Biological Monitoring Program Research Articles

The Role of Periphyton in Mediating the Effects of Pollution in a Stream Ecosystem

The effects of pollutants on primary producers ramify through ecosystems because primary producers provide food and structure for higher trophic levels and they mediate the biogeochemical cycling of nutrients and contaminants. Periphyton (attached algae) were studied as part of a long-term biological monitoring program designed to guide remediation efforts by the Department of Energy's Y-12 National Security Complex on East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee. High concentrations of nutrients entering EFPC were responsible for elevated periphyton production and placed the stream in a state of eutrophy. High rates of primary production at upstream locations in EFPC were associated with alterations in both invertebrate and fish communities. Grazers represented >50% of the biomass of invertebrates and fish near the Y-12 Complex but <10% at downstream and reference sites. An index of epilithic periphyton production accounted for 95% of the site-to-site variation in biomass of grazing fish. Analyses of heavy metals in EFPC periphyton showed that concentrations of zinc, cadmium, copper and nickel in periphyton decreased exponentially with distance downstream from Y-12. Zinc uptake by periphyton was estimated to reduce the concentration of this metal in stream water approximately 60% over a 5-km reach of EFPC. Management options for mitigating eutrophy in EFPC include additional reductions in nutrient inputs and/or allowing streamside trees to grow and shade the stream. However, reducing periphyton growth may lead to greater downstream transport of contaminants while simultaneously causing higher concentrations of mercury and PCBs in fish at upstream sites.

Evaluation of the effectiveness of three underwater reef fish monitoring methods in Fiji

Locally based and volunteer-based monitoring approaches have recently received greater attention as a cost-effective way to collect data on the environment and/or involve stakeholders in management. The present study compared three monitoring methods based on an underwater visual census (UVC) of reef fish in a customary area in Navakavu (Viti Levu Island, Fiji). Two non-scientific approaches involved (1) snorkellers from the village using vernacular names for five local focal fish taxa and (2) non-resident volunteers using the Reef Check target list of fish for the Indo-Pacific (nine focal taxa). These approaches were cross-checked with a comprehensive scientific survey (all fish recorded at the species level across 12 families). The three methods were compared in terms of accuracy, precision, and ability to highlight changes in fish abundance between the community-managed no-take zone (NTZ) and the fished area. We found that scientific and volunteer-based data were consistent in terms of means and variance of abundance estimates but that Reef Check focal taxa would not be suitable for monitoring the Navakavu marine area. On the contrary, the locally selected target taxa were appropriate but overestimates and imprecision were noticed in the fish counts made by the community members. Differences in abundance of two major target taxa (Lethrinidae and Mullidae) between the NTZ and the harvest area were not validated by the scientific observations. Calibration of community-based UVC is thus needed especially if information from the local biological monitoring program is used to guide management actions.

Seasonal variation in the composition of fish assemblages in small Amazonian forest streams: evidence for predictable changes

Summary1. The effects of seasonal inundation on the biology of fishes on floodplains of large Amazonian rivers are well studied. However, the small seasonal changes in headwater streams are generally considered to have little effect on fish assemblages.2. In this study, we analysed seasonal changes in the species composition and abundance of fish in small Amazonian forest streams. We sampled fish with hand and seine nets in headwater streams in a 10 000 ha terra‐firme forest reserve near Manaus, Brazil. Each stream was surveyed at the end of the 2005 dry season, at the beginning of the 2006 rainy season and at the beginning of the 2006 dry season, by means of a standardized sampling effort.3. The numbers of individuals and species caught were higher in the dry season, but rarefaction analyses indicated that greater species numbers could have been due simply to the larger number of individuals caught.4. Between the dry and rainy season, the direction of changes in species composition in multivariate space varied among sites, especially for quantitative (abundance) data. However, the observed variation among sites was the less than expected if the directions of change were random.5. Fish assemblages in the second dry season were more similar to those in the previous dry season than expected if changes in species composition among seasons were random. This indicates that a general seasonal pattern in fish assemblages can be detected, despite the existence of some erratic site‐specific changes.6. Most of the species that showed large seasonal variations in density occupy temporary ponds during the rainy season, when much of the valley is inundated and pond networks form adjacent to streams. Short‐duration lateral migrations to these ponds may play an important role in the seasonal fish‐assemblage dynamics in Amazonian headwater streams.7. Our results contrast with previous studies on small Amazonian streams, which have found little seasonal change in fish assemblages, and highlight the importance of the abundance of common species as an indicator of general fish assemblage structure in biological monitoring programmes.

