Term Variability in Bioassessments: A Twenty-Year Study from Two Northern California Streams

Long-term variability of bioassessments has not been well evaluated. We analyzed a 20-year data set (1984–2003) from four sites in two northern California streams to examine the variability of bioassessment indices (two multivariate RIVPACS-type O/E scores and one multimetric index of biotic integrity, IBI), as well as eight metrics. All sites were sampled in spring; one site was also sampled in summer. Variability among years was high for most metrics (coefficients of variation, CVs ranging from 16% to 246% in spring) but lower for indices (CVs of 22–26% for the IBI and 21–32% for O/E scores in spring), which resulted in inconsistent assessments of biological condition. Variance components analysis showed that the time component explained variability in all metrics and indices, ranging from 5% to 35% of total variance explained. The site component was large (i.e., >40%) for some metrics (e.g., EPT richness), but nearly absent from others (e.g., Diptera richness). Seasonal analysis at one site showed that variability among seasons was small for some metrics or indices (e.g., Coleoptera richness), but large for others (e.g., EPT richness, O/E scores). Climatic variables did not show consistent trends across all metrics, although several were related to the El Niño Southern Oscillation Index at some sites. Bioassessments should incorporate temporal variability during index calibration or include climatic variability as predictive variables to improve accuracy and precision. In addition, these approaches may help managers anticipate alterations in reference streams caused by global climate change and high climatic variability

The evolution of the sponge feeding habit in the caddisfly genus Ceraclea (Trichoptera, Leptoceridae)

A phylogeny is proposed for 11 species of Ceraclea caddisflies which feed on freshwater sponge during the larval stage of their life cycle. Based on this evolutionary scheme, further probable sponge feeders are postulated. Some morphological differences of the sponge feeders are described. The obligate sponge feeders are morphologically and ecologically different from other species of the genus which may feed on sponge when it is available or when other food sources are scarce, and from the species of Ceraclea which appear never to eat sponge

Author Sequence and Credit for Contributions in Multiauthored Publications

A transparent, simple, and straightforward approach that is free from any arbitrary rank valuation is required to estimate the credit associated with the sequence of authors' names on multiauthored papers

A Detailed Investigation of the Sociological, Economic, and Ecological Aspects of Proposed Reservoir Sites in the Salt River Basin of Kentucky

Samples of water, bottom fauna, and fishes were collected from 66 stations in the Salt River and one of its principal tributaries, the Beech Fork and its tributary, the Chaplin River, Kentucky. Precipitation ranged from 38.86 inches (1969) to 58.04 inches (1970), an increase of nearly 50 percent with marked fluctuations in discharge. Intensive comparisons of phosphates, sulfates, specific conductance, total alkalinity, total hardness, and turbidity showed the streams to be relatively clean and healthy. Nearly 300 different kinds of benthic organisms and other macroinvertebrates have been collected and identified from the basin. Detailed studies of caddisflies and stream drift are under way along with the development of computer programs for diversity indices of the various organisms. Twenty-eight species of bivalve mussels and representatives of six genera of snails have been collected including the Asiatic clam Corbicula mülleri. Among the vertebrates, 60 species of fishes have been collected and identified along with 22 amphibians and 21 reptiles. Nearly 150 species of birds have been identified in the area. An economic study of Spencer County revealed that there has been a decrease in the human population along with a general decline in the overall economic picture of the county as indicated by a retarded rate of growth in annual per capita income and a decline in total retail sales within the county over the past decade. The highway system in the county consists of largely Class 4, 5, and 6 roads which, because of the topography, are generally narrow, crooked, and hilly. However, Spencer County is almost completely encircled by interstate highways within ten miles of its borders

Changes in the Economy and Ecology at Proposed Lake Sites in the Salt River Basin, Kentucky, During Early Construction of the Dam for Taylorsville Lake

This is an extension of the work reported in Project numbers B-005-KY, B-016-KY, and B-022-KY that extended from 1 July 1968 through 30 June 1972. Permanent collecting stations have been established at 67 sites throughout the Salt River, Beech Fork, and Chaplin River drainages. Turbidities increases quickly as flow and runoff increase, and subside quickly when the rain stops. Suspended solids range up to 1,700 mg/l in high turbidities and vary considerably as a result of local spates. Water chemistry generally reflects the limestone nature of the substrate and physico-chemical characteristics of a typically healthy limestone stream. Bottom organisms are abundant and diverse, more than 300 different benthic organisms have been identified to date

Mediterranean-climate streams and rivers: geographically separated but ecologically comparable freshwater systems

Streams and rivers in mediterranean-climate regions (med-rivers in med-regions) are ecologically unique, with flow regimes reflecting precipitation patterns. Although timing of drying and flooding is predictable, seasonal and annual intensity of these events is not. Sequential flooding and drying, coupled with anthropogenic influences make these med-rivers among the most stressed riverine habitat worldwide. Med-rivers are hotspots for biodiversity in all med-regions. Species in med-rivers require different, often opposing adaptive mechanisms to survive drought and flood conditions or recover from them. Thus, metacommunities undergo seasonal differences, reflecting cycles of river fragmentation and connectivity, which also affect ecosystem functioning. River conservation and management is challenging, and trade-offs between environmental and human uses are complex, especially under future climate change scenarios. This overview of a Special Issue on med-rivers synthesizes information presented in 21 articles covering the five med-regions worldwide: Mediterranean Basin, coastal California, central Chile, Cape region of South Africa, and southwest and southern Australia. Research programs to increase basic knowledge in less-developed med-regions should be prioritized to achieve increased abilities to better manage med-rivers