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There can be few indoor workplaces that are more subject to the meteorological and atmospheric conditions of their locations than permanent stations on the high, inland polar plateau of Antarctica. The US Amundsen-Scott South Pole Station is such a workplace, totally isolated during the 8–9 months of the austral winter, more than 800 miles (1287 km) from the nearest other human habitation. The wintering party at the South Pole must deal with all the demands and stressors of an isolated, confined, and extreme environment without the prospect of relief from the outside world. In 1975, the seventeen men chosen to winter at the South Pole had an additional challenge. In February, as the austral winter was about to begin, a new geodesic-domed research station had just been completed. The station was the first of its kind, and the vagaries of its design and construction would be significant factors in the health and well-being of station residents as winter progressed. Potential physical and psychological problems from isolation literature are commented upon, and some significant events from this noteworthy winter are described. In addition, supporting quantitative data from current research at South Pole are used to better understand these events.

Energy dissipation and fragmentation of rock is of interest for mine-to-mill operations in order to understand breakage and to minimize energy consumption during blasting at the mine site, and comminution at the processing plant. In this regard, high velocity impact breakage of long granite cores, called bars, has been studied with instrumented strain gages to follow the energy dissipation gradient along the bar length resulting from the strain waves generated by impact. As a result of high velocity impact, three zones have been identified (fragmentation, fracture, and elastic) and these three zones have been characterized in 3D using X-ray tomography. The fragmentation zones of the granite bars were studied in detail to describe the particle size distribution and the particle shape characteristics. Finally, the experimental energy dissipation for the fragmentation zone was found to be in close agreement with the expected energy calculated from the Bond work equation, if the anisotropic granite particles are defined by length rather than by sieve size.

One goal of ecosystem-based management is studying an ecosystem and its people, the socio-ecological system, in a qualitative and quantitative modeling approach that can provide management agencies with possible outcomes of their actions using scenario forecasting. Ecosystem-based fisheries management strives to use the socio-ecological system approach, including direct and indirect impacts on multiple species including the behavioral responses of fishers after a regulatory change (a gillnet ban). Here, we link fisher behavioral networks with a mass-balanced food-web ECOPATH network model of an estuarine ecosystem and its commercial fisheries for an analysis of fishing impacts after a gillnet ban on multiple species using ECOSIM. We modeled fisher behavioral networks using reported catches of species from individual fishers along with the gear fished to create nodes in a gear/species affiliation network. Individual fishers with common gear/species use are indicative of common fishing behavior. When such fishers have high network centrality and are engaged in multiple gear/species fisheries, they can transition to other gear/species fisheries along “switching pathways” when facing a regulatory change. We used an index of joint gear participation to identify likely gear switching pathways, and we predicted changes in fishing effort after a gill net ban. We simulated the gill net ban in ECOSIM under two scenarios of fishing effort: Scenario 1, gill net fishing effort of 0%; Scenario 2, gill net fishing effort of 0% with increased effort in the alternative gear fisheries using the predicted switching pathways for the affiliation network. Scenario 1 predicted an increase in flounder (Paralichthys spp.) biomass over a decade. Under Scenario 2, fishers targeting flounders were predicted to switch from gill nets to pound nets. Scenario 2 predicted a 7% decline in flounder biomass over ten years, rather than an increase in flounders. The gillnet ban with increased effort due to switching is predicted to have the opposite effect on the conservation goal, which was to increase flounder stocks. Fishery management that incorporates a socio-ecological approach modeling both fisher behaviors and multi-species ecosystem responses can reveal single-species responses that are in the opposite direction of the anticipated management goals.