A case report of elevated blood cadmium

A 45-year-old male paint technician was identified as having an elevated whole-blood cadmium of 5.9 microg/l (Occupational and Safety Health Administration reference range for workers: <or=5.0 microg/l) through a routine workplace biological monitoring programme. Other than smoking 1.5-2 packs of cigarettes daily for 23 years, no additional non-occupational exposures to cadmium were identified. Whole-blood cadmium results taken 5, 4 and 2 years earlier were 3.1, 4.0 and 4.3 microg/l, respectively. After reassignment to a position without cadmium exposure, his whole-blood cadmium level 7 weeks later was 6.1 microg/l. A careful exposure history revealed that he had recently changed the brand of cigarettes he smoked. When he switched back to his original brand and reduced his consumption to one pack per day, his cadmium level fell to 2.9 microg/l taken 12 weeks after the initial elevated result. Eight weeks after returning to his original position with cadmium exposure, the value was 3.4 microg/l. No elevation in urine cadmium was noted at any point. An analysis of the tobacco revealed that the cadmium content of the new brand was almost 1.5-fold greater than the original brand. These results suggest that the consumption of different brands of cigarettes can lead to marked variations in whole-blood cadmium levels.

Physical integrity: the missing link in biological monitoring and TMDLs

The Clean Water Act mandates that the chemical, physical, and biological integrity of our nation's waters be maintained and restored. Physical integrity has often been defined as physical habitat integrity, and as such, data collected during biological monitoring programs focus primarily on habitat quality. However, we argue that channel stability is a more appropriate measure of physical integrity and that channel stability is a foundational element of physical habitat integrity in low-gradient alluvial streams. We highlight assessment tools that could supplement stream assessments and the Total Maximum Daily Load stressor identification process: field surveys of bankfull cross-sections; longitudinal thalweg profiles; particle size distribution; and regionally calibrated, visual, stream stability assessments. Benefits of measuring channel stability include a more informed selection of reference or best attainable stream condition for an Index of Biotic Integrity, establishment of a baseline for monitoring changes in present and future condition, and indication of channel stability for investigations of chemical and biological impairments associated with sediment discontinuity and loss of habitat quality.

Effects of the Alqueva Dam Reservoir on the Distribution of Steppe Birds

The effects of the Alqueva Dam reservoir on the distribution of steppe birds (before and after flooding) was quantified using point-pattern analysis. Sampling points from the dam biological monitoring program, which included data from winter and breeding seasons, were used. To quantitatively assess spatial patterns, the point-pattern was tested using a sequence of statistical methods. Autocorrelation was measured using Ripley's L-function and O-ring, and was validated by a complete spatial randomness null model in the birds' suitable habitat. A gradient surface of probabilistic abundance was developed with a Kernel Density Estimator and compared with the Kappa Index of Agreement. The results indicate a decline in the absolute abundance of steppe birds in both seasons, but it is more evident in the breeding season. The results also show an increase in the mean distance between the point surveys, some evidence of a global trend toward the northeast, a decrease of patch values, and a disaggregation of continuous patches.

Diets of aquatic birds reflect changes in the Lake Huron ecosystem

Human activities have affected the Lake Huron ecosystem, in part, through alterations in the structure and function of its food webs. Insights into the nature of food web change and its ecological ramifications can be obtained through the monitoring of high trophic level predators such as aquatic birds. Often, food web change involves alterations in the relative abundance of constituent species and/or the introduction of new species (exotic invaders). Diet composition of aquatic birds is influenced, in part, by relative prey availability and therefore is a sensitive measure of food web structure. Using bird diet data to make inferences regarding food web change requires consistent measures of diet composition through time. This can be accomplished by measuring stable chemical and/or biochemical “ecological tracers” in archived avian samples. Such tracers provide insights into pathways of energy and nutrient transfer. In this study, we examine the utility of two groups of naturally-occurring intrinsic tracers (stable isotopes and fatty acids) to provide such information in a predatory seabird, the herring gull (Larus argentatus). Retrospective stable nitrogen and carbon isotope analysis of archived herring gull eggs identified declines in gull trophic position and shifts in food sources in Lake Huron over the last 25 years and changes in gull diet composition were inferred from egg fatty acid patterns. These independent groups of ecological tracers provided corroborating evidence of dietary change in this high trophic level predator. Gull dietary shifts were related to declines in prey fish abundance which suggests large-scale alterations to the Lake Huron ecosystem. Dietary shifts in herring gulls may be contributing to reductions in resources available for egg formation. Further research is required to evaluate how changes in resource availability may affect population sustainability in herring gulls and other waterbird species. Long-term biological monitoring programs are required to identify ecosystem change and evaluate its ecological significance.

Nanotechnology-based electrochemical sensors for biomonitoring chemical exposures.

The coupling of dosimetry measurements and modeling represents a promising strategy for deciphering the relationship between chemical exposure and disease outcome. To support the development and implementation of biological monitoring programs, quantitative technologies for measuring xenobiotic exposure are needed. The development of portable nanotechnology-based electrochemical (EC) sensors has the potential to meet the needs for low cost, rapid, high-throughput, and ultrasensitive detectors for biomonitoring an array of chemical markers. Highly selective EC sensors capable of pM sensitivity, high-throughput and low sample requirements (<50 microl) are discussed. These portable analytical systems have many advantages over currently available technologies, thus potentially representing the next generation of biomonitoring analyzers. This paper highlights research focused on the development of field-deployable analytical instruments based on EC detection. Background information and a general overview of EC detection methods and integrated use of nanomaterials in the development of these sensors are provided. New developments in EC sensors using various types of screen-printed electrodes, integrated nanomaterials, and immunoassays are presented. Recent applications of EC sensors for assessing exposure to pesticides or detecting biomarkers of disease are highlighted to demonstrate the ability to monitor chemical metabolites, enzyme activity, or protein biomarkers of disease. In addition, future considerations and opportunities for advancing the use of EC platforms for dosimetric studies are discussed.

USO DE MACROINVERTEBRADOS EM PROCEDIMENTOS DE BIOMONITORAMENTO EM ECOSSISTEMAS AQUÁTICOS

Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} The usual chemical procedures to analyse water samples yield information only concerning the water state on the moment of collection, thus short term contamination generally are left undetected. Moreover, this mode of analysis is not sensitive to physical alterations to habitats in aquatic ecosystems, since habitat evaluations do not depend on the simple chemical quality of local waters. This way, the integrity of the targeted ecosystem cannot be guessed from chemical and physical water quality. A more comprehensive evaluation of the health state of a given aquatic ecosystem can be obtained from the characterization of organisms that living therein. Currently, benthic macroinvertebrates (usually aquatic insects) are widely used in evaluations of ecological water quality in association with biological monitoring tools. In the present revision, we presented some traits of macroinvertebrates and how macroinvertebrate communities are used as bioindicators in association with biological monitoring tools. We focused on four methodologies, being three of which widely used in many countries in national, regional or local biological monitoring programs: Biotic Index, Predictive Models, Multimetrics Index, and a fourth methodology still under construction with great potential of application named Biological and Ecological Traits.

A normative study of levels of uranium in the urine of British Forces personnel

Objectives: The UK Ministry of Defence (MoD) controls a biological monitoring programme that includes testing for uranium in personnel who served in the conflict in Iraq in 2003. To help...