This article offers a way to measure agreement in participatory mapping. We asked subject matter experts (SMEs) to draw where Sudanese ethnic groups were located on a map. We then used an eigenanalysis approach to determine whether SMEs agreed on the location of ethnic groups. We used minimum residual factor analysis to assess the extent of interinformant agreement among SMEs’ judgments of four ethnic groups’ spatial locations. Although we found little evidence of the lumper/splitter problem, some SMEs drew larger polygons than others, and we provide directions on how to reduce this potential bias. Finally, the results of the geospatial agreement analysis were validated through a comparison of other sources of geospatial data for three of the four ethnic groups.

Sample size determination for open-ended questions or qualitative interviews relies primarily on custom and finding the point where little new information is obtained (thematic saturation). Here, we propose and test a refined definition of saturation as obtaining the most salient items in a set of qualitative interviews (where items can be material things or concepts, depending on the topic of study) rather than attempting to obtain all the items. Salient items have higher prevalence and are more culturally important. To do this, we explore saturation, salience, sample size, and domain size in 28 sets of interviews in which respondents were asked to list all the things they could think of in one of 18 topical domains. The domains-like kinds of fruits (highly bounded) and things that mothers do (unbounded)-varied greatly in size. The datasets comprise 20-99 interviews each (1,147 total interviews). When saturation was defined as the point where less than one new item per person would be expected, the median sample size for reaching saturation was 75 (range = 15-194). Thematic saturation was, as expected, related to domain size. It was also related to the amount of information contributed by each respondent but, unexpectedly, was reached more quickly when respondents contributed less information. In contrast, a greater amount of information per person increased the retrieval of salient items. Even small samples (n = 10) produced 95% of the most salient ideas with exhaustive listing, but only 53% of those items were captured with limited responses per person (three). For most domains, item salience appeared to be a more useful concept for thinking about sample size adequacy than finding the point of thematic saturation. Thus, we advance the concept of saturation in salience and emphasize probing to increase the amount of information collected per respondent to increase sample efficiency.

We used stable isotope ratios of nitrogen ( 15 N/ 14 N) as a validation tool for determining the accuracy of the effective trophic levels computed in network analysis models for Core Sound, North Carolina, USA. Ecological network models (using Ecopath) were assembled for two trawling management areas, closed areas where shrimp trawling has been restricted for 30 years, and open trawling areas within the estuary. Effective trophic levels (ETLs) were computed from the two Ecopath models and compared with δ 15 N values measured from the same species at the same time in the two areas. Comparisons of ETLs between species compartments of the two models were very similar, and ETLs were positively related to δ 15 N values. Linear regression of ETL as a predictor of δ 15 N value was highly significant ( R 2 = 0.50, p > 0.00001), suggesting that δ 15 N values increase by 2.52‰ per trophic level. This increase in δ 15 N value agrees well with a recent global meta-analysis of nitrogen fractionation estimates. There was no significant difference in δ 15 N values between trawling zones over all species examined, although there were significantly higher δ 15 N values in the areas open to trawling for certain species of fish (pinfish, spot) and invertebrate (blue crabs). Atlantic menhaden, which feed on detritus and zooplankton, had much higher δ 15 N values than the Ecopath ETL and δ 15 N regression model predicted (large studentized residuals), suggesting that Ecopath incorrectly computes the trophic level of animals that consume dead material (in our model, detritus and shrimp trawl bycatch species). Shrimp trawl bycatch species are mostly pinfish, spot and blue crabs, with ETLs of 2.5 or higher, but are inappropriately assumed to be at trophic level 1 when dead in Ecopath. Despite this discrepancy for some species of detritivores and scavengers, we conclude that this Ecopath network model of Core Sound is reliable and predicts with good accuracy the shifts and changes in trophic level and diet as measured by stable isotopes and observed in diet studies. The Core Sound network model will be a useful approach when predicting impacts in the ecosystem due to changes in trawling or other fisheries management decisions.