Biological Monitoring in the Amazon: Recent Progress and Future Needs

RESUMENO monitoramento biológico é uma ferramenta fundamental para o manejo ambiental. Ele permite avaliar o estado do ambiente ao longo do tempo, informando sobre a necessidade e sobre as conseqüências das medidas de manejo. Na Amazônia, o monitoramento é uma atividade particularmente difícil devido à variedade das ameaças ambientais, à vastidão da área, e à enorme riqueza de espécies. Para ser eficiente, um programa de monitoramento precisa ser claramente enraizado em uma ameaça ambiental que se pretende resolver – só assim haverá um critério claro para decidir quais variáveis serão medidas e como planejar essa medição. Numa área tão grande quanto a Amazônia, é particularmente importante que os programas de monitoramento definam a priori a sua escala de atuação. Um desenho amostral que serve para a escala local será deficiente na escala regional, e vice‐versa. A idéia de trabalhar simultaneamente em diferentes escalas espaciais é louvável mas altamente arriscada. Finalmente, quando o monitoramento requer identificação de espécies, a riqueza biológica da Amazônia e a escassez de pessoal qualificado limitam o avanço do trabalho. Para garantir a viabilidade futura das atividades de monitoramento é essencial investir com criatividade e determinação no treinamento de observadores. Este comentário sublinha alguns aspetos de progresso recente em monitoramento biológico da Amazônia e identifica três necessidades para o futuro: 1) Garantir a orientação do monitoramento para ameaças claramente identificadas; 2) Trabalhar em uma escala espacial prioritária, definida antes do lançamento do programa; e 3) Investir no treinamento de observadores.El monitoreo biológico es una herramienta fundamental para la gestión ambiental porque permite evaluar el estado del ambiente al largo del tiempo, informando sobre la necesidad e sobre las consecuencias de acciones de gestión. En Amazonia, el monitoreo es una actividad particularmente difícil gracias à la variedad de amenazas, a la extensión de la área, y a la enorme riqueza de especies. Para ser eficiente, un programa de monitoreo necesita ser claramente enraizado en una amenaza ambiental que se pretende resolver – solo así existirá un criterio claro para decidir lo que medir y como medirlo. En una área tan grande como Amazonia, se hace esencial que los programas de monitoreo establezcan a priori su escala de actuación. Un diseño de muestreo que funciona en la escala local será deficiente en la escala regional y vice‐versa. La idea de trabajar simultáneamente en distintas escalas espaciales es muy arriesgada – hay que priorizar. Finalmente, cuando el monitoreo exige identificación de especies, la riqueza de Amazonia y la escasez de personal calificado limitan el progreso del trabajo. Para garantizar la viabilidad del monitoreo, se hace esencial invertir con creatividad y determinación en el entrenamiento de observadores. Este comentario refiere algunos progresos recientes en el monitoreo biológico de Amazonia y identifica tres necesidades para el futuro: 1) Garantizar que cada programa esté claramente orientado para una amenaza ambiental; 2) Trabajar en una escala espacial prioritária; y 3) Invertir en el entrenamiento de observadores.

Electrochemical Sensors for the Detection of Lead and Other Toxic Heavy Metals: The Next Generation of Personal Exposure Biomonitors

To support the development and implementation of biological monitoring programs, we need quantitative technologies for measuring xenobiotic exposure. Microanalytical based sensors that work with complex biomatrices such as blood, urine, or saliva are being developed and validated and will improve our ability to make definitive associations between chemical exposures and disease. Among toxic metals, lead continues to be one of the most problematic. Despite considerable efforts to identify and eliminate Pb exposure sources, this metal remains a significant health concern, particularly for young children. Ongoing research focuses on the development of portable metal analyzers that have many advantages over current available technologies, thus potentially representing the next generation of toxic metal analyzers. In this article, we highlight the development and validation of two classes of metal analyzers for the voltammetric detection of Pb, including: a) an analyzer based on flow injection analysis and anodic stripping voltammetry at a mercury-film electrode, and b) Hg-free metal analyzers employing adsorptive stripping voltammetry and novel nanostructure materials that include the self-assembled monolayers on mesoporous supports and carbon nanotubes. These sensors have been optimized to detect Pb in urine, blood, and saliva as accurately as the state-of-the-art inductively coupled plasma-mass spectrometry with high reproducibility, and sensitivity allows. These improved and portable analytical sensor platforms will facilitate our ability to conduct biological monitoring programs to understand the relationship between chemical exposure assessment and disease outcomes.

Seasonal Patterns and Abundance of Copepods in Kentucky Lake, USA

The distributions and abundance of free-living copepods in Kentucky Lake were examined for the years 2000, 2002, and 2004. Vertical tow samples were collected from 16 sites every 16 days for April through November and every 32 days for December through March as part of a long-term physicochemical and biological monitoring program. Copepods comprised 14.39% of the zooplankton in tow net samples, but only 6 species were abundant. Ectocyclops phaleratus, Cryptocyclops bicolor, Mesocyclops tenuis, Eurytemora affinis, Leptodiaptomus siciloides, and Acanthocyclops vernalis accounted for 86.44% of adult copepods. With the exception of E. affinis that was found throughout the year, observed seasonal density maxima occurred at differing points during the year for each of the other major species. Most species were present during spring and summer and absent or found in low numbers throughout the remainder of the year. A. vernalis, M. tenuis, and C. bicolor exhibited density decreases that corresponded with day 160. Day 160 also marked rapid declines of other common zooplankton such as Bosmina sp., Daphnia retrocurva, and Diaphanosoma sp. Similarities in annual distribution patterns among all zooplankton suggest that common factors are exerting influence on abundances and seasonal distributions.

Hurricane impacts on coastal ecosystems

Hurricanes, typhoons, and other cyclonic disturbances often produce sudden, massive disturbances in estuaries and other coastal ecosystems around the world. Compared with other ecological disturbances, such as prairie and forest fires, tree falls, and coral bleaching events, the effects of hurricanes are usually studied in isolation of each other and rarely as repeated or even ecologically predictable events across an area of sustained hurricane activity. Studies of their effects have rarely contributed to the growing body of theory on ecological disturbance and ecosystem resiliency and they are conspicuously absent from ecological textbooks. Since 1996, there has been an increase in the frequency of hurricane landfalls in the southeastern United States that is predicted to continue for some years into the future (Goldenberg et al. 2001; Emanuel 2005; Webster et al. 2005). Coupled with the availability of results from many water quality and biological monitoring programs now in place in these coastal systems, the increase in hurricane activity now provides an opportunity to begin the systematic investigation of how a series of hurricanes might produce cumulative and perhaps even irreversible effects on coastal ecosystems. One particular example that is highlighted in this special issue of Estuaries and Coasts is the occurrence of four major hurricanes to make landfall in Florida in a two-month period of 2004. In some localities, sequential hurricanes made landfall in close proximity to each other, while in other regions of coastal Florida, the repeated heavy rains associated with the multiple hurricanes had effects that were distinct from the wind and storm surge effects often associated with hurricanes.

Line‐intercept laboratory subsampling estimates periphyton biovolumes more efficiently than standard methods

Summary Algal assemblages have been included in biological monitoring in a number of national, large‐scale and long‐term biological monitoring and assessment programmes of streams, lakes and wetlands. However, there has been no substantial investigation of alternative enumeration strategies. We compared the sampling efficiency of the common periphyton subsampling strategies of counting 300 cells by strip counts or random fields and measuring 10 cells per taxon for biovolume, with line‐intercept sampling (LIS), using samples collected from four streams differing in canopy cover and discharge. We also simulated the optimum ratio of cells tallied to cells measured for biovolume for all approaches. LIS was 1·6–5·5 times more efficient at estimating algal taxa biovolume than the 300‐cell count methods. LIS performed best relative to conventional 300‐cell count methods in streams with high biovolume, although efficiency gains were still noticeable in low biovolume streams. In addition, LIS tended to detect more taxa than the conventional 300‐cell target biological assessment methods. In simulations, LIS was more efficient than the conventional methods for nearly all combinations of target cell count and cells measured for biovolume. No single optimal ratio of cells counted to cells measured was found. The target cell count that resulted in the greatest efficiency was higher in assemblages with large variation in cell density. Likewise, assemblages with high variance in taxa biovolume were most efficiently sampled by measuring more cells. Synthesis and applications. An increase in sampling efficiency as a result of greater adoption of LIS sampling may result in more accurate estimation of the relationships between periphyton community composition and environmental factors, and more sensitive detection of impacts using stream periphyton. Additionally, LIS may improve estimates in other ecological research fields employing microscopic counting chambers.

Coplanar and non-coplanar congener-specificity of PCB bioaccumulation and immunotoxicity in sea stars

The sea star Asterias rubens (L.), a representative species of the North Sea benthic environment, was exposed to a mixture of 10 selected PCB congeners (3 coplanar or c-PCBs, and 7 non-coplanar) via experimentally contaminated sediments. Both the degree of bioaccumulation and subsequent immunotoxic effects of these PCBs were determined. A strong congener-specificity for both bioaccumulation and immunotoxicity was found as well as a probable induction of a congener-specific detoxification mechanism resulting in the dramatic decrease in body levels of the three coplanar congeners tested (PCBs 77, 126 and 169). Moreover, a correlation was found between the bioaccumulation of c-PCBs and their immunotoxic effects. These findings suggest that coplanar congeners should be included in the list of congeners recommended to be analyzed for biological impact-oriented marine monitoring programmes.