Today researchers need an efficient and valid approach to mine and analyze the large amount of textual information that is available. Automated coding approaches offer promise but a major concern is the accuracy of such codes in capturing the meaning and intent of the original texts. We compare the recall (number of codes identified) and precision (accuracy of the codes) that included bodies of texts coded (1) manually by humans based on the Outline of Cultural Materials (OCM) code book, (2) semi-automatically by computers that used a human-generated content dictionary containing Rapid Ethnographic Retrieval (RER) codes, and (3) automatically by computers that used an automated version of the OCM content dictionary (AOCM). We applied network visualization and statistics to quantify the relative importance of codes. The semi-automatic coding approach had the highest balance of recall and precision. Network visualization and metrics identified relationships among concepts and frame codes within a context. Semi-automated approaches can code much more data in a shorter period of time than humans and researchers can more easily refine content dictionaries and analyses to address errors, which makes semi-automated coding a promising method to analyze the ever-expanding amount of textual information that is available today.

The management of the spiny dogfish (Squalus acanthias) is a matter of international concern, as this species was a candidate for inclusion in lists for trade regulation. The major demand for its meat is from the European Union (EU) market, with the US and Canada as its two major contributors. The US has yet to support a spiny dogfish listing, although the US Atlantic stock is under a fishery management plan (FMP) that proved to be successful in providing a certified sustainable fishery. We employed a cumulative sum technique to compare trade data for frozen spiny dogfish export from US and Canada to the EU in relation to the FMP adoption. We also constructed a social network to visualize changes in the European trade scenario for spiny dogfish after adoption of the FMP and to predict future trade flow potentially affecting the conservation status of regional dogfish stocks in relation to recent management measures introduced in Europe. The social network analysis revealed that the exclusion of spiny dogfish from trade regulation lists eventually will affect the conservation status of dogfish stocks in Africa, Asia, South America, and the Mediterranean and Black Seas. Our results suggest that the species listing would provide an economic benefit for the US Northwest Atlantic fishery, and will eventually foster the conservation status of other regional stocks worldwide and the search for a more sustainable global exploitation of spiny dogfish.

We report on a rapid and practical method to assess social dimensions of performance in small-scale and industrial fisheries globally (Social Wellbeing in Fisheries Tool (SWIFT)). SWIFT incorporates aspects of security (fairness and stability of earnings, benefits of employment to local fishing communities, worker protection, and personal safety and health in communities associated with fisheries); flexibility (including opportunity for economic advancement); and the fishery’s social viability (including whether the fishery is recruiting new harvesters and diverse age classes of workers, whether women’s participation and leadership in global production networks are on an upward trajectory.). We build on resilience research by conceptualizing wellbeing in terms of security, flexibility, and viability, and assessing wellbeing at individual, community, and system levels. SWIFT makes social performance measures more broadly accessible to global production networks, incorporates an everyday understanding of wellbeing for people involved in the seafood industry, and helps put social sustainability into measurable terms that are relevant for businesses.

We show how land-use change can affect fisher-harvesting behavior. We test whether fisher harvesting behavior can be predicted by landscape change patterns at local (~ 200 km) and regional (~ 1200 km) levels. Our data suggest that fishers harvesting in areas near tree plantations reduced benthic-invertebrate harvests in favor of demersal and pelagic finfish that are usually located further offshore. Fishers' management areas, which were near tree plantations, had higher chlorophyll-a values, and contained shellfish with more endobionts. Technology (owning a boat) and experience (age, years fishing, and alternative livelihoods) explained little in fisher-harvesting behavior. The flagship Chilean fisheries management program and seafood companies sourcing from these areas will need to respond to these new challenges. Despite complexities in designing cross-scale, social-ecological studies, we can no longer ignore the interconnectedness of commodities in the biosphere.

The US Long Term Ecological Research (LTER) program began in 1980 with the mission of addressing long-term ecological phenomena through research at individual sites, as well as comparative and synthetic activities among sites. We applied network science measures to assess how the LTER program has achieved its mission using intersite publications as the measure of collaboration. As it grew, the LTER program evolved from (a) a collection of independent sites (1981–1984) to (b) multiple ephemerally connected groupings with a gradual increase in collaboration (1985 to about 1998) to (c) a largely collaborative, densely connected network (from approximately 1999 on). Some sites demonstrated “preferential attachment” by contributing more to the evolution of network cohesion than others. Collaborative efforts of LTER scientists included cross-site measurements and comparions, information technology transfer, documentation of methodologies, and synthesis of ecological concepts. Network science provides insights t...

Population growth in U.S. coastal areas has spawned conflicts due to increasing competition between commercial and leisure uses of coastal resources. Organizations representing different user groups routinely misrepresent the causes and severity of environmental stresses to further their political and economic agendas, often predicting extinctions of fish and shellfish and undermining balanced and reasoned management alternatives. This article illustrates this phenomenon with data on conflicts stemming from perceived problems concerning marine resources involving recreational and commercial fishers, with additional attention to managers' roles in such disputes. Cultural consensus analysis is used to understand variation in cultural conceptions concerning coastal resource problems among the different groups. Finally, the method's application for resolving environmental conflicts is discussed.

Participant observation approaches have been important components of ethnographic research. Generally, however, observation has been emphasized over participation. But there are many ethnographic contexts in which active participation by the ethnographer is advantageous, if not essential, to the collection of quality data. This article provides a framework for analyzing the potential benefits of an ethnographer participating in an active role in a given ethnographic setting. Using theories from organizational studies and the organization of work, a framework for determining the attributes relevant to a given active role for the collection of ethnographic data is presented. Three case studies are analyzed using such a framework. They include an ethnographic study of a fish camp in Alaska; a study of the red-light district in Washington, D.C.; and a study of Chinese and Taiwanese immigrant communities in Southern California.

Monoclonal antibodies have begun to show great clinical promise for the treatment of cancer. Antibodies that can directly affect a tumor cell's growth and/or survival are of particular interest for immunotherapy. Previously, we described monoclonal antibody DMF10.62.3 that had antiproliferative and proapoptotic effects when it bound an antigen of unknown identity on tumor cells in vitro. In this report, we determined that DMF10.62.3 and a clonally related antibody DMF10.167.4 recognize the ganglioside GM2. These antibodies react with a GM2 epitope that is expressed on a large number of tumor cell lines, including human melanoma and small cell lung carcinoma, but not on normal primary lines or most normal tissues. Interestingly, this pattern of cellular reactivity is distinct from that reported for other previously described GM2 antibodies, a difference that is presumably due to DMF10.167.4's binding to a unique GM2-associated epitope. Additional characterization of DMF10.167.4 revealed that this antibody was able to induce apoptosis and/or block cellular proliferation when cultured in vitro with the human Jurkat T lymphoma, CHL-1 melanoma, and SBC-3 small cell lung carcinoma lines. In vivo, DMF10.167.4 antibody was well tolerated in mice and did not detectably bind to or damage normal tissues. However, this antibody was able to prevent murine E710.2.3 lymphoma, human CHL-1 melanoma, and SBC-3 small cell lung carcinoma lines from establishing tumors in vivo and blocked progression of established CHL-1 and SBC-3 tumors in vivo. Therefore, monoclonal antibody DMF10.167.4 has immunotherapeutic potential.

The influence of isolation and confinement on social support and depressed mood was examined in a study of 235 men and women who spent a year at McMurdo Station in Antarctica, and a study of 77 men and women who spent a year at the Amundson–Scott South Pole Station. Although availability of support remained unchanged, there was a significant decrease in reported satisfaction with support obtained, as well as a significant increase in depressed mood. Satisfaction with support was inversely associated with depressed mood at the beginning and end of isolation and confinement. At the end of winter, this association varied by source of support. High levels of tension-anxiety, depression and anger preceded an increase in advice seeking, but high levels of advice seeking also preceded an increase in tension-anxiety and depression. Results suggest a significant erosion of social support under conditions of prolonged isolation and confinement, leading to an increase in depressed mood.

In recent years a consensus has emerged from molecular phylogenetic investigations favoring a common endosymbiotic ancestor for all chloroplasts. It is within this conceptual framework that most comparative analyses of eukaryotic biochemistry and genetics now are interpreted. One of the first and most influential sources of data leading to this consensus is the remarkable similarity in genome content among all major plastid lineages. Here we report statistical analyses of two sequence data sets, genes encoding ribosomal proteins and transfer RNAs, from representatives of the three primary plastid lineages and a mitochondrion. The latter almost certainly originated in an independent endosymbiotic association and serves as a control for similarity due to convergent evolution. When genes related to organelle-specific function are factored out, plastid genomes appear to be no more similar to each other than they are to the mitochondrion. Total similarities in gene content, measured as deviations from the expectation from a process of random gene loss, are correlated with the extent of reduction in the two genomes compared. They do not appear to reflect putative evolutionary relationships among plastids. These analyses indicate that similarities in plastid genome content are better explained by convergent evolution due to constraint on gene loss than by a shared evolutionary history. A review of other data cited as support for a single plastid origin suggests that the alternative hypothesis of multiple origins is at least equally consistent in most cases.

We present a graph theoretic model of analysing food web structure called regular equivalence. Regular equivalence is a method for partitioning the species in a food web into ‘‘isotrophic classes’’ that play the same structural roles, even if they are not directly consuming the same prey or if they do not share the same predators. We contrast regular equivalence models, in which two species are members of the same trophic group if they have trophic links to the same set of other trophic groups, with structural equivalence models, in which species are equivalent if they are connected to the exact same other species. Here, the regular equivalence approach is applied to two published food webs: (1) a topological web (Malaysian pitcher plant insect food web) and (2) a carbon-flow web (St. Marks, Florida seagrass ecosystemfood web). Regular equivalence produced a m ore satisfactory set of classes than did the structural approach, grouping basal taxa with other basal taxa and not with top predators. Regular equivalence models provide a way to mathematically formalize trophic position, trophic group and trophic niche. These models are part of a family of models that includes structural models used extensively by ecologists now. Regular equivalence models uncover similarities in trophic roles at a higher level of organization than do the structural models. The approach outlined is useful for measuring the trophic roles of species in food web models, measuring similarity in trophic relations of two or more species, comparing food webs over time and across geographic regions, and aggregating taxa into trophic groups that reduce the complexity of ecosystem feeding relations without obscuring network relationships. In addition, we hope the approach will prove useful in predicting the outcome of predator–prey interactions in experimental studies. r 2003 Elsevier Science Ltd. All rights reserved.

We established trophic guilds of macroinvertebrate and fish taxa using correspondence analysis and a hierarchical clustering strategy for a seagrass food web in winter in the northeastern Gulf of Mexico. To create the diet matrix, we characterized the trophic linkages of macroinvertebrate and fish taxa present inHalodule wrightii seagrass habitat areas within the St. Marks National Wildlife Refuge (Florida) using binary data, combining dietary links obtained from relevant literature for macroinvertebrates with stomach analysis of common fishes collected during January and February of 1994. Heirarchical average-linkage cluster analysis of the 73 taxa of fishes and macroinvertebrates in the diet matrix yielded 14 clusters with diet similarity ≥ 0.60. We then used correspondence analysis with three factors to jointly plot the coordinates of the consumers (identified by cluster membership) and of the 33 food sources. Correspondence analysis served as a visualization tool for assigning each taxon to one of eight trophic guilds: herbivores, detritivores, suspension feeders, omnivores, molluscivores, meiobenthos consumers, macrobenthos consumers and piscivores. These trophic groups, corss-classified with major taxonomic groups, were further used to develop consumer compartments in a network analysis model of carbon flow in this seagrass ecosystem. The method presented here should greatly improve the development of future network models of food webs by providing an objective procedure for aggregating trophic groups.

Recent studies have found that individuals tend to see themselves as more central in a network than they really are. This body of work has generally been done among small groups of

Middle ear infection, also known as otitis media (OM), is a major public health problem among American children. Although clinical and epidemiological aspects of OM have been intensely studied, cultural factors that may be contributing to the problem of OM have received less attention. This article presents findings from an ethnographic study exploring beliefs about OM and responses to the illness among parents from eastern North Carolina. In-depth interviews were conducted with a convenience sample of nine mothers in order to learn more about parents' explanatory models of OM, the source of their beliefs, and how they respond to the illness. A survey instrument based on their statements was then constructed and administered to a convenience sample of 79 parents. The survey consisted of belief statements about OM, as well as questions pertaining to sources of beliefs, the home management of the disease, and the effects of the illness on families. A cultural consensus analysis of responses to belief statements indicates that parents shared a common model of OM. Beliefs about risks, symptoms, and causes of OM were similar to the current biomedical model of the illness, but their divergent beliefs about the diagnosis, prognosis and treatment of OM could lead to unnecessary use of health care services. Clinicians, family, and friends were reported to be important sources of information about OM. Parents also reported using similar home management strategies and care seeking behaviors to minimize the impact of the illness on their children and families. While these findings need to be replicated in studies with larger, more representative samples, this study suggest that ethnographic approaches may provide new insights into the cultural dimension of the problem of OM.

Humans who interact directly with local ecosystems possess traditional ecological knowledge that enables them to detect and predict ecosystem changes. Humans who use scientific ecological methods can use species such as mollusks that lay down annual growth rings to detect past environmental variation and use statistical models to make predictions about future change. We used traditional ecological knowledge shared by local Iñupiaq, combined with growth histories of two species of mollusks, at different trophic levels, to study local change in the coastal ecosystems of Kotzebue, Alaska, an area in the Arctic without continuous scientific monitoring. For the mollusks, a combination of the Arctic Oscillation and total Arctic ice coverage, and summer air temperature and summer precipitation explained 79–80% of the interannual variability in growth of the suspension feeding Greenland cockle (Serripes groenlandicus) and the predatory whelk (Neptunea hero), respectively, indicating these mollusks seem to be impacted by local and regional environmental parameters, and should be good biomonitors for change in coastal Alaska. The change experts within the Kotzebue community were the elders and the fishers, and they observed changes in species abundance and behaviors, including benthic species, and infer that a fundamental change in the climate has taken place within the area. We conclude combining traditional and scientific ecological knowledge provides greater insight than either approach alone, and offers a powerful way to document change in an area that otherwise lacks widespread quantitative monitoring. This work was funded by a grant from the US National Science Foundation (NSF) Office of Polar Programs (OPP-0222423) to William G. Ambrose Jr., Lisa M. Clough, David C. Griffith and Jeffrey C. Johnson, the Norwegian Research Council to Michael L. Carroll, the BBVA Foundation and Spanish Ministry of Education and Competitiveness grant MTM2012-37195 to Michael Greenacre, and with funds from the Howard Hughes Medical Institute through Bates College.

Earlier research has shown a relationship between various forms of structural centrality and perceived leadership and role satisfaction in small experimental groups. The limited amount of research on this topic in naturally occurring social networks has yielded results that often conflict with one another. Different results have generally been attributed to possible differences in task environments. This paper examines the relationship between two types of structural centrality and perceived influence, role satisfaction, and perceived effectiveness in an environmental resource management program. Findings in this paper suggest that the observed differences in relationships between the network and other variables is partly a function of global network properties (e.g., marginality of subgroups) and related task environments.

Behavioral observations and sociometric ratings were assessed in separate 3- and 4-year-old child care classes across a two year period. A cross sequential design included three cohorts. Cohort A was observed at age 4, Cohort B at ages 3 and 4 and Cohort C was observed at age 3 yielding two separate cross sectional comparisons and a longitudinal comparison across ages 3 and 4. Social network analyses were used to determine the relation between behavioral measures of social interactions and sociometric ratings, developmental changes in the degree of organization of the social networks in each class, and the degree to which gender was an organizing principle in the social structure of both age groups. In general, correspondence between the behavioral observations and sociometric ratings increased with age and the social structure showed greater cohesion in the 4-year-old class. Gender was an organizing principle in the social structure of the 4-year-old class and became more apparent across time in the 3-ye...

The oncoprotein Ras transforms cells by binding to one or more effector proteins. Effector proteins have been identified by their ability to bind to Ras in the GTP but not GDP form, and by their requirement for the Ras effector domain for binding. The best understood Ras effectors are serine/threonine kinases of the Raf family, but other candidate Ras effectors, including a Ral guanine nucleotide dissociation stimulator and phosphatidylinositol 3-kinase (PI3 kinase) have also been identified. To investigate the mechanism of binding of cRaf-1 to Ras, and to investigate the roles of other candidate Ras effectors in transformation, we have isolated and characterized mutants of activated Ras with decreased binding to cRaf-1 relative to other candidate effectors. Examination of these mutants indicates that surface-exposed residues of Ras outside the minimal effector domain interact differentially with cRaf-1 and other Ras-binding proteins, and that fibroblast transformation correlates with cRaf-1 binding and mitogen-activated protein (MAP) kinase activation. Furthermore, activation of PI3 kinase can occur in the absence of significant MAP kinase activation, suggesting that PI3 kinase activation is a primary effect of Ras.

Human perceptions of the relationship between pollution and food safety are often haphazard and contradictory, based on a variety of sources of information. Recent media events concerning seafood and coastal pollution have generated concern that an otherwise healthy food— fish and shellfish—has become dangerous. We assess consumer knowledge about seafood safety and coastal pollution using several methods, including tests of cultural consensus. We find that consumers view seafood as far more threatened by pollution than scientific analysis suggests, due in part to their perceptions about the dynamics of the marine environment. Finding variation in perceptions within our population based on income and other factors, we explore the use of the cultural consensus approach in large and heterogeneous populations.

Introduction This chapter examines the methods employed in research exploring the relationships between systems of human relations, or social networks, and people’s interactions with various elements of natural ecosystems. Social networks are fundamental to understanding cultural systems of resource sharing; cooperation in hunting, fishing, and agricultural production; the diffusion of technological innovations; the sharing and distribution of ecological and environmental knowl­edge; and in human adaptive responses to changes at various scales from acute ecological disruptions, such as hurricanes, to major environmental shifts, such as global climate change. In addition, human behavioral and ecological networks are interconnected in ways that can foster change through direct and indirect network effects and through system cascades. Thus, factors contributing to changes in ecosystem structure and function at one level (e.g., climate change) can influence the structure of human behavioral systems and, conversely, factors affecting changes in the structure of human behavioral systems (e.g., shifts in fishing effort due to prices or regulation) can ultimately impact elements of ecosystem function (e.g., top-down trophic cascades). Several interesting social network theoretical principles may be at play in the linking of human and natural systems and in understanding and modeling human environmental and ecological behavior. These include such things as homophily (e.g., “birds of a feather flock together”), preferential attachment (e.g., “the rich get richer”), and various topological motifs or features of both ecological and social networks (e.g., small worlds, clustering, transitivity, cohesion). In addition, social capital, a recent social scientific interest, is usually conceptualized in social network terms (Burt 1992; Lin 2002).