Community Response Patterns: Evaluating Benthic Invertebrate Composition In Metal-Polluted Streams

Human activities are modifying the condition and character of ecosystems at a rapid rate. Because of these rapid changes, questions concerning how ecosystems and their assemblages respond to anthropogenic stressors have been of general interest. Accurate prediction of assemblage composition in ecosystems with anthropogenic degradation requires that we assess both how assemblages respond to stressors and the generality of the responses. We ask whether assemblage composition among stream sites becomes more similar after exposure to a common stressor. Using data from biological monitoring programs in the southern Rocky Mountain ecoregion of Colorado and in West Virginia, we compare benthic invertebrate similarity and assemblage composition among sites having different levels (background, low, medium, and high) of heavy-metal pollution. Invertebrate assemblages were most similar within the background metal category, and similarity was progressively lower in low, medium, and high metal categories. An analysis of the frequency of occurrence of genera within metal categories reveals taxonomic shifts that conform to expectations based on metal tolerance of benthic invertebrates. However, different metal-tolerant genera were found at different metal-impacted sites, suggesting that local abiotic and biotic processes may influence the identity of the metal-tolerant genera that become established in polluted sites. Low community similarity in the medium and high-metal categories suggests that accurate prediction of assemblage composition at impacted sites may be challenging.

Evolving policies for conservation: An Historical Profile of the Protected Area System of Nepal

Nepal has instituted progressive conservation programmes since the 1970s. This move was in reaction to very rapid rates of land clearance in the lowland areas of the country and an opening up to the world that led to nature-based tourism as a major economic enterprise. Formal conservation began with the passage of national legislation in 1973 offering strong protection for national parks and wildlife reserves, but denied usufruct rights to rural communities. From the late 1970s to the 1990s, the legislation was amended several times. Each case was, in several fundamental ways, a loosening of control by government authorities. Nepal now has buffer zone legislation and allows for the designation of conservation areas in addition to the more-strictly defined categories. Beginning in the 1990s, both government and foreign-backed projects have been implementing landscape level conservation approaches; a number of initiatives in trans-boundary protected area management with India and China have also begun and non-governmental organizations have taken an increasingly active role. This paper considers the expansion of the protected areas network in light of historical, cultural and economic factors and concludes that Nepal has been reactive in adopting conservation programmes. Both outside and inside influences have strongly affected the development of conservation programmes and there are several areas in which more work needs to be done. This includes the need for implementing both national and international conservation law and adopting social and biological monitoring programmes in and around protected areas. In addition, factors outside the control of conservation officials (i.e. a Maoist insurgency) have indirectly hindered conservation programmes in recent years and have greatly complicated prospects for further success.

Application of epiphytic diatoms in water quality monitoring of Lake Velence - recommendations and assignments

The suitability of benthic diatoms in the biological monitoring program of the water quality of Lake Velence was tested. Diatom indices were calculated with the aid of the software Omnidia based on reed periphyton samples collected between 1988 and 1990, and 1999 to 2004. We have pointed out which indices are appropriate for indicating the water quality changes of Lake Velence. The correlation between the indices IBD, IPS, IDG, and the total nitrogen, total phosphorus content of the water and chlorophyll-a content of the periphyton was calculated. Significant negative correlation was found between the indices and the total phosphorus content of the water. Moreover, we concluded that the chlorophyll-a content of the periphyton related to surface area can also provide information about the water quality. Based on these results the index IBD seems to be the most suitable for the water quality analysis of Lake Velence. Recommendations are provided here concerning the ecological status classification of Lake Velence based on epiphytic diatoms; unaccounted questions and future assignments are also outlined in connection with this.

Delaware Bay salt marsh restoration: Mitigation for a power plant cooling water system in New Jersey, USA

In 1994 Public Service Electric and Gas of New Jersey (PSE&G), now Public Service Enterprise Group (PSEG), proposed and implemented a program to offset egg, larvae and fish losses at the cooling water intake at Salem Generating Station. The program included wetland habitat restoration, fish ladder installation, new cooling water intake technology, and a biological monitoring program. The wetland habitat restoration was the core component and the most controversial aspect of the program. It addressed two types of habitats: diked salt hay farms and wetlands dominated by Phragmites australis. The wetland restoration program used ecological engineering principles to restore approximately 4550 ha. It also protected upland buffers and other lands for a total of over 8700 ha. Eight fish ladders were installed to allow anadromous river herring to return to previously blocked spawning habitat. PSEG also implemented operational changes, installed advanced cooling water intake technology to reduce losses of invertebrates and early life stages of fish, and conducted studies of behavioral deterrents. The biological monitoring program continues to assess the abundance and distribution of juvenile coastal migratory fish species while they are in the Delaware River Estuary; it also monitors use of wetlands by fish and invertebrates.