Funding support, and the realization by fishery managers that social science research has much to offer in the management process, have combined to create a framework for important research activity in recent years. This paper describes three projects of varying breadth, depth, and scope in which social scientific scholarship has both theoretical and applied value. The first project was a research effort in which funding first allowed for the construction of an appropriate theoretical model and hypotheses, and then supported the research, application, and evaluation. The second project illustrates how available theory and methods can be adapted to the solution of a basic problem in fisheries management, namely how to involve those who are affected by policies and regulations in the formation of those policies and regulations. The third project addresses the issue of conflict of fisheries management and locates marine resource conflicts within a larger conceptual context. This is also an area in w...

Peasant fishers throughout Latin America and the Caribbean typically combine fishing with wage labor to varying degrees. Certain scholars have interpreted this as a reflection of incomplete incorporation into capitalist spheres of influence, where contradictions emerge as groups attempt to maintain economic and cultural autonomy while being subordinated to capitalist relations of production. In this article we investigate the conceptual and political consequences of this process among Puerto Rican fishers. We find that fishers have appropriated the concepts of “class” and “therapy” from their participation in the formal economy and have adapted these concepts to the politics and semantics of artisanal fishing. [fishing, hegemony, semiproletarianization, Puerto Rico]

Ecosystem components interact in complex ways and change over time due to a variety of both internal and external influences (climate change, season cycles, human impacts). Such processes need to be modeled dynamically using appropriate statistical methods for assessing change in network structure. Here we use visualizations and statistical models of network dynamics to understand seasonal changes in the trophic network model described by Baird and Ulanowicz [Baird, D., Ulanowicz, R.E., 1989. Seasonal dynamics of the Chesapeake Bay ecosystem. Ecol. Monogr. 501 (59), 329-364] for the Chesapeake Bay (USA). Visualizations of carbon flow networks were created for each season by using a network graphic analysis tool (NETDRAW). The structural relations of the pelagic and benthic compartments (nodes) in each seasonal network were displayed in a two-dimensional space using spring-embedder analyses with nodes color-coded for habitat associations (benthic or pelagic). The most complex network was summer, when pelagic species such as sea nettles, larval fishes, and carnivorous fishes immigrate into Chesapeake Bay and consume prey largely from the plankton and to some extent the benthos. Winter was the simplest of the seasonal networks, and exhibited the highest ascendency, with fewest nodes present and with most of the flows shifting to the benthic bacteria and sediment POC compartments. This shift in system complexity corresponds with a shift from a pelagic- to benthic-dominated system over the seasonal cycle, suggesting that winter is a mostly closed system, relying on internal cycling rather than external input. Network visualization tools are useful in assessing temporal and spatial changes in food web networks, which can be explored for patterns that can be tested using statistical approaches. A simulation-based continuous-time Markov Chain model called SIENA was used to determine the dynamic structural changes in the trophic network across phases of the annual cycle in a statistical as opposed to a visual assessment. There was a significant decrease in outdegree (prey nodes with reduced link density) and an increase in the number of transitive triples (a triad in which i chooses j and h, and j also chooses h, mostly connected via the non-living detritus nodes in position i), suggesting the Chesapeake Bay is a simpler, but structurally more efficient, ecosystem in the winter than in the summer. As in the visual analysis, this shift in system complexity corresponds with a shift from a pelagic to a more benthic-dominated system from summer to winter. Both the SIENA model and the visualization in NETDRAW support the conclusions of Baird and Ulanowicz [Baird, D., Ulanowicz, R.E., 1989. Seasonal dynamics of the Chesapeake Bay ecosystem. Ecol. Monogr. 501 (59),329-364] that there was an increase in the Chesapeake Bay ecosystem's ascendancy in the winter. We explain such reduced complexity in winter as a system response to lowered temperature and decreased solar energy input, which causes a decline in the production of new carbon, forcing nodes to go extinct; this causes a change in the structure of the system, making it simpler and more efficient than in summer. It appears that the seasonal dynamics of the trophic structure of Chesapeake Bay can be modeled effectively using the SIENA statistical model for network change. (C) 2009 Elsevier B.V. All rights reserved